Myron L 750 II Series User manual

INSTALLATION • OPERATION • MAINTENANCE
Conductivity/TDS Models: 756II, 757II, 758II & 759II
Resistivity Models: 751II, 752II, 753II & 754II
750 Series II
CONDUCTIVITY/TDS
&
RESISTIVITY
MONITOR/CONTROLLER
Operation
Manual
16 November 17
ACCURACY • RELIABILITY • SIMPLICITY
Water Quality Instrumentation
Accuracy • Reliability • Simplicity
PO# TR179853
Manuf #: 753II-12-PC
0-12M OHM RESISTIVITY METER
Manuf #: CS10
RESISTIVITY SENSOR
Manuf #: CS14
2M OHM CALIB UNIT
REFERENCE #133418
RELAY
INTERNAL CO BATCH 203/2009
RE: ITEM ADDED
INTERNAL CO BATCH 330/2009
RE: ITEM AMENDED FROM EA TO CHG
NEW MODEL #753II-12-SC-PC
RES-DIGITAL MONITOR/CONTROL
AS PER QUOTE #106488 DATED
OCTOBER 28, 2009
INTERNAL CO BATCH 211/2009
RE: ITEM ADDED
INTERNAL CO BATCH 330/2009
RE: ITEM AMENDED FROM EA TO CHG

i

If you read nothing else in this
manual please read this
Quick Reference Guide.
PLEASE READ and COMPREHEND ALL
WARNINGS, CAUTIONS and ADVISEMENTS
CONTAINED WITHIN THIS MANUAL.
Failure to comply is beyond the responsibility of
the Myron L®Company.
WARNING: ALL MONITOR/CONTROLLERS ARE
FACTORY SET TO OPERATE ON 115 VAC. BEFORE
APPLYING POWER ENSURE THE INPUT POWER
“115/230 VAC” SELECTION IS CORRECT FOR YOUR
REQUIREMENTS. FAILURE TO DO SO IS BEYOND
THE RESPONSIBILITY OF THE MYRON L®COMPANY.
See section II.E.2. and gure II.E.1.
NOTE: SOME MODELS MAY HAVE EITHER A 24 VAC
OR A 24 VDC INPUT POWER REQUIREMENT - CHECK
LABELS CAREFULLY.
WARNING: ENSURE POWER IS OFF WHILE
INSTALLING ELECTRICAL EQUIPMENT. IF
MONITOR/CONTROLLER IS INSTALLED, ENSURE
THE POWER IS OFF BEFORE SERVICING. FAILURE
TO DO SO COULD CAUSE DAMAGE TO THE
INSTRUMENT, AND COULD BE HARMFUL OR FATAL
TO PERSONNEL. ONLY QUALIFIED PERSONNEL
SHOULD INSTALL OR SERVICE ELECTRICAL
EQUIPMENT.
WARNING: THE DISPLAY WILL BE IRREPARABLY
DAMAGED IF THE DISPLAY HARNESS IS INSTALLED
UPSIDE-DOWN OR MISALIGNED. THE HARNESS
MUST BE INSTALLED AS SHOWN IN FIGURE II.E.8.
CAUTIONS:
Before installation, ensure you have the correct
model (with options), AND it is ranged for your
application. See sections I.A., I.B. & I.G.
Do you have the correct sensor? See section I.E.
Mounting requirements. What is needed? See
section II.B.
The following will give the installer and user a quick
overview. See the sections listed for details.
REMOVING FRONT PANEL
NOTE: When opening instrument, remove front cover with care;
a ribbon cable connects the front panel and main board.
1. Ensure power is OFF.
2. Remove the four (4) screws on the front panel.
3. Carefully wiggle the front panel to loosen the gasket and
pull gently toward you. Do not pull more than about 8
inches/20CM or you could damage the wiring harness.
REASSEMBLY
1. Carefullyreinstallthefrontpanel,bottomrst.
Ensure no wires have been pinched between
enclosure and front panel.
2. Reinstall the four (4) screws and tighten.
3. To operate, turn power ON.
INTRODUCTION - Section I.
Thissectioncoversthespecicationsofyournew
Monitor/controller including sensor information.
INSTALLATION - Section II.
This section covers how to install your new Monitor/controller;
mechanically and electrically.
OPTIONS & ACCESSORIES - Section III.
Thissectioncoversthespecications,installation,setup,and
operation of each option.
QUICK LOCATOR
SC/SCO MODULE, (Second Relay), see section III.A.
4A/4AO MODULE (4-20mA), see section III.B.
TP/TPO MODULE (Temperature), see section III.C.
TH/THO MODULE (Alarm /control Harness), see section III.D.
DUAL (stacking) Temperature (TPO) & 4-20mA (4A/4AO), see
section III.E.
3SO/3SE MODULE (3 Sensor option) , see section III.F.
3RO/3RE MODULE (3 Range option), see section III.G.
3SRO/3SRE MODULE (Combined 3 Sensor & 3 Range option),
see section III.H.
PA/PAO (Piezo Alarm), see section III.I.
RA (Remote Alarm), see section III.J.
OPERATING PROCEDURES - Section IV.
This section covers a brief description of different models and
their features; how they work, and how to set them up for your
particular use.
QUICK SET POINT CONVERSION (SPC) /
REVERSING SET POINT - See Section IV.C.1.
Conductivity/TDSMonitor/controllersareconguredtotrigger
the alarm relay as the conductivity/TDS reading increases.
ResistivityMonitor/controllersareconguredtotriggerthealarm
relay as the resistivity reading decreases.
To reverse:
1. Locate the jumper block for the alarm to be
  congured.SeegureV.A.1.
2. Remove and rotate the jumpers 1/4 turn and reinstall
them on their posts.
QUICK CHECK-OUT PROCEDURE -
See Section IV.C.2.
It is assumed that the Monitor/controller power is ON, that it is
750 Series II MONITOR/CONTROLLER
QUICK REFERENCE GUIDE
Continued

connected to an appropriate Sensor, and that the Sensor is
immersed in water within the range that the Monitor/controller will
be required to read; and the front panel is removed.
1. Make a note of the reading on the display.
2. While pressing the Calibration/Full Scale Test Switch
(FSSW), verify that the front panel display is indicating
  afullscalereading.Ifnot,seeCalibration,sectionV.C.
3. Press and hold the “SET POINT” switch on the front
panel. Using a tweaker or a small screwdriver, adjust
the Set Point trimmer adjustment screw on the circuit
board to sweep the display from zero to full scale. (A
digital display may be blank at the full scale end. This
is normal.) Listen for the alarm relay to click on and off
as the alarm set point moves past the water reading.
4. Adjust the alarm to the desired set point value. Release
the “SET POINT” switch.
NOTE: For Models with SC/SCO module, repeat STEPS 3 & 4 to
check out Set Point #2.
QUICK SET POINT ADJUSTMENT -
See Section IV.C.3.
Thesetpointsettingisbasedupontheuser’sparticularwater
purityspecicationsorrequirements.NOTE: The optional
secondrelay/alarmis“stacked”ontherstrelay/alarm,
therefore, when setting the optional second relay/alarm Set
Point,the#1SetPointmustbe‘set’rst.
1. While pressing the “SET POINT” switch, turn the Set
  Point#1adjustmentscrew(seegureV.A.1)untilthe
desired set point value is indicated on the display.
HYSTERESIS (DEAD BAND) ADJUSTMENT -
See Section IV.C.4.
PRIMARY COMPONENT IDENTIFICATION -
Section V.A.
ReviewthegurebelowtofamiliarizeyourselfwiththeMain
circuit board assembly. The diagram has the second alarm/
control module option installed.
QUICK CALIBRATION - Section V.C.
WARNING: When performing calibration procedures,
the technician must take extreme care to avoid
contacting the circuitry other than the CALibration
control. Failure to do so could result in damage to
the equipment, property and/or personal injury.
The following assumes the front panel has been
removed and the power is ON.
ELECTRONIC CALIBRATION (CIRCUIT ONLY) -
See Section V.C.1.
Full Scale Adjustment
1. Press and hold the Full Scale Test switch. The display
should indicate Full Scale for the particular range
selected, i.e. 0-500 ppm should indicate 500. If not, set
to Full Scale with the CALibration control.
2. Turn power OFF.
3. Re-install front panel as described in “REASSEMBLY”.
4. To operate, turn power ON.
10VDC Calibration - See Section V.C.1.b.
Using Standard Solutions - Section V.C.2.
The BEST method of verifying and recalibrating your
conductivity/TDS Monitor/controller is with NIST traceable
Standard Solution (available from the Myron L®Company).
Because it includes the sensor, the entire system is recalibrated.
NOTE: Since standard solution calibrations are NOT practicable
withresistivitymodels,anothermeansofvericationor
calibration of resistivity models is to use the transfer standard
method, using a hand-held or portable instrument capable of
resistivity measurements, i.e. the Myron L Ultrameter II™. See
sectionV.C.4fordescription.
The following procedure describes the easiest method for
standard solution calibration of your Conductivity/TDS
Monitor/controller.
1. Using a standard solution which is 60-90% of full scale
 oftheinstrument,rinsethoroughlyandllacleanglass
beaker with the standard solution.
2. Place sensor in the beaker of standard solution. The
level of standard solution must be high enough to cover
at least 1/2” above cross hole.
3. Slowly shake the sensor to remove air bubbles from
inside the sensor bore hole.
4. Allow 5-10 minutes for temperature to equilibrate. For
the quickest and the best results, both the sensor and
solution should be at the same temperature.
5. Turn power ON.
6. If the reading is different from the standard solution,
adjust CALibration control on the main circuit board
until the reading matches the solution value.
7. After adjustment, turn power OFF.
8. Re-install front panel as described in “REASSEMBLY”.
9. To operate, turn power ON.
SENSOR SUBSTITUTE CALIBRATION -
See Section V.C.3.
TRANSFER STANDARD METHOD - See Section V.C.4.
5/21/03
Figure V.A.1
B
L
K
W
H
T
SENSOR
RANGE
MODULE
MAIN
CALIBRATION
CONTROL
SC/SCO
OPTIONAL
SECOND
ALARM/
CONTROL
MODULE
#2 RELAY
LIGHTS &
SWITCH
CONNECTOR
RUBBER TAPE
(DO NOT
REMOVE)
RANGE
MODULE
ALIGNMENT
3SO/3SE
&/OR
3RO/3RE
SWITCH
OR
FLOW SWITCH
CONNECTION
POWER
AC LINE/ +DC
AC NEUTRAL/ -DC
GROUND
RELAY #1
}
COM
NC NO
DISPLAY/METER
CONNECTOR
4-20 CONNECTOR
SET POINT #1
CONVERSION
SET POINT #2 CONTROL
SET POINT #2
CONVERSION
DISPLAY CALIBRATION
CONTROL (FACTORY SET)
SET POINT #1
HYSTERESIS
RIGHT INC
LEFT DEC
CHASSIS GROUND - OEM
SET POINT #2 HYSTERESIS
RIGHT INC / LEFT DEC
SOLID STATE (24VDC 30mW)
OUTPUT
PA™ PIEZO ELECTRIC ALARM
OR
RA™ REMOTE ALARM OR
CUSTOMER CONNECTION
SOLID STATE (24VDC 30mW)
OUTPUT
RA™ REMOTE ALARM AND
PA™ PIEZO ELECTRIC ALARM
OR
CUSTOMER CONNECTION
RELAY #2
}
COM
NO
NC
FULL SCALE
PUSH TO TEST
SET POINT
#1 CONTROL
0-10VDC OUTPUT
N
E
U
(+)
(-)
R
E
D
G
R
N
3S
PA
HYS1SP1FS SW
DIS
INC
DEC
CAL
INC
-121
2000µS
}
SPC
TRANSFORMER
FUSE*
115/
230
751 756
752 757
753 758
754 759
CHS
GND
PWR C GD NC NO CM
CM NO NC
SPC
INC
UP
+
+
PA RA
{
BK WT RD GN NU R- R+
REMOVE TO INSTALL
SECOND RELAY

1
750 Series II
Model 758 -121-SC
(A Digital Conductivity
Monitor/controller,
with a Range of 0-2000 µS,
and a Second Alarm/control,
Displaying Full Scale)
II
HIGH
LOW
SET POINT
MICROSIEMENS / CM
750II

TABLE OF CONTENTS
750 Series II ILLUSTRATION (758II-121-SC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
I. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
A. SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1. Functional Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
B. SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
C. OPTIONAL FEATURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
D. ACCESSORIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
E. SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1. Conductivity/TDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2. Resistivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
    3.  SensorSpecications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
F. ORDER INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1. How to order Monitor/controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2. How to order Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
G. RANGE SELECTION GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
II. INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
A. GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
B. MECHANICAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1. Surface Mounting with SMP (surface mounting plate) Assembly . . . . . . . . . . . . . . . . . . . . . 9
2. Surface Mounting without SMP Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3. Panel Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
C. OEM MECHANICAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
1. Circuit Board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2. Analog Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3. Digital Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
D. SENSOR INSERTION / DIP MOUNT ASSEMBLIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
1. Insertion Mode Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2. Alternate Dip Sensor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
E. ELECTRICAL INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1. Main AC Power Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
    2.  115/230VACConversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
3. Connecting the Sensor Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
      a.  ModicationforUSPharmaceutical25(NoTemperatureCompensation) . . . . . . . . . . .12
4. Solid State Output Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
a. Piezo Electric Alarm Installation (option). . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
b. Remote Alarm Connection (RA option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
c. Connect to your own alarm or ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
5. Alarm/control Relay Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
6. Connecting Display Harness to Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
  F.  0-10VDCOUTPUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
1. Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
    2.  VoltageDivider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
G. RE-RANGE YOUR MONITOR/CONTROLLER (Range Module Installation). . . . . . . . . . . . . . . . . . . .16
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
3. Changing Analog Meter Scale (dial). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
4. Label Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
III. OPTIONS & ACCESSORIES INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
A. SC/SCO MODULE (SECOND ALARM/CONTROL OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . . .19
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
2
SECTION PAGE

TABLE OF CONTENTS Continued
SECTION PAGE
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
a. Set Point Conversion (SPC) / Reversing Set Point . . . . . . . . . . . . . . . . . . . . . . .20
b. Set Point Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
c. Hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
d. Second Relay Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
e. Solid State Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
B. 4A/4AO MODULE (4-20mA OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
3. Recalibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
    4.  ConvertingaCurrenttoaVoltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
C. TP/TPO MODULE (TEMPERATURE OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
3. Recalibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
a. TPC “Calibration” Module Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
b. Precision Resistor Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
c. System Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
4. Alarm/control Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
5. OEM Installation (Single Display) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
6. OEM Installation (Dual Display) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
D. TH/THO MODULE (ALARM /CONTROL HARNESS OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . .34
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
E. DUAL (stacking) TEMPERATURE MODULE (TPO) & 4-20mA MODULE (4AO). . . . . . . . . . . . . . . . . .39
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
F. 3SO/3SE MODULE (3 SENSOR OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
    3.  Alarm/controlConguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
G. 3RO/3RE MODULE (3 RANGE OPTION) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
    3.  Alarm/controlConguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
H. 3SRO/3SRE MODULE (COMBINED 3 SENSOR & 3 RANGE OPTION) . . . . . . . . . . . . . . . . . . . . .45
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
    3.  Alarm/controlConguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
I. PA PIEZO ALARM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
J. RA REMOTE ALARM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
2. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
IV. OPERATING PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
A. FRONT PANEL INDICATORS & CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
1. Red “Set Point” LED Indicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
2. Green “Set Point” LED Indicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
3. “Set Point” Switch(es) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
4. Analog Meter or Digital Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
3

TABLE OF CONTENTS
5. Optional Front Panel Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
B. OEM FRONT PANEL INDICATORS & CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
1. Red “Set Point” LED Indicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
2. Green “Set Point” LED Indicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
3. “Set Point” Switch(es) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
4. Analog Meter or Digital Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
5. Optional Panel Mounted Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
C. SETUP PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
1. Set Point Conversion (SPC) or Reversing Set Point . . . . . . . . . . . . . . . . . . . . . . . . . . .54
2. Check-Out Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
3. Set Point Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
4. Hysteresis (Dead Band) Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
V. COMPONENT IDENTIFICATION, CALIBRATION AND PREVENTIVE CARE . . . . . . . . . . . . . . . . . . . . . . .56
A. PRIMARY COMPONENT IDENTIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
B. METER MECHANICAL ZERO PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
C. CALIBRATION PROCEDURES - MAIN CIRCUIT BOARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
1. Electronic Calibration (Circuit Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
2. Calibration Using Standard Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
3. Sensor Substitute Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
4. Transfer Standard Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
  D.  PREVENTIVECARE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
VI. OPTIONS & ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
A. OPTIONS ORDERED WITH MONITOR/CONTROLLER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
B. OPTIONS & ACCESSORIES ORDERED SEPARATELY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
C. STANDARD SOLUTIONS & BUFFERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
VII. REPLACEMENT PARTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
VIII. WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
IX. GLOSSARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
X. NOTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
XI. ADDENDUM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
  A.  CONDUCTIVITY,TDSANDTEMPERATURERELATIONSHIPS . . . . . . . . . . . . . . . . . . . . . . . . .67
4
SECTION PAGE

Thank you for selecting one of the Myron L®Company’s
750 Series II Monitor/controllers. The 750 Series II is based on
inputfrom‘you’-ourcustomers,timeprovendesigns,andmany
years of instrumentation experience.
Since 1957, the Myron L®Company has been providing
customers with quality products at an affordable price by
designing and producing products that are Accurate, Reliable,
Simple to use. Quality you have come to rely and depend on.
As you read through this operation manual you will see the
750 Series II is truly designed to be user friendly with simple
to install options, and easy re-rangeability as conditions or
applications change. This manual is actually more complex than
the 750 Series II Monitor/controller, but must be to address all
the variables.
Where applicable the Original Equipment Manufacture (OEM)
modelsareseparatedasnecessarytoclarifyanddenetheir
differences.AsdenedbytheMyronL®Company, an OEM
model does not have an enclosure. However, many OEMs use
our enclosure just as if it were a standard model, therefore,
as an end user you must decide whether to follow the OEM
instructions or the “standard” models with enclosure.
All OEMs mount the circuit board assemblies in differing
locations making it impossible for us to describe exactly where
tondthem.BylookinginsectionV.fortheMaincircuitboard
(CB) assembly, you will have a picture of what it looks like. If
your OEM has a display, follow the display harness back to
the Main CB. Once located you will be able to locate installed
options by following the harnesses, i.e. 4A (4-20 mA output).
A. SCOPE
This operation manual provides the user with the necessary
information to install, operate and maintain the Myron L®
Company’s750SeriesII Conductivity/TDS & Resistivity
Monitors/controllers.
SectionI.providesDescriptions,Applications,Specications.
Section II. Installation; mounting, wiring and set up.
Section III. Options and Accessory installation procedures.
SectionIV.Operatingprocedures.
SectionV.Identiestheirprimarycomponentsandprovidesthe
user with easy-to-use calibration and preventive care
procedures.
SectionVI.Options&AccessoriesList.
SectionVII.ReplacementComponents.
SectionVIII.Warrantyinformation.
SectionIX.Glossary,denitions.
Section X. Notes.
Section XI. Addendum.
1. FUNCTIONAL DESCRIPTIONS
All models except OEMs have water & corrosion resistant IP64/
NEMA 3 housings suitable for panel, bench or surface mounting.
The 750 Series II are a compact 6.0” (152mm) x 4.8” (122mm).
Bright green/red LEDs indicate HIGH/LOW set point readings.
All models except 751II, 754II, 756II, & 759II, (see below)
feature a heavy-duty 10 amp output relay, operating on either
increasing or decreasing readings.
ForspecicMonitor/controllercongurations,referencethe
following individual model descriptions.
Models 757II Conductivity/TDS & 752II Resistivity
Analog Monitor/controller. Standard front panel is equipped
with a linear analog meter display and a “SET POINT” switch
with High/Low indicator lights. Single set point is internal to
discourage unauthorized adjustments. A second set point
alarm/control is available as an option. 4-20mA output option is
available on OEM models only.
Models 758II Conductivity/TDS & 753II Resistivity
Digital Monitor/controller. Standard front panel is equipped with
a 3 1/2 digit liquid crystal display (LCD), and a “SET POINT”
switch with High/Low LED indicator lights. Single set point is
internal to discourage unauthorized adjustments. A second
set point alarm/control is available as an option. May use an
optional 4-20mA output for PLC or SCADA operations.
Models 756II Conductivity/TDS & 751II Resistivity
Analog monitor ONLY. Standard front panel is equipped with a
linear analog meter, no relay, LED indicators or set point switch.
A 4-20mA output option is available on OEM models only.
Models 759II Conductivity/TDS & 754II Resistivity
Digital monitor ONLY. Standard front panel is equipped with a
3 1/2 digit liquid crystal display (LCD) only, no relay, LED
indicators or set point switch. May use an optional 4-20mA
output for PLC or SCADA operations.
2. APPLICATIONS
Conductivity/TDS
Reverse Osmosis
Process Control
Seawater Desalinization
Wastewater Treatment
Food Processing
Plating
Power Plants
Laboratories
Printing
Boiler
Cooling Tower
Agriculture/Aquaculture
Are just a few of the applications
Resistivity
Deionization (DI) and Distillation Ultrapure Water
Treatment Systems
Electronics
Pharmaceutical
Laboratories
Food Processing
Plating
Power Plants
Are just a few of the applications
B. SPECIFICATIONS
RANGES: 34 Conductivity/TDS ranges from
0-1µS/µM/ppm to 0-200mS/mM/ppt
   7Resistivityrangesfrom0-200KΩto0-20MΩ.
Refer to Range Selection Guide on Page 8.
DISPLAY:
Models 756II, 757II & 751II, 752II:
2 1/2” (63mm) analog meter
Models 758II, 759II & 753II, 754II:
13mm/ 1/2” 3 1/2 digit LCD
5
I. INTRODUCTION

NOTE: 3 1/2 digit LCD may be replaced with either a 3 1/2 or a
4 1/2 digit backlit LCD - available as options.
ACCURACY
Analog Models: + 2% of Full Scale
Digital Models: + 1 % of Full Scale
SENSITIVITY
0.05% of span
STABILITY
0.05% of span
REPEATABILITY
0.1% of span
CALIBRATION CHECK
Built in full scale value
RECORDER OUTPUT
0-10VDC@5mAmax.(linear);standardonallmodels
OUTPUT IMPEDANCE
 100Ω±5%
SENSOR INPUT 1 (optional 3 sensor input available)
CONTROL FUNCTION
Models 757II, 758II & 752II, 753II:
Single set point alarm/control continuously adjustable
0-100% of span
Second set point alarm/control (Optional).
Continuously adjustable - 0-100% of span
Hysteresis
Adjustable from 0.3-3% of full scale
Indicators
“HIGH” (red) and “LOW” (green) set point LEDs - reversible.
Relay Contact Rating
SPDT10amp@250VAC,30VDC.Relayoperates
increasing or decreasing reading (user selectable).
Solid State Output
24VDCunregulated,30mAMaximum.
Powers optional PA - Piezo Electric Alarm, RA™ - Remote
Alarm, or ?
SecondAlarm/controlModule,withabovespecications,opt.on
Models 757II, 758II & 752II, 753II
POWER SPECIFICATIONS
115/230 VAC±15%,50/60Hz(Userselectable)
overvoltage category II
100 mA Maximum Current
Double Insulated (with circuit board ground for OEM
operation)
Fuse-100mASlowBlow(T.10A)forboth115&230VAC
  (V~)Userreplaceable
Humidity - 20-90% non-condensing
Max. Altitude -
12,000 meters/40,000 ft non-operating
3000 meters/10,000 ft operating
Pollution degree 2
24 VAC or 24 VDC Option available on Special Order
OvervoltagecategoryII(24VAC)
250 mA Maximum Current
Double Insulated (with circuit board ground for OEM
operation)
Fuse - 250mA Slow Blow (T.25A) User replaceable
AMBIENT TEMPERATURE RANGE
0-60ºC/32-140ºF
DIMENSIONS
152H x 122W x 96 D mm / 6.0 H x 4.8 W x 3.8 D in.
HOUSING CONSTRUCTION
Fully gasketed heavy-duty ABS for splash-proof and corrosion
resistance.
Rated IP65/NEMA 4X
Double Insulated (with circuit board ground for OEM operation)
WEIGHT
750 Series II: average 0.9 kg/2 Ibs.
C. OPTIONAL FEATURES
SeesectionsVI&VIIforcompleteselectionanddetails.
-SC Second Alarm/control Module (M/c only)
-4A 4-20 mA Isolated output (digital models only)
-PA 70 db Piezo Electric Alarm (digital M/c only)
-PAT Piezo Alarm & Timer Module (digital M/c only)
-45BL 4 1/2 Digit Backlit Liquid Crystal Display (LCD)
-35BL 3 1/2 Digit Backlit Liquid Crystal Display (LCD)
-TP Temperature Module 0-200ºC, requires -TP sensor
(digital Monitor/controllers only)
-TH Alarm/control Interface Harness (req. SC & TP)
(digital only)
-PC  115VACPowercord(8ft./2,44meters)withUSA
plug and strain relief - NOTforusewith230VAC.
-24VA 24VACIsolatedPowerSupply(specialorder)
-24VD 24VDCIsolatedPowerSupply(specialorder)
-PTS Panel mounted Full Scale Test switch (special order)
D. ACCESSORIES (ordered separately)
  SeesectionsVI&VIIforcompleteselectionanddetails.
ASI AQUASWITCH I, auto RO/DI switching system (req. M/c)
SCO Second Alarm/control Module (Monitor/controllers only)
4AO 4-20 mA Self-Powered Isolated Output Module
(digital only)
3SE 3 Sensor Input Module with Enclosure.
3SO 3 Sensor Input Module with 1 meter/3 foot cable*.
3RE 3 Range Switch with Enclosure†
3RO 3 Range Switch with 1 meter/3 foot cable†*.
3SRO Above 3SO & 3RO combined with enclosure†.
3SRE Above 3SO & 3RO combined†*.
PAO 70 db Piezo Electric Alarm only (753II/758II)
PATO Piezo Alarm & Timer Module (753II/758II)
45BLO 4 1/2 Digit Backlit Liquid Crystal Display (LCD)
35BLO 3 1/2 Digit Backlit Liquid Crystal Display (LCD)
TPO Temperature Module 0-200ºC - requires -TP
sensor (digital models only)
THO TP/TPO Alarm/control Harness only
(requires SCO & TPO)
PCO  PowerCord115VAC(8ft./2,44meters)withUSA
plug and strain relief - NOTforusewith230VAC.
SMP50 Surface Mounting Plate
RA Remote Alarm™ - RA (Monitor/controllers only)
VR  PowerSupply,24VAC,20VA.(115VAC,indooruse)
024-1  1in.NPT24VACSolenoidValve
CS-11 20ΩResistivityCalibrationModule(NISTTraceable)
CS-14 2ΩResistivityCalibrationModule(NISTTraceable)
CS-17 200ΩResistivityCalibrationModule(NISTTraceable)
†Add Cfor Conductivity or Rfor Resistivity to part number
*Customer mounted separately
6
DOUBLE INSULATED

E. SENSORS
1. CONDUCTIVITY/ TDS
750 Series II Conductivity/TDS Monitor/controllers use the
CS51LC, CS51 or CS52 Series sensor depending on range.
The 1.0 cell constant CS51 model is recommended for ranges
of 0-10 through 20,000 µS/ppm. Its compact size allows
mounting in a standard 3/4” tee. The sturdy polypropylene
bushing is modular for easy, inexpensive replacement. Other
models available by special order.
CS52 sensors have a 10.0 cell constant and are used for
conductivity/TDS values above 20,000 µS/ppm.
CS51LC sensor has a cell constant of 0.1 and is used for
conductivity/TDS values of 0-1 to 0-5 µS/ppm.
Special order High Temperature, High Pressure sensors;
and Low Cost, Low Temperature, Low Pressure sensors are
available. For detailed descriptions of these and other sensors,
seeSensorSelectionGuideandspecicsensordatasheets
available from your local distributor, the Myron L®Company, or
on line at www.myronl.com.
2. RESISTIVITY
750 Series II Resistivity Monitor/controllers use the CS10
sensor. It has a cell constant of 0.05 and is used for ultra pure
water applications. Other models available by special order.
3. SENSOR SPECIFICATIONS
See sensors price list for complete selection and details.
STANDARD MODELS — 316 Stainless Steel CONSTANT
CS51LC: For ranges 0-5 µS/ppm & below 0.1
CS51: For ranges between 0-10 & 0- 20,000 µS/ppm 1 . 0
CS52: For ranges above 20,000 µS/ppm 10.0
CS10: For ALL Resistivity ranges 0.05
See Range Selection Guide, Page 8.
SPECIAL ORDER MODELS — 316 Stainless Steel
CS40  Conductivity/TDSValveInsertable100psi@120°C
(10.0, 1.0, 0.1 & 0.05)
CS40HT Above High Temp Model
(Temporarily unavailable; contact manufacturer)
CS41  Cond/TDSHighTempModel100psi@150°C
CS41HT Cond/TDSHighTempModel250psi@205°C
CS50  Conductivity/TDS100psi@95°C(1.0&0.1)
CSA Low Cost Conductivity/TDS - NO Temperature
    Compensation75psi@60°C(1.0)
CSATC Low Cost Conductivity/TDS - with Temperature
    Compensation75psi@60°C(1.0)
4. SENSOR OPTIONS
-T Titanium - in place of Stainless Steel
  -TP TemperatureSensor0-200°C(specialorder)
  -WTV Wet-TapValveforCS40(0.1&1.0only)
-JB Junction Box - Class I, Group D, Div. S,
explosion and weather proof aluminum.
For CS40/CS40HT.
-STF Sanitec Fitting for CS10, CS51 & CS51LC.
1/2” thru 4”. State size, i.e. STF1/2.
  -25  25’ShieldedCable(Standard5wiresensor)*
  -100 100’ShieldedCable(Standard5wiresensor)*
  -PV 1/2”PVDFttingforCS10&CS51ONLY
(replaces polypropylene)
  -HPSS 1/2”316STAINLESSSTEELtting
for CS10 & CS51 ONLY (replaces
polypropylene).
* -TP Sensor 8 wire cable, contact the Myron L®Company
TEMPERATURE COMPENSATION
  Automaticto25°C,between0-100°C/32-212°F
  excepthightemperaturemodels-upto205°C.
PRESSURE/TEMPERATURE LIMITS
  CS10&CS51-689.6kPa/100psiat100°C/212°F
  Forhigherlimits,seespecicationsbelow.
BUSHING
CS51 (LC): Modular Polypropylene threaded 3/4” NPT
CS52: 316 stainless steel 3/4” NPT internal to cell body
CS10: Modular Polypropylene threaded 3/4” NPT
CABLE
Shielded; 10ft./3 meters standard
25ft./7 meters and 100ft./30 meters lengths also
available
DIMENSIONS
CS51(LC): Metal portion 30mm/1.2 in. L;
13mm/0.5 in. DIA
CS10: Metal portion 30mm/1.2 in. L; 13mm/0.5 in. DIA
Forothermodelsseesensorselection&specicdatasheetsfor
details.
F. ORDERING INFORMATION
1. HOW TO ORDER MONITOR/CONTROLLERS
EXAMPLE:
MODEL RANGE OPTIONS
758II — 121 — SC - 4A - PA
Written as — 758II-121-SC-4A-PA
This is a Digital Monitor/controller with a 0-2000 µS range, a
Second Alarm/control, a 4-20 mA output and a Piezo Electric
Alarm.
NOTE: Monitor model number does not include sensor. Please
specify sensor required when ordering.
RANGE SUFFIXES:
See RANGE SELECTION GUIDE, Page 8.
2. HOW TO ORDER SENSORS
Add option to model number as in examples below.
EXAMPLE:
MODEL OPTIONS
CS51 — T-TP-100
Written as — CS51-T-TP-100
The above is a model CS51 sensor made with Titanium, with the
Temperature sensor, and a 100 foot cable.
EXAMPLE:
MODEL OPTIONS
 CS41HT— 01-T-WTV-TP
Writtenas — CS41-01-T-WTV-TP
The above is a Special Order High Temperature sensor with a
cellconstantof0.1,madeofTitanium,aWet-TapValveanda
Temperature sensor.
7

RANGE
Resistivity
0-20MΩ
0-10MΩ†
0-5MΩ†
0-2MΩ
0-1MΩ†
0-500KΩ†
0-200KΩ
Conductivity
0-1 µS*†
0-1 ppm*†
0-2 µS*†
0-2 ppm*†
0-5 µS*†
0-5 ppm*†
0-10 µS†
0-10 ppm†
0-20 µS
0-20 ppm
0-50 µS
0-50 ppm
0-100 µS
0-100 ppm
0-200 µS
0-200 ppm
0-500 µS
0-500 ppm
0-1000 µS
0-1000 ppm
0-2000 µS
0-2000 ppm
0-5000 µS††
0-5000 ppm††
0-10,000 µS/0-10 mS††
0-10,000 ppm/0-10 ppt††
0-20,000 µS/0-20 mS††
0-20,000 ppm/0-20 ppt††
0-50,000 µS/0-50 mS**††
0-50,000 ppm/0-50 ppm**††
0-100 mS**††
0-100 ppt**††
0-200 mS**††
0-200 ppt**††
756II, 757II, 758II & 759II
CONDUCTIVITY/TDS
Dash #
-101
-102
-103
-104
-105
-106
-107
-108
-109
-110
-111
-112
-113
-114
-115
-116
-117
-118
-119
-120
-121
-122
-123
-124
-125
-126
-127
-128
-129
-130
-131
-132
-133
-134
751II, 752II, 753II & 754II
RESISTIVITY
Dash #
-11
-12
-13
-14
-15
-16
-17
Add Range NUMBER below to instrument model number, i.e. 758II-”112” = 0-50 ppm Digital Monitor/controller.
G. 750 SERIES II RANGE SELECTION GUIDE
CONDUCTIVITY/TDS & RESISTIVITY
*CS51LC conductivity sensor (0. 1 constant) required for these ranges.
**CS52 conductivity sensor (10.0 constant) required for these ranges.
† Available in Digital models only.
†† Available with 4 1/2 Digit Backlit LCD. Other ranges available as OEM ONLY. Price & delivery on request.
Except as noted, Conductivity/TDS Monitor/controllers require a sensor with a cell constant of 1.0. The Model CS51 is the most
commonly selected sensor due to its ease of use and low cost.
Resistivity Monitor/controllers require a sensor with a cell constant of 0.05. The Model CS10 is the most common selected due to its
ease of use and low cost.
NOTE:UNLESSppm/NaClisspeciedwithorder,TDS/ppmtypeconductivityinstrumentswillbecalibratedtotheMyronL“442™”
Natural Water standard. For NaCl ppm/ppt add the letter “N” after the number, i.e. -124N.
8

A. GENERAL
This section provides the recommended procedures for properly
installing the 750 Series II Conductivity/Resistivity Monitor/
controller, and sensors. For OEM models see section C.
WARNING: THE MYRON L®COMPANY RECOMMENDS THAT
ALL MOUNTING AND ELECTRICAL INSTALLATIONS BE
PERFORMED BY QUALIFIED PERSONNEL ONLY. FAILURE
TO DO SO COULD CAUSE DAMAGE TO INSTRUMENT, AND
COULD BE HARMFUL OR FATAL TO PERSONNEL.
B. MECHANICAL INSTALLATION
All Monitor electronics are packaged inside drip/weather-proof
housings. The physical dimensions of the housing is suitable for
panel, bench or surface mounting.
There are four basic guidelines to consider when selecting a
Monitor’smountinglocation:
1. SelectasitethatlimitstheMonitor’sexposureto
excessive moisture and corrosive fumes.
2. For best results, position your Monitor/controller and
sensor as close as possible to the point(s) being
controlled. The 750 Series II Conductivity/TDS &
Resistivity Monitor/controllers are not designed to
operate with a Sensor cable length that exceeds 100 ft./
30 meters.
3. If at all possible, mount the Monitor at eye level for
viewing convenience.
4. If needed, the enclosure may be rotated or mounted
upside down so that the cutouts are on the opposite
side.
1. SURFACE MOUNTING WITH SMP
NOTE: A Surface Mounting Plate (SMP50) may be required
when access to the back side of the mounting site is impractical
or if the Monitor/controller must be mounted on a solid wall. The
SMP50 comes with the proper hardware to mount the Monitor/
controller to the SMP, however, the installer must provide the
four (4) additional screws/bolts to mount the SMP to the wall or
xture.Theirsizeistobedeterminedbytheuser.
1. Select your mounting location. Mark and drill the four
(4) required mounting holes. For hole locations, use the
SMP as a template.
2. Drill the corner holes in the SMP according to the size
of the screws or bolts selected.
3. Attach and securely fasten the SMP to the Monitor
using the 1/4” X 20 X 3/8” screws provided.
4. Mount the SMP to the prepared site using the selected
screws or bolts.
2. SURFACE MOUNTING WITHOUT SMP
NOTE: Surface mounting will require two (2) 1/4 “ X 20 screws
of a length equal to the thickness of the mounting site plus 3/8”
1. Select mounting site location. Mark and drill the
required mounting holes. For hole drilling locations, see
 gureII.B.1.
2. Insert the 1/4” X 20 screws into the holes from the side
opposite the mounting site.
3. Hold the Monitor in place while starting and tightening
the mounting screws.
3. PANEL MOUNTING
A panel mounting fastening kit is provided with all Monitor/
controllers. Panel mounting will require the use of the fastening
kit’stwo(2)4-40mountingscrews/nutsortwo(2)#4x1/2”
sheetmetalscrews.SeegureII.B.1.forpanelcutout
dimensions.
1. Select your mounting location. Mark the appropriate
panel cutout and complete the necessary panel cut.
2. CarefullyunfastenandseparatetheMonitor’sfront 
panel from its enclosure.
3. Disconnectallpanelcable(s)/wire(s)fromtheMonitor’s
Control board.
NOT TO SCALE
DIMENSIONS IN INCHES
(MILLIMETERS)
3.10
(79)
0.40
(10)
SURFACE
MOUNT
1.05
(27)
2.84
(72)
0.31 DIA, X2
(8)
5.00
(127)
3.96
(101)
0.13 RAD MAX, X
(3)
4
0.113
(3)
2.54
(64)
4.17
(106)
0.11
(3)
PANEL
CUTOUT
HIGHLOW
SET POINT
4.80
(122)
3.89
(99)
(16)
6.00
(152)
0.5
(13)
0.88 DIA
(22)
1.13 DIA
(29)
0.53
(14)
4.94
(126)
0.60 DIA
(15)
3.78
(96)
0.50 DIA
(13)
750
MICROSIEMENS / CM
II
6-32x3/8" x4
Face Plate Gasket
Face Plate Gasket
Panel Gasket
Panel Gasket
0.63 THK
II. INSTALLATION
9
SURFACE AND PANEL MOUNTING DIAGRAMS
Figure II.B.1
!
CAUTION - READ FOLLOWING CAREFULLY
DOUBLE INSULATED

4. Slide the enclosure through the panel cutout
  untilitsangecontactsthepanel.
 5. Insertmountingscrewsthroughtheange
mounting holes and tightly secure.
6. Reconnect all panel cable(s)/wire(s) and re-
secure the front panel using 6-32 x 3/8”
screws provided.
Caution: Do not use 6-32 x 1/2” used on “picture
frame” front panel models.
C. OEM MECHANICAL INSTALLATION
This section provides the recommended procedures for properly
installing the OEM 750 Series II Conductivity/Resistivity Monitor/
controller.
NOTE: Mounting of the OEM monitor/controller circuit board
is left up to the OEM. It is recommended that the following be
noted and observed.
1. CIRCUIT BOARD
Total height of CB is 1.40” (36mm).
The circuit board has four (4) .175” (4.4 mm) holes for mount-
ing. The centers are 3.10” (78.7 mm) x 4.10” (104.1 mm) see
gureII.C.1.CBmustbemountedonatleast.250”(6.35mm)
standoffs to prevent shorting to metal chassis (standoffs user
supplied). CB must be mounted in a clean and dry environment.
Allow working room for inserting wires, testing and calibration.
Indicator lights and switches require 1/4” (6.35mm) holes.
2. METER MOVEMENT
 RefertogureII.C.2fordimensions.
1. Cut opening in user panel.
2. Drill four (4) holes at locations as shown.
3. Install meter movement using supplied
hardware.
4.585
(116.5)
3.600
(91.44)
4.100
(104.1)
3.100
(78.74)
Figure 11.C.1
10
2.218 Dia.
.940
1.880
.940
.125 X4
.940
(23.88)(23.88)
(23.88)
(3.125)
56.34
(47.75)
Analog Meter Hole Pattern
Figure II.C.2
2.390
(60.71)
.980
(24.89)
DIGITAL DISPLAY CUTOUT
PATTERN
Figure II.C.3
3. DIGITAL DISPLAY
RefertogureII.C.3fordimensions.
1. Cut opening in user panel
2. Install LCD with brackets
supplied.

D. SENSOR INSERTION/IMMERSION MOUNTING
TheSensor’smountingorientationmustprovideacontinuous
andadequatecirculationowtopreventthetrappingofair
bubbleswithintheSensor’selectrodearea(CS51shownin
gureII.D.1).Failuretodosowillresultinconditionsthatwill
prevent the Sensor from functioning properly.
1. INSERTION MODE (in-line installation)
Use approved sealant, i.e. Teon tape as required.
 1. VerifythattheSensor’sFittingassemblyisproperly
  assembledasshowningureII.D.1.
 2. InserttheSensorFittingassemblyintothe“T”tting
  withelectrodealignedasshowningureII.D.1.and
tightly secure.
2. IMMERSION OR DIP SENSOR ASSEMBLY
Use approved sealant, i.e. Teon tape as required.
 1. VerifythattheSensor’sFittingassemblyisproperly
  assembledasshowningureII.D.2.
 2. InsertandpulltheSensor’scablethroughthe 
extension tube and then tightly attach extension tube to
  SensorassemblyasshowningureII.D.2.
E. ELECTRICAL INSTALLATION
The electrical installation procedures provided in this manual are
common to all Conductivity & Resistivity Monitor/controllers. See
gureII.B.1.fortheholedimensionsoftheenclosure’scable
accessholes.Unlessotherwiseinstructed,refertogureII.E.1.
for the 750 Series IIMonitor’sterminalblockconnectorwiring
designations.
NOTE:Afterremovinganenclosure’saccessholecutout,itis
suggestedthattheusermountawatertightrestraintxtureprior
to installing a cable.
A device to disconnect the Model 750II from the power
supply is required. It is recommended that this switch or
circuit breaker be labeled as the disconnection device for
the Model 750II.
1. MAIN INPUT POWER INSTALLATION
WARNING: All AC line powered Monitor/controllers are
factory set for 115 VAC. Before starting, ensure the input
power “115/230” selection is correct for your requirements.
Failure to do so is beyond the responsibility of the Myron L®
Company. See section II.E.2. below and gure II.E.1.
NOTE: Some models may have either a 24 VAC or a 24 VDC
input power requirement - check labels carefully.
For OEM models skip to step #7.
 1. VerifythatthemainACpowersourceisturned“OFF”
or disconnected.
2. Using a standard slot screwdriver remove the four (4)
screws on the front panel.
3. Carefully wiggle the front panel to loosen and pull
gently toward you. Do not pull more than about
8 inches/20CM or you could damage the wiring
harness.
INSERTION MODE ASSEMBLY
Figure II.D.1
IMMERSION OR DIP SENSOR ASSEMBLY
Figure II.D.2
ELECTRICAL CONNECT DIAGRAM
Figure II.E.1
SECURING NUT SS
WASHER
PLASTIC
WASHER
O-RING
THREADED FITTING
3/4" FNPT
"T" FITTING
CABLE
OUT
IN
FLANGE
EXTENSION TUBE
CABLE
COUPLING
3/4" NPT
SENSOR TIP
THREADED FITTING
3/4" FNPT
FLANGE
O-RING
PLASTIC
WASHER
SECURING NUT
FUSE
MAIN
INPUT
POWER
GND-GRN
NEU-WHT/-DC
LINE-BLK/+DC
115/230
SWITCH
{
}
{
}
CHASSIS GROUND
FOR
OEM INSTALLATIONS
ONLY
SENSOR
L N
0-10VDC
OUTPUT
NEU
GRN
RED
WHT
BLK
(+)
(-)
ALARM
CONTROL
RELAY
COM
NO
NC
11
!
WARNING!

4. Turn the front panel around so that the back side is
facing you and set aside for now.
5. Carefully remove front panel, leaving the harness
connected.
6. Using the enclosure cutouts, install the proper wire and
watertight cable restraint (not provided) to comply with
local electrical codes.
7. Neatly connect wires to the Main Circuit Board
  connectors,asshowningureII.E.1.
*CAUTION: The input power connectors require only a small
screwdriver or a pen to push on the release levers. The release
levers may be broken or damaged if not pushed straight toward
the circuit board. DO NOT push the release levers sideways.
2. 115/230 VAC CONVERSION
1. Before turning power on to the Monitor/controller
ensure the proper input voltage has been selected.
Failure to do so will blow the fuse. It could, under some
conditions, cause injury and damage the instrument
voiding the warranty.
2. Locate switch located next to the fuse holder.
3. Using a screwdriver, turn switch to required voltage.
3. CONNECTING THE SENSOR CABLE
For OEM models skip #1.
 1. PlacetheSensor’sinterfacecableandusersupplied
  watertightcablerestraintintotheenclosure’s
appropriate access hole.
2. Install the sensor cable wire to comply with local
electrical codes. Follow the color code as marked.
  SeegureII.E.1.
*CAUTION: The sensor connectors require only a small
screwdriver or a pen to push on the release levers. The release
levers may be broken or damaged if not pushed straight toward
the circuit board. DO NOT push the release levers sideways.
a. MODIFICATION FOR US PHARMACEUTICAL
25 (No Temperature Compensation)
ThissimplemodicationwillallowyourMonitor/controller
to meet the USP 25 requirements by defeating the normal
temperature compensation circuit thus giving “uncompensated”
readings as required.
Specications:
As required to meet USP25.
Installation
Briey-
For Conductivity/TDS, a resistor is installed in place of the
sensor “temperature” sensing leads.
For Resistivity, two resistors are installed in place of the sensor
“temperature” sensing leads.
The extra sensor leads are either cut off or the ends are
wrapped in tape to prevent shorting.
WARNING: BEFORE STARTING, IF MONITOR/
CONTROLLER IS INSTALLED, ENSURE THE POWER IS
OFF. FAILURE TO DO SO COULD CAUSE DAMAGE TO
THE INSTRUMENT, AND COULD BE HARMFUL OR FATAL
TO PERSONNEL. ONLY QUALIFIED PERSONNEL SHOULD
INSTALL OR SERVICE ELECTRICAL EQUIPMENT.
Requirements:
ForConductivity/TDS;one10kΩ1%resistor,usersuppliedor
may be ordered from the Myron L®Company.
ForResistivity;one100kΩ1%resistor,andone5.49kΩ
1% resistor, user supplied or may be ordered from the
Myron L®Company.
NOTE: When opening instrument, remove front cover with care;
a ribbon cable connects the front panel and main board. If the
front panel has all ready been removed from the enclosure skip
to #4.
1. Using a standard slot screwdriver remove the four (4)
screws on the front panel.
2. Carefully wiggle the front panel to loosen and pull
gently toward you. Do not pull more than about 8
inches/20CM or you could damage the wiring harness.
3. Turn the front panel around so that the back side is
facing you and set aside.
4. For Conductivity/TDS Monitor/controllers;
a. If sensor is installed, locate and remove the RED
(RD) and the GREEN (GN) leads from MAIN
   CircuitBoard,asshowningureII.E.2.
b. Cut off or tape RED (RD) and the GREEN (GN)
leads from sensor.
  c. Install10kΩresistoratRED(RD)andtheGREEN
   (GN)connectorlocations,asshowningure 
II.E.3.
For Resistivity Monitor/controllers;
a. If sensor is installed, locate and remove the
GREEN (GN), RED (RD), and the NEUTRAL (NU)
   leadsfromMAINCircuitBoard,asshowningure
II.E.4.
b. Cut off or tape GREEN (GN), RED (RD), and the
NEUTRAL (NU) leads from sensor.
  c. Install100kΩresistoratBLACK(BK)andGREEN
   (GN)connectorlocations,asshowningure 
II.E.5.
12
Conductivity/TDS Main CB Assembly
Figure II.E.2
-121
2000µS
UP
}
HYS1SP1FS SW
BK WT RD GN NU R- R+
DIS
CAL
3S
FULL SCALE
PUSH TO TEST
INC
DEC
SPC
0-10VDC
OUTPUT
SENSOR LEADS REMOVE THESE TWO LEADS
!
CAUTION - READ FOLLOWING CAREFULLY

  d. Install5.49kΩresistoratRED(RD)andthe
NEUTRAL (NU) connector locations, as shown in
   gureII.E.5.
 5. Carefullyreinstallthefrontpanel,bottomrst.Ensure
no wires have been pinched between enclosure and
front panel.
6. Reinstall the four (4) screws and tighten.
7. To operate, turn power ON.
NOTE: Recalibration will require both the solution and sensor
  beat25°Cformaximumaccuracy.
4. SOLID STATE OUTPUT
24VDCUnregulated30mAmax.Thefollowinginstructionsare
assuming the Monitor/controller enclosure is already open.
a. Piezo Electric Alarm - PA/PAO (option)
For additional information, see Piezo Alarm under Options in
section III.I.
1. If not already installed, peel tape backing from PIEZO
  andpressintoplacepergureIII.I.3.
2. Attach connector to main control circuit board per
  gureIII.I.4.
NOTE: If remotely mounted; cut wires and splice as necessary,
use comparable wire. Piezo requires 1/4” (6.35mm) hole in user
panel.
b. Remote Alarm - RA™ (option)
For additional information, see RA Instructions under options in
section III.J.
1. Run user supplied #22, 2 conductor speaker type wire
from Monitor/controller to RA location as necessary.
Additional wire may be ordered, part #RAW-200, see
Options & Accessories.
2. Open the RA by removing the four (4) screws.
3. Locate and remove the 8” 2 conductor wire attached
to RA.
4. At the controller, connect the extension wires to the 8”
2 conductor wire with the wire nuts provided — Black
to Positive (+) and White to Negative (-). Be sure to
  rstpassthewirethroughtheusersuppliedwaterproof
strain relief in the enclosure.
5. Plug the reddish brown female connector into the
male connector on the controller CB marked either RA
or PA (see inside case label for location). It will only go
on the connector one way.
6. At the RA, connect the wires to the connector — Black
to Positive (+) and White to Negative (-).
7. To test, simply turn on the controller and adjust
controller set point until the alarm/piezo sounds off. If
controller is not yet connected to a functioning sensor,
on conductivity/TDS controllers it will be necessary to
press and hold the Full Scale test switch.
The black button on the front of the RA will mute the
piezo alarm for approximately three minutes or until
you improve the water quality (readjust controller set
point). The piezo alarm will continue to sound off every
three minutes until the user has improved the alarm
condition inside the controller. If three minutes muting
  isneforyourapplication,skiptostep9.
8. If three minutes is too long or too short, adjust time
delay control inside RA until desired mute time is achieved
(adjustable from approximately 6 seconds to
10 minutes).
9. Replace the bottom of the RA, and secure RA to the
surface you have selected for its installation.
NOTE: If the RA does not sound off;
1. Check the polarity of the extension wire connections.
2. Be sure the controller is actually switching (relay will
click).
13
BK WT RD GN NU R- R+
FS SW
3S
SENSOR LEADS
INSTALL 10KΩ
RESISTOR HERE
CAL
REMOVE THESE
THREE LEADS
FS SW
BK WT RD GN NU R- R+
3S
SENSOR LEADS
CAL
SENSOR LEADS
FS SW
3S
CAL
INSTALL 100KΩ
RESISTOR HERE
INSTALL 5.49KΩ
RESISTOR HERE
BK WT RD GN NU R- R+
Conductivity/TDS Main CB Assembly
Figure II.E.3
Resistivity Main CB Assembly
Figure II.E.4
Resistivity Main CB Assembly
Figure II.E.5

14
c. Connect to your own alarm or ?
Use the following as guidelines.
Connector is a standard 2 wire Methode* style
connector. Connector with 8” wires, part #RAH, is
available from the Myron L®Company.
  Ensureyourrequirementsdonotexceedthe24VDC
Unregulated 30mA maximum.
Ensure the polarity is correct (RED is positive), see
   gureV.A.1.
Attach wires to RA.
  Attachconnectortocontrollerconnector(RA)pergure
  V.A.1.
*Methode is registered trademark of Methode Electronics, Inc.
5. ALARM/CONTROL RELAY CONNECTIONS
Myron L®Company Monitor/controllers are equipped with a
“Dry Contact” relay which is designed to energize/de-energize
whenthesetpointiscrossed.(SeesectionIV.C.3forsetpoint
adjustment procedure) The relay energizes on increasing or
decreasingreadingsassetbytheuser,seesectionIV.C.1.
When energized (above set point), the Common (COM) will
disconnect from the Normally Closed (NC) contact and connect
to the Normally Open (NO) contact. Devices may be operated
using either the Normally Open contact or Normally Closed
contact; or both relay contacts may be used to control two
devices of the same voltage.
NOTE:Aowswitchmaybeinstalled(electricallyconnected)
utilizing one of two convenient methods; the 3S connection, see
gureII.E.2,(removejumperandconnectowswitchacross
terminals - 8” harness (RAH) available from the
Myron L®Company), or in-line with either relay connection,
seegureII.E.6orII.E.7.
WARNING: CONNECTING BOTH POWER SOURCE
LEADS TO THE RELAY TERMINAL BLOCK CONNECTORS
WILL DAMAGE THE CIRCUIT BOARD AND MAY CAUSE
PERSONAL INJURY.
1. Place the user supplied Alarm relay interface cable and
  watertightcablerestraintintotheenclosure’s
appropriate access hole. Skip for OEM.
2. Neatly connect the relay interface cable wires to the
  Monitor/controller’sterminalblockconnectors,see
  guresII.E.1,II.E.6orII.E.7.
CAUTION: The connectors require only a small screwdriver or
a pen to push on the release levers. The release levers may
be broken or damaged if not pushed straight toward the circuit
board. DO NOT push the release levers sideways.
Theeasiestmethodofconnectingtherelayisshowningures
II.E.1, and II.E.6. These show how the dry contact relay can use
incoming power to activate a controlled device (alarm, solenoid
valve, etc.) of 10 amps or less.
For24VACapplications,theMyronL®Company offers a 115
VACto24VACtransformer,Model#VR,seegureII.E.7.Other
voltages must be user-supplied.
6. CONNECTING DISPLAY HARNESS TO DISPLAY
If the installation required the removal of the display harness
from the display (OEM installation requires connection), the
following procedure will ensure it is reinstalled without damaging
the display.
WARNING: THE DISPLAY WILL BE IRREPARABLY
DAMAGED IF THE HARNESS IS INSTALLED UPSIDE-DOWN
OR MISALIGNED. THE HARNESS MUST BE INSTALLED AS
SHOWN IN FIGURE II.E.8.
1. Grasp connector and align wires DOWN on display or
  withthesmalledgeofthedisplayasshowningure 
II.E.8.
2. Press connector onto display pins. Ensure pins are
aligned or they may become bent. Wiggle connector
slightly “end to end” if necessary.
DEVICE
TO BE
CONTROLLED
POWER
SOURCE
MONITOR / CONTROLLER
CIRCUIT BOARD
COM
NO
CM
NO
NC
RELAY
RELAY
TERMINAL BLOCK
OPT.
FLOW
SWITCH
X
DEVICE
TO BE
CONTROLLED
COM
NO
115VAC
POWER
SOURCE
CM
NO
NC
RELAY
VR
RELAY
TERMINAL BLOCK
115 to 24VAC
TRANSFORMER
MONITOR/CONTROLLER
CIRCUIT BOARD
OPT.
FLOW
SWITCH
X
DISPLAY CONNECTION
DISPLAY
HARNESS
DISPLAY
Figure II.E.6
PANEL MOUNTED DISPLAY
REAR VIEW
Figure II.E.8
Figure II.E.7

F. 0-10 VDC RECORDER OUTPUT
The0-10VDCoutputisdesignedtogivetheuserthecapability
of sending a signal to a remote meter, recorder, PLC or SCADA
system.
1. CONNECTION
1. Place the user supplied interface cable and watertight
  cablerestraintintotheenclosure’sappropriateaccess
hole. Skip for OEM.
 2. ConnecttheRecorder’splus(+)andminus(-)terminal
  wirestotheRecorderoutputconnectors.(Seegure
II.E.1.)
 3. RefertoSectionV.C.1.bfortheprocedurestocalibrate
  the0-10VDCvoltageoutput.
2. VOLTAGE DIVIDER
A voltage divider gives the user the ability to scale or tailor the
output to a particular need or requirement due to the input of
anotherdevice,i.e.theoutputoftheMainCBis0-10Vwhilethe
inputrequirementofaparticularrecordingdeviceis0-5V.
a. INSTALLATION
Briey—
Tworesistorsareinstalledacrossthe0-10Voutput.
The output is recalibrated to required voltage.
Requirements
Select two (2) resistors as listed;
  For0-5VOutputboth“A&B”are2KResistors.
  For0-1VOutput“A”isa9Kresistorand“B”isa1Kresistor.
WARNING: BEFORE STARTING, IF MONITOR/
CONTROLLER IS INSTALLED, ENSURE THE POWER IS
OFF. FAILURE TO DO SO COULD CAUSE DAMAGE TO
THE INSTRUMENT, AND COULD BE HARMFUL OR FATAL
TO PERSONNEL. ONLY QUALIFIED PERSONNEL SHOULD
INSTALL ELECTRICAL EQUIPMENT.
Physical
If the front panel has all ready been removed from the enclosure
skip to #3.
1. Using a standard slot screwdriver remove the four (4)
screws on the front panel.
2. Carefully wiggle the front panel to loosen and pull
gently toward you. Do not pull more than about
8 inches/20CM or you could damage the wiring
harness.
3. Turn the front panel around so that the back side is
facing you and set aside for now.
4. Solder two selected resistors together as shown in
  gureII.F.1.
 5. Attachleadstorecordingdeviceasshowningure 
II.F.1.
 6. Attachresistorsto0-10VOutputasshowningure 
II.F.2.
Ensure resistors and leads DO NOT short to each
other or to any part of the CB assembly.
7. Recalibration is required, see Calibration Procedures,
  sectionV.C.
Reassembly
 1. Carefullyreinstallthefrontpanel,bottomrst,ensure
no wires have been pinched.
2. Reinstall the four (4) screws and tighten.
3. To operate, turn power ON.
0-10V Output
+
-
A
B
+
-
Recording
Device
FS SW
BK WT RD GN NU R- R+
3S
SENSOR LEADS
CAL
0-10VDC
OUTPUT
NEW OUTPUT
AS SELECTED
+-
Main CB Assembly
15
Figure II.F.1
Figure II.F.2
!
CAUTION - READ FOLLOWING CAREFULLY

16
G. RE-RANGE YOUR MONITOR/CONTROLLER
(Range Module Installation)
1. DESCRIPTION
The 750 Series II Monitor/controllers have been designed for
easyeldre-rangeability.TheRangeModuleconsistsofa16
pin Header that plugs into a 16 pin socket.
For available ranges, see Range Selection Guide I.G. When
making large range changes, i.e. 5000 ppm to 50 ppt, a different
sensor may also be required as noted in the Range Selection
Guide.OrderRangeModulebyaddingtheprex“RM”tothe
range number as in examples below.
Conductivity/TDS Range Modules —
RMXXX i.e. = RM121 is a 0-2000µS
Resistivity Range Modules —
  RMXX   i.e.=RM11   isa0-20MΩ
NOTE: Some OEM models may not be re-ranged being
originallymanufacturedwithaxedrange.Ifyourapplication
requiresre-ranginganOEMmodel,rstcontactthesystem
manufacture for help. The Myron L®Company may re-range or
exchange your instrument at a cost.
2. INSTALLATION
Briey-
The new Range Module simply replaces the Range Module
presentlyinstalled,seegureII.G.1.
Multiplier label is added to analog models*.
Type label may be required if changing from Microsiemens to
Millisiemens or PPM/PPT.
The Full Scale reading is recalibrated.
IMPORTANT NOTES:
1. When changing ranges on Digital Monitor/ controllers
with the -45 option (4 1/2 digit backlit display), the following
modications may be required to the range module; RM123
thru 128 and RM16 require pin number 9 be removed or
bent toward the side, see Fig. II.G.2. On RM117 thru 122 a
jumper wire must be soldered to the RM, see Fig. II.G.3.
*2. Analog Monitor/controllers may require a scale change.
See section II.G.3 for the specic instructions.
WARNING: BEFORE STARTING, IF MONITOR/
CONTROLLER IS INSTALLED, ENSURE THE POWER IS
OFF. FAILURE TO DO SO COULD CAUSE DAMAGE TO
THE INSTRUMENT, AND COULD BE HARMFUL OR FATAL
TO PERSONNEL. ONLY QUALIFIED PERSONNEL SHOULD
INSTALL OR SERVICE ELECTRICAL EQUIPMENT.
Physical
NOTE: When opening instrument, remove front cover with care;
a ribbon cable connects the front panel and main board. If the
front panel has already been removed from the enclosure skip
to #4.
1. Using a standard slot screwdriver remove the four (4)
screws on the front panel.
2. Carefully wiggle the front panel to loosen and pull
gently toward you. Do not pull more than about
8 inches/20CM or you could damage the wiring
harness.
3. Turn the front panel around so that the back side is
facing you and set aside.
4. Locate and remove existing Range Module from MAIN
  CircuitBoard,asshowningureII.G.1.Itisnoteasy
to remove, it was designed to stay in place under
adverse conditions.
5. With the pointer up, carefully align the new Range
Module to the socket on the MAIN Circuit Board as
  showningureII.G.1.
 6. Pressrmlyintoplace.
7. For analog models, add multiplier label to front panel.
  SeeguresII.G.10andII.G.11forsuggestedlocations.
In some cases changing the meter scale will be
necessary. See Changing Analog Meter Scale, section
II.G.3.
8. Recalibrate, see CALIBRATION PROCEDURES,
  sectionV.C.
Main CB Assembly
Figure II.G.1
REMOVE
PIN #9
UP
DIGITAL 4 1/2 DIGIT LCD
MONITOR/CONTROLLERS ONLY
ADD JUMPER
CONNECTING
PINS 7 & 10
UP
RANGE MODULE
Bottom View
FIGURE II.G.2 FIGURE II.G.3
!
CAUTION - READ FOLLOWING CAREFULLY
BK WT RD GN NU R- R+
CHS
GND
UP
}
HYS1SP1
FUSE*
115/
230 PWR C GD NC NO CM
DIS
CAL
3S
PA RA
INC
DEC
SPC
TRANSFORMER
RANGE
MODULE
751 756
752 757
753 758
754 759
FS SW
FULL SCALE
PUSH TO TEST
0-10VDC
OUTPUT
-121
2000µS
POINTER
REMOVE TO INSTALL SECOND RELAY