Myron L 900 Series User manual

900 Series Multi-Parameter
Monitor/Controller™
Operation Manual

900 Series Operation Manual – 900OM r03-20
Page 2
REVISION HISTORY:
Rev.
Date Released
Description of Change
r03-20
01-MAR-2020
Initial Release
To download the most up to date version of this manual go to www.myronl.com
IDENTIFICATION RECORDS
Model Number: _____________________________________________________________________
Serial Number: ______________________________________________________________________
(This number appears on the label located on the side of the instrument.)
Date of Purchase: ____________________________________________________________________
(This is the warranty start date.)
Installation Location: _________________________________________________________________
Asset ID (user assigned): ______________________________________________________________
COPYRIGHT INFORMATION
This document is copyrighted by Myron L®Company and shall not be reproduced or copied without expressed
written authorization from Myron L®Company.
The information contained within this document is subject to change without notice. Myron L®Company does not
guarantee the accuracy of the information.

900 Series Operation Manual – 900OM r03-20
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ESSENTIAL INFORMATION
1. Important User Information:
In no event will Myron L®Company be responsible or liable for indirect or consequential damages resulting from
the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many
variables and requirements associated with any particular installation, Myron L®Company cannot assume
responsibility or liability for actual use based on the examples and diagrams.
Throughout this manual, when necessary, we use notes to make you aware of safety considerations.
Alert
Meaning
Signifies an important note.
CAUTION
Identifies information about practices that should be taken to avoid the potential for damage to,
or loss of use of, the 900 Series Monitor/Controller or other equipment or avoid a safety hazard
to the user.
WARNING
Identifies information about practices or circumstances that can cause a significant likelihood
of damage to, or loss of use of, the 900 Series Monitor/Controller or other equipment, personal
injury or death, property damage, or economic loss.
Identifies information that is critical for successful application and understanding of the product.
Indicates a possible electric shock hazard may exist.
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
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. Install all wiring to comply with applicable electrical codes.
WARNING
This Instrument contains NO OPERATOR SERVICEABLE PARTS!
WARNING
This instrument may not be used to measure categories, II, III, or IV (IEC 61010-2-30 Annex AA)
Main Power Circuits.
It has been designed without a rated measuring category and may only be used at direct voltage
circuits less than or equal to the voltage levels specified in the technical specifications for each
input or output.
WARNING
Operating safety is no longer assured if the instrument is modified or altered in any way. This
instrument may only be opened by authorized service personnel.
Operating the instrument at a higher voltage than specified in the technical specifications may
destroy or permanently damage it.
WARNING
The 900 Series Multi-Parameter Monitor/Controllers operate on 12-24 VDC or 24 VAC. Before
applying power ensure the input power supply is correct. Failure to do so is beyond the
responsibility of the Myron L®Company.
CAUTION
All environmental specifications listed in this manual apply equally to the 900 Series Multi-
Parameter Monitor/Controller and all of its parts.
WARNING! These products can expose you to chemicals including Di(2-ethylhexyl)phthalate
(DEHP), which is known to the State of California to cause cancer and birth defects or other
reproductive harm. For more information go to www.P65Warnings.ca.gov.

900 Series Operation Manual – 900OM r03-20
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2. Trademark Information:
Brand or product names are trademarks or registered trademarks of their respective owners.
• Myron L®is a registered trademark of the Myron L®Company
• 900 Series Multi-Parameter Monitor/Controller™and 442 Natural Water Standard™are trademarks of the
Myron L®Company.
3. FCC Part 15 Statement:
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to FCC
Part 15, Subpart B.
• These limits are designed to provide reasonable protection against harmful interference when the
equipment is operated in a commercial environment.
• This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in
accordance with the instruction manual, may cause harmful interference to radio communications.
• Operation of this equipment in a residential area is likely to cause harmful interference in which case the
user will be required to correct the interference at his or her own expense.
4. EN / IEC / EU Compliance:
The Myron L®Company declares under our sole responsibility that this instrument complies with the
requirements, principal elements and objectives of the following:
• EN 61326-1 – Electrical Equipment for Measurement and Laboratory Use, EMC requirements.
• IEC 61010-1 – Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory
use.
• 2015/863/EU – Restrictions on Hazardous Substance (RoHS 3) Directive.
5. CAUTION – European Users:
This is a Class A product. In a domestic environment this product may cause radio interference in which case the
user may be required to take adequate measures.
6. WARNING – Electromagnetic Compatibility:
The connection of non-shielded equipment interface cables to this equipment will invalidate FCC EMI and European
Union EMC compliance and may result in electromagnetic interference and/or susceptibility levels which are in
violation of regulations which apply to the legal operation of this device. It is the responsibility of the system
integrator and/or user to apply the following directions, which relate to installation and configuration:
• All interface connections must be made with shielded cables. Shields must be connected as described in
this manual.
• Protective measures for power and interface cables as described within this manual must be applied.
• Do not leave cables connected to unused interfaces or disconnected at one end.
• Changes or modifications to this device not expressly approved by the manufacturer could void the user's
authority to operate the equipment.
7. Disposal:
DISPOSAL!
At the end of its service life, the device and any accessories do not belong in the trash. These
items are made from materials that can be reclaimed through recycling.
Dispose of the device, accessories, and packaging material as required by regulations and in
an environmentally sound manner!
The local and country-specific laws and regulations for handling and disposing of waste must
be observed.

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HOW TO USE THIS MANUAL:
The 900 Series Multi-Parameter Monitor/Controller Operation Manual was written to be most useful to all users,
from novice to skilled professional.
Most functions are programmed to prompt you through required settings, simply make selections and tap the
NEXT button. Subsequent changes to a function’s settings will allow you to select only those fields you wish to
change.
Read this operating manual before putting the device into service.
Keep the operating manual at a location that is readily accessible to all users.
The basic setup steps:
• Install the base unit
• Install all sensors
• Connect all sensors, inputs, and output wiring to base unit
• Power up the 900 and go through the Initial Setup procedure
• Program Detailed Operating Settings custom to your application
• Calibrate as necessary
If you have any questions regarding this manual or need additional information, please contact our Technical
Sales personnel at [e-mail] or call 760-438-2021.

900 Series Operation Manual – 900OM r03-20
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Table of Contents
I.!INTRODUCTION ....................................................................................................................10!
A.!Scope......................................................................................................................................10!
B.!Benefits ..................................................................................................................................10!
C.!Applications...........................................................................................................................10!
D.!Features..................................................................................................................................10!
II.!SPECIFICATIONS .................................................................................................................11!
III.!ORDERING INFORMATION.................................................................................................17!
A.!900 Series Models ................................................................................................................17!
1.!900 Series Model Features ..........................................................................................17!
B.!Sensors ..................................................................................................................................18!
1.!Conductivity/Resistivity/TDS/Salinity Sensors............................................................18!
2.!Pre-amplified pH/ORP Sensors (for use with the 900 Series pH/ORP Input)..........19!
3.!BNC Style pH/ORP Sensors (for use with the 900 Series mV Input).......................19!
4.!Temperature Sensors ...................................................................................................20!
5.!Flow Meter .....................................................................................................................20!
IV.!INSTALLATION .....................................................................................................................21!
A.!Unpacking and Inspection of Equipment ........................................................................21!
B.!Installing the 900 Series Multi-Parameter Monitor/Controller......................................22!
1.!Select a Mounting Site..................................................................................................23!
2.!Panel Mounting..............................................................................................................23!
C.!Installing Sensors.................................................................................................................26!
1.!Installing Conductivity/Resistivity/TDS/Salinity Sensors............................................26!
2.!Installing pH/ORP Sensors...........................................................................................27!
D.!Electrical Installation ...........................................................................................................28!
1.!Wiring Inputs and Outputs to the Connectors.............................................................29!
2.!Install Ferrite Bead on Power Cable............................................................................29!
3.!Connecting Inputs, Outputs, and Power to the 900 ...................................................30!
4.!Back Panel Connector Locations.................................................................................30!
V.!INITIAL SETUP ......................................................................................................................31!
A.!Date and Time .......................................................................................................................31!
B.!Location..................................................................................................................................32!
C.!Set Up Password Security ..................................................................................................32!
D.!Enable/Disable Input Channels..........................................................................................33!
E.!Screen Layout .......................................................................................................................34!
VI.!DETAILED OPERATING SCREEN......................................................................................36!
VII.!DETAILED OPERATING SETTINGS ..................................................................................37!
A.!Conductivity, Resistivity, TDS or Salinity........................................................................37!
1.!Sensor Settings .............................................................................................................37!
2.!Select Measurement Type ...........................................................................................38!
3.!Select Solution Type.....................................................................................................38!
B.!pH/ORP (Pre-amplified) .......................................................................................................39!
1.!Sensor Settings, pH/ORP.............................................................................................39!
2.!Select Measurement Type ...........................................................................................39!
C.!mV Input (BNC) .....................................................................................................................40!

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1.!Select Measurement Type ...........................................................................................40!
D.!RTD Temperature Input .......................................................................................................41!
E.!Temperature Unit of Measure.............................................................................................41!
F.!4-20 mA Input ........................................................................................................................42!
1.!Select Measurement Type ...........................................................................................42!
2.!Measurement Settings, 4-20 mA .................................................................................42!
G.!Flow / Pulse Input.................................................................................................................43!
1.!Sensor Settings, Flow/Pulse Input...............................................................................43!
2.!Select Measurement Type ...........................................................................................43!
3.!Volume Reset ................................................................................................................44!
H.!Flow Switch Input .................................................................................................................44!
I.!Relays and Alarms ...............................................................................................................44!
1.!Relay Wiring Options ....................................................................................................45!
2.!Relay Settings ...............................................................................................................46!
3.!Alarm Settings ...............................................................................................................47!
4.!Reset Latching Alarms..................................................................................................48!
5.!Testing Relays and Alarms ..........................................................................................49!
6.!Relay/Alarm OVERRIDE Mode....................................................................................49!
7.!Relay/Alarm Settings Reset .........................................................................................50!
8.!Relay/Alarm Visual Indicators ......................................................................................50!
VIII.!DETAILED SYSTEM SETTINGS .........................................................................................52!
A.!Date and Time .......................................................................................................................52!
B.!Location..................................................................................................................................52!
C.!Passwords and Security .....................................................................................................53!
1.!Administrator Password Setup.....................................................................................53!
2.!Operator Access Setup.................................................................................................54!
3.!Operator Password Setup ............................................................................................55!
4.!Change Administrator Password .................................................................................55!
5.!Change Operator Password.........................................................................................55!
6.!Reset Administrator Password.....................................................................................56!
7.!Reset Operator Password ............................................................................................56!
D.!Input Channels......................................................................................................................56!
1.!Enable/Disable Input Channels....................................................................................56!
IX.!DISPLAY SETTINGS.............................................................................................................57!
1.!Screen Layout ...............................................................................................................57!
2.!All Channels Screen Layout.........................................................................................59!
3.!Locking/Unlocking the Single Channel Screen...........................................................59!
4.!Screen Configuration ....................................................................................................59!
5.!Brightness......................................................................................................................60!
6.!Night Mode.....................................................................................................................60!
7.!Timeout Settings ...........................................................................................................61!
X.!ADVANCED SETTINGS........................................................................................................62!
A.!0-10V Recorder Output........................................................................................................62!
1.!Programming the 0-10V Recorder Output ..................................................................62!
2.!Voltage Divider ..............................................................................................................63!
B.!4-20mA / 0-20mA Output (Model 900M-3C only).............................................................63!
C.!Derived Measurement..........................................................................................................65!

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1.!Percent (%) Rejection...................................................................................................65!
D.!User Mode Tempco and Ratio Settings............................................................................66!
1.!Selecting the User Mode Solution Type......................................................................66!
2.!Disable or Customize Temperature Compensation ...................................................67!
3.!Enter Custom Conductivity to TDS Ratio....................................................................67!
E.!Factory Reset ........................................................................................................................67!
XI.!CALIBRATION .......................................................................................................................68!
A.!Conductivity, TDS, or Salinity Calibration.......................................................................68!
1.!Wet Calibration with Standard Solution.......................................................................68!
2.!Transfer Standard Method of Calibration....................................................................69!
3.!FAC CAL (Reloading Factory Calibration)..................................................................69!
B.!Resistivity Calibration .........................................................................................................70!
1.!Transfer Standard Method of Calibration....................................................................70!
2.!Sensor Substitute..........................................................................................................71!
3.!FAC CAL (Reloading Factory Calibration)..................................................................72!
C.!pH Calibration .......................................................................................................................73!
1.!pH Calibration with Buffer Solution(s) .........................................................................73!
2.!Transfer Standard Calibration......................................................................................75!
3.!FAC CAL (Reloading Factory Calibration)..................................................................76!
D.!ORP Calibration ....................................................................................................................77!
1.!ORP Calibration with Standard Solution .....................................................................77!
2.!Transfer Standard Calibration......................................................................................77!
3.!FAC CAL (Reloading Factory Calibration)..................................................................78!
E.!Temperature Calibration .....................................................................................................79!
1.!Wet Calibration..............................................................................................................79!
2.!Sensor Substitute, Temperature..................................................................................80!
3.!FAC CAL (Reloading Factory Calibration)..................................................................81!
F.!4-20mA Output Calibration.................................................................................................82!
1.!Electronic Calibration....................................................................................................82!
2.!FAC CAL (Reloading Factory Calibration)..................................................................83!
G.!0-10 VDC Recorder Output Calibration ............................................................................83!
1.!Electronic Calibration....................................................................................................83!
2.!FAC CAL (Reloading Factory Calibration)..................................................................84!
XII.!REFERENCE INFORMATION..............................................................................................84!
A.!Temperature Compensation (Tempco) of Aqueous Solutions....................................84!
1.!Standardized to 25°C....................................................................................................84!
2.!Tempco Variation ..........................................................................................................84!
3.!Example of 2 Different Solution Selections and the Resulting Compensation ........85!
4.!Chart of Comparative Error ..........................................................................................85!
5.!Other Solutions..............................................................................................................85!
B.!Conductivity Conversion to Total Dissolved Solids (TDS)...........................................85!
1.!How it’s Done ................................................................................................................85!
2.!Solution Characteristics................................................................................................86!
3.!When does it make a lot of difference?.......................................................................86!
C.!Temperature Compensation (Tempco) and TDS Derivation ........................................86!
1.!Conductivity Characteristics.........................................................................................86!
2.!Finding the Tempco of an Unknown Solution.............................................................87!
3.!Finding the TDS Ratio of an Unknown Solution.........................................................87!

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D.!pH, ORP and Temperature Relationships........................................................................87!
1.!pH ...................................................................................................................................87!
2.!ORP/Oxidation-Reduction Potential/REDOX..............................................................88!
3.!pH and ORP SENSOR CAUTIONS ............................................................................89!
E.!Relay and Alarm Trigger, Set Point and Hysteresis Functionality..............................90!
XIII.!MAINTENANCE .....................................................................................................................92!
A.!900 Series Multi-Parameter Monitor/Controller Base Unit............................................92!
1.!Cleaning the Display.....................................................................................................92!
2.!Calibrating the Display Touch Screen.........................................................................92!
B.!Sensor Care...........................................................................................................................92!
1.!pH and ORP Sensors ...................................................................................................92!
2.!Conductivity, TDS, Resistivity, and Salinity Sensors .................................................93!
XIV.!TROUBLESHOOTING...........................................................................................................94!
A.!Troubleshooting Chart ........................................................................................................94!
B.!Frequently Asked Questions..............................................................................................94!
C.!System Overview Screen....................................................................................................95!
XV.!ACCESSORIES......................................................................................................................96!
A.!Standard Solutions and Buffers ........................................................................................96!
1.!Conductivity/TDS Standard Solutions .........................................................................96!
2.!pH and ORP Buffer Solutions ......................................................................................96!
3.!Ordering Information .....................................................................................................97!
B.!NIST Certification .................................................................................................................97!
C.!Resistivity Sensor Substitutes ..........................................................................................97!
D.!Temperature Sensor Substitutes ......................................................................................97!
E.!Alarms.....................................................................................................................................98!
1.!Terminal Block Locations .............................................................................................98!
2.!Remote Alarm - RA™ ...................................................................................................98!
3.!Piezo Electric Alarm....................................................................................................100!
4.!Connecting to Your Own Alarm .................................................................................101!
F.!Mounting Brackets .............................................................................................................102!
G.!Power Adapter.....................................................................................................................102!
1.!Specifications ..............................................................................................................102!
XVI.!GLOSSARY ..........................................................................................................................103!
XVII.!WARRANTY .........................................................................................................................105!

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I. INTRODUCTION
Myron L®Company’s new 900 Series Multi-Parameter Monitor/Controllers combine accuracy, reliability, simplicity,
and flexibility. The easy to read, 3.5” color TFT display with resistive touch-screen and user intuitive GUI
(Graphical User Interface) allows easy and complete programmability of the instrument all from the LCD touch
screen. These highly accurate instruments have the ability for simultaneous monitoring and controlling of multiple
inputs/outputs.
Since temperature compensation (TC) is at the heart of accurate water measurement, all 900 Series
Monitor/Controllers feature a highly refined and precise TC correction algorithm based on years of proven
experience. Conductivity, TDS, Resistivity, Salinity, and pH readings are corrected to 25˚C. The TC feature may
be turned off to conform to USP requirements.
A. Scope
This operation manual provides the information necessary to install, customize settings, operate, and maintain the
Myron L®Company's 900 Series Multi-Parameter Monitor/Controllers.
B. Benefits
• Affordable
• Ease of Operation
• Low Maintenance
• Ensure Product Quality
• Prevent Equipment Damage
• Reduce Waste
• Protect the Environment
C. Applications
• Power Plants
• Agriculture
• Waste Water Management
• Boilers & Cooling Towers
• Reverse Osmosis
• Deionization (Dl)
• Electronics
• Pharmaceuticals
• Laboratories
• Paper and Pulp
• Process Control
• Seawater Desalination
• Environmental
• Potable Water
• Hydroponics
• Aquaculture
• Food and Beverage Processing
• Plating
• Swimming Pools & Spas
• Printing
• Brewing
• Distillation
• Bleach Manufacturing
• Coffee Industry
• Reduction of Chromate Waste
D. Features
• Flexibility to Meet any Application
• Mobile Device Style GUI and OS
• Large, Sharp, Color Touch Screen
(3.5” QVGA LCD)
• Customizable Screen Layout
• Quick, Easy Installation
• Simultaneous Monitoring of Multiple Sensors
Including up to 7 Inputs:
2 – Conductivity/Resistivity/TDS/Salinity
1 – Pre-amplified pH/ORP
1 – BNC pH/ORP/mV
1 – 4-20 mA Input
1 – Flow Rate and Volume Totalizer,
Pulse Counter/Frequency Counter
1 – Additional RTD Temperature Input
• % Rejection
• ¼DIN Size Chassis
• Password Security Features
• Up to 3 Alarm/Control Relays, Configurable
• 0-10V Recorder Output, Fully Scalable
• 4-20/0-20 mA Isolated Output, Fully Scalable
• Up to 2 Remote Alarm Outputs
• Flow Switch Input
• Digital Calibration (no need to remove the front
panel or adjust potentiometers)
• 3 Temperature Compensation Standards for
Greatest Accuracy in Diverse Applications (KCl,
NaCl, and 442 Natural Water™)
• User Adjustable Temperature Compensation
(0 - 10%/°C), can be Disabled for Non-
compensated Readings

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II. SPECIFICATIONS
The 900 Series Multi-Parameter Monitor/Controller provides simultaneous measurement and control of
multiple input and output channels. The specifications of the various features are listed below:
Power Supply
Low voltage, 12-24 VDC, 1A/24 VAC, 1A input
Optional 100-240 VAC input power adaptor, available from Myron L®Company
WARNING
To maintain the 900 Series Multi-Parameter Monitor/Controller IEC 61010-1 safety rating, only
use external power supplies / adapters that are also IEC/UL 61010-1 or IEC/UL 60950-1 rated
to the full operating temperature range of the instrument.
Fuses
Built-in fusible link (no user-replaceable fuses): 2 Amp 250 VAC
Display / User interface
Display: 3.5” Color LCD, high brightness, TFT
Resistive Touch Screen
Brightness: Adjustable from 0-100%
Status LED: Tri-color
Conductivity/Resistivity/TDS/Salinity Measurements
[Terminal Blocks: COND/RES1 and COND/RES2]
a. Conductivity
Range: 0 µS – 200 mS
Resolution: 0.01 (<100 µS)
0.1 (<1000 µS)
1 (<10,000 µS)
0.01 (<100 mS)
0.1 (≤200 mS)
Accuracy: ±1% of reading (factory calibration)
Units: µS/mS (automatic)
Temperature Compensation:
Automatic compensation on KCl, 442™ and NaCl solutions from 0-71˚C (32-160˚F)
User adjustable temperature compensation: 0-10%/˚C
Adjustable Conductivity/TDS Ratio Factor: 0.20 – 7.99
Cell Constant: User adjustable
Cable Length Compensation: User adjustable
b. Total Dissolved Solids (TDS)
Range: 0 ppm – 200 ppt
Resolution: 0.01 (<100 ppm)
0.1 (<1000 ppm)
1 (<10,000 ppm)
0.01 (<100 ppt)
0.1 (≤200 ppt)
Accuracy: ±1% of reading (factory calibration)
Units: ppm/ppt (automatic)
Temperature Compensation:
Automatic compensation on KCl, 442™ and NaCl solutions from 0-71˚C (32-160˚F)
User adjustable temperature compensation: 0-10%/˚C
Adjustable Conductivity/TDS Ratio Factor: 0.20 – 7.99
Cell Constant: User adjustable
Cable Length Compensation: User adjustable

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Page 12
c. Resistivity
Range: 10 kΩ– 40 MΩ
Resolution: 0.01 (<100 kΩ)
0.1 (<1000 kΩ)
0.01 (<10 MΩ)
0.1 (≤40 MΩ)
Accuracy: ±1% of reading (factory calibration)
Units: kΩ/MΩ(automatic)
Temperature Compensation:
Automatic compensation on KCl, 442™ and NaCl solutions from 0-71˚C/32-160˚F
User adjustable temperature compensation: 0-10%/˚C
Cell Constant: User adjustable
Cable Length Compensation: User adjustable
d. Salinity
Range: 0 – 200 ppt
Resolution: 0.001 (<10 ppt)
0.01 (<100 ppt)
0.1 (≤200 ppt)
Accuracy: ±1% of reading (factory calibration)
Units: ppt
Temperature Compensation:
Automatic compensation on KCl, 442™ and NaCl solutions from 0-71˚C (32-160˚F)
User adjustable temperature compensation: 0-10%/˚C
Cell Constant: User adjustable
Cable Length Compensation: User adjustable
pH/ORP
[Terminal Block: pH / ORP]
a. pH Measurements
Range: 0 – 14 pH
Resolution: 0.01 pH
Accuracy: ±0.01 pH (post solution calibration)
Temperature Compensation:
Automatic compensation per Nernst equation, referenced to 3.5 M KCl Ag/AgCl
reference electrode
pH temperature compensation may be turned off by selecting pH (TC Off)
Cable Length Compensation: User adjustable
b. ORP Measurements
Range: ±2000 mV
Resolution: 1 mV
Accuracy: ±2 mV (post solution calibration)
Units: mV
Temperature Compensation: N/A
RTD Input, Temperature Measurements
[Terminal Block: RTD]
Range: 0-250˚C
Resolution: 0.1˚C/˚F
Accuracy: ±0.1˚C
Units: ˚C/˚F (User selectable)
Input Type: RTD, 1000 Ω
Cable Length Compensation: User adjustable

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mV Input, DC Measurements
[BNC Connector: mV IN]
May be configured to display in ORP/mV or pH (w/TC) or pH (TC Off).
NOTE: The shorting BNC connector cap (included) must be installed when there is no sensor
connected to the mV input.
a. pH Measurements
Range: 0-14 pH
Resolution: 0.01 pH
Accuracy: ±0.01 pH
Units: pH
Temperature Compensation (requires temperature sensor installed in the RTD input):
Automatic compensation per Nernst equation, referenced to 3.5 M KCl Ag/AgCl
reference electrode
pH temperature compensation may be turned off by selecting pH (TC Off)
b. ORP/mV Measurements
Range of Measurement: +/- 2000 mV
Resolution: 1 mV
Accuracy: ±2 mV
Units: mV
Temperature Compensation: N/A
0/4-20 mA Input, Loop Powered, Non-isolated, DC Measurements
[Terminal Block: 4-20 mA IN]
Range of Measurement: 0/4-20 mA
Resolution:
Current Mode: 0.01 mA
Measurement Mode: 0.01 (<100)
0.1 (<1000)
1 (≥1000)
Accuracy: ±1% of reading
Units:
Current Mode: mA
Measurement Mode: User selectable (gpm, gph, lps, lpm, lph, Gal, Ltr, %, PSI, NTU, µS,
mS, ppm, ppt, mV, V, ˚C, ˚F, Ω, kΩ, MΩ, mA, Hz, kHz)
Temperature Compensation: Not available
Input Impedance: < 600 Ω
Galvanic Isolation: Not available
Flow / Pulse Input Measurements
[Terminal Block: FLO/PULSE]
Range of Measurement: 0.5 to 50,000 pulses per second
Resolution: 0.001 (<10)
0.01 (<100)
0.1 (<1000)
1 (≥1000)
Accuracy: ±1 Hz or ±1% of reading
Units: Hz, KHz (automatic)
Temperature Compensation: N/A
Input Type:
Schmitt trigger, TTL input
Open collector
Dry Contact, debounced

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Page 14
Flow Switch/Kill Switch Input
[Terminal Block: FLOW SW]
Input Type:
TTL Input
Open Collector
Dry Contact
NOTE: The jumper (included) must be installed in the terminal block connector if there is no
flow/level switch installed.
Relay Outputs
WARNING
Use caution when selecting cabling for Relay Outputs. Use at least 14 gauge
conductors.
[Terminal Block: RELAY #1, RELAY #2 and RELAY #3]
Contact Type: Type 1C, normally open/normally closed/common
Contact Rating
Max Current: 5 Amp @ 30 VDC
8 Amp @ 250 VAC 50/60 Hz
Max Voltage: 30VDC/250VAC max at 50/60 Hz
Dielectric Strength: 750VAC
Operate Time: 10 msec
Control Capability
1 to 3 Relays (1 relay on model 900M-1C, 3 relays on model 900M-3C)
Set point: 0-100% of measurement range
Hysteresis: 0.3-5% of reading
2-100 mV ORP
Triggering conditions:
Rising above a set point
Falling below a set point
Within Window of a measurement
Out of Window of a measurement
Warning: Approaching +/- 10% of set point
Visual Indicators
Screen background color and front bezel LED color status indicators:
Blue indicates the measurement is within normal operating range
Yellow indicates the measurement value is within warning range
Red indicates the measurement value has reached or gone beyond the set point

900 Series Operation Manual – 900OM r03-20
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Alarm Outputs
[Terminal Block: RA #1 AND RA #2]
Compatible Alarm Type
Piezo Electric Alarm Model PAO (See “ACCESSORIES, Piezo Electric Alarm”, page 100)
Remote Alarm Model RA (See “ACCESSORIES, Remote Alarm – RA™”, page 98)
User Supplied Alarm
Alarm Output Electrical Rating
Max Current: 20 mA DC
Max Voltage: 20V DC
Control Capability
1 to 2 Alarms (1 alarm on model 900M-1C, 2 alarms on model 900M-3C)
Set Point: 0-100% of measurement range
Hysteresis: 0.3-5% of reading
2-100 mV ORP
Triggering Conditions:
Rising above a set point
Falling below a set point
Within Window of a measurement
Out of Window of a measurement
Warning: Approaching +/- 10% of set point
Visual Indicators:
Screen background color and front bezel LED color status indicators:
Blue indicates the measurement is within normal operating range
Yellow indicates the measurement value is within warning range
Red indicates the measurement value has reached or gone beyond the set point
0-10 VDC Output, Measurement output as voltage
[Terminal Block: REC O/P]
Output: Output voltage: 0-10V
Output current capability: 20 mA max
Accuracy: +/- 1% of reading
0/4-20mA Output, Measurement output as current with isolation
[Terminal Block: 4-20mA OUT]
Output: Isolated Output current capability: 0/4-20 mA max
Compatible with loop powered or self-powered current receiving device
Loop Power supply input range: 20-36 VDC
Accuracy: +/- 1% of reading
Mechanical Specifications:
Operating Temperature: 0 – 60 °C / 32 – 140 °F
Maximum Operating Altitude: 2000 meters (6560 feet)
Maximum Humidity: <90% RH, Non Condensing
Storage Temperature: 0 – 75 °C / 32 – 167 °F
Weight: 900M-1C: 0.85 lb / 0.39 kg
900M-3C: 1.0 lb / 0.45 kg

900 Series Operation Manual – 900OM r03-20
Page 16
Housing Specifications:
Industrial standard ¼DIN chassis/panel cutout
Easy access terminal connections to sensors and control outputs
Enclosure Material: PC/ABS
Enclosure Rating: IP65/NEMA 4X (front/face only), IP20 (housing)
Dimensions (housing, without connectors):
NOTE: The above dimensions do not reflect panel cutout dimensions or panel depth necessary
for connectors or cabling with service loop. See page 23 for panel cutout dimensions.

900 Series Operation Manual – 900OM r03-20
Page 17
III. ORDERING INFORMATION
A. 900 Series Models
Order Part #
Description
900M-1C
Monitor/Controller with 1 Relay, 1 Alarm
900M-3C
Monitor/Controller with 3 Relays, 2 Alarms, and 4-20 mA Output
1. 900 Series Model Features
900M-1C
900M-3C
INPUTS
COND / RES 1
Conductivity, Resistivity, TDS, or Salinity Sensor Input
✔
✔
COND / RES 2
Conductivity, Resistivity, TDS, or Salinity Sensor Input
✔
✔
pH / ORP
Myron L®Company Pre-amplified pH or ORP Sensor Input
✔
✔
mV IN
BNC Style mV Model Sensors (pH/ORP/mV)
✔
✔
FLOW SW
Flow Switch Input
✔
✔
4-20 mA IN
4-20 mA Signal Input
✔
✔
FLOW / PULSE
Flow Rate and Volume Totalizer, Pulse/Frequency Counter
✔
✔
RTD
Temperature Sensor Input (1000 ΩRTD)
✔
✔
24 VAC / 12-24 VDC
Power Supply Input
✔
✔
OUTPUTS
RELAY #1
Normally Open or Normally Closed Relay Output
✔
✔
RELAY #2
Normally Open or Normally Closed Relay Output
✔
RELAY #3
Normally Open or Normally Closed Relay Output
✔
RA #1
Remote Alarm Output
✔
✔
RA #2
Remote Alarm Output
✔
4-20 mA OUT
4-20 mA Signal Output
✔
REC O/P
0-10 VDC Recorder Output
✔
✔
NOTE: Sensors sold separately. Please specify sensor(s) required when ordering.

900 Series Operation Manual – 900OM r03-20
Page 18
B. Sensors
For detailed descriptions of these and other available sensors see the sensor data sheets or contact your
local distributor or the Myron L®Company.
1. Conductivity/Resistivity/TDS/Salinity Sensors
All Myron L®Company 900 Series Conductivity/Resistivity/TDS/Salinity Sensors contain a built-in
precision 1000ΩRTD temperature sensor, mount into a standard ¾” NPT tee fitting, and come with a 10
ft./3 meter shielded cable attached.
a) Conductivity/TDS/Salinity Sensors
The 900 Series Multi-Parameter Monitor/Controller’s Conductivity, TDS, and Salinity use the CS951 or
CS952 Sensors depending on the range and application.
Order Part #
Description
CS951
Conductivity/TDS, ¾” NPT, 0-20,000 μS/ppm, 0.85 cell constant, 10 ft./3 meter cable.
CS951-25
Conductivity/TDS, ¾” NPT, 0-20,000 μS/ppm, 0.85 cell constant, 25 ft./7.6 meter cable.
CS951-100
Conductivity/TDS, ¾” NPT, 0-20,000 μS/ppm, 0.85 cell constant, 100 ft./30.5 meter
cable.
CS951LS
Conductivity/TDS, long style, ¾” NPT, 0-20,000 μS/ppm, 0.85 cell constant, 10 ft./3
meter cable.
CS951LS-25
Conductivity/TDS, long style, ¾” NPT, 0-20,000 μS/ppm, 0.85 cell constant, 25 ft./7.6
meter cable.
CS951LS-100
Conductivity/TDS, long style, ¾” NPT, 0-20,000 μS/ppm, 0.85 cell constant, 100 ft./30.5
meter cable.
CS952
Conductivity/TDS/Salinity, ¾” NPT, >20,000 μS/ppm, 10.0 cell constant, 10 ft./3 meter
cable.
CS952-25
Conductivity/TDS/Salinity, ¾” NPT, >20,000 μS/ppm, 10.0 cell constant, 25 ft./7.6 meter
cable.
CS952-100
Conductivity/TDS/Salinity, ¾” NPT, >20,000 μS/ppm, 10.0 cell constant, 100 ft./30.5
meter cable.
b) Resistivity Sensors
The 900 Series Multi-Parameter Monitor/Controller’s Resistivity uses the CS910 Sensors for use with
ultrapure water applications.
Order Part #
Description
CS910
Resistivity, ¾” NPT, 10 kΩ-20 MΩ, 0.05 cell constant, 10 ft./3 meter cable.
CS910-25
Resistivity, ¾” NPT, 10 kΩ-20 MΩ, 0.05 cell constant, 25 ft./7.6 meter cable.
CS910-100
Resistivity, ¾” NPT, 10 kΩ-20 MΩ, 0.05 cell constant, 100 ft./30.5 meter cable.
CS910LS
Resistivity, long style, ¾” NPT, 10 kΩ-20 MΩ, 0.05 cell constant, 10 ft./3 meter cable.
CS910LS-25
Resistivity, long style, ¾” NPT, 10 kΩ-20 MΩ, 0.05 cell constant, 25 ft./7.6 meter cable.
CS910LS-100
Resistivity, long style, ¾” NPT, 10 kΩ-20 MΩ, 0.05 cell constant, 100 ft./30.5 meter
cable.
c) Conductivity/Resistivity/TDS/Salinity Sensor Cable Extensions
Order Part #
Description
CBL-12395-1
Sensor Cable Extension Kit (cable and connectors),
Conductivity/Resistivity/TDS/Salinity, 25 ft./7.6 meter
CBL-12395-2
Sensor Cable Extension Kit (cable and connectors),
Conductivity/Resistivity/TDS/Salinity, 100 ft./30.5 meter
MCRD-(length)
Conductivity/Resistivity/TDS/Salinity Sensor Cable (cable only), must specify length
(Example: MCRD-300 is 300 ft./91.4 meter)
TBD
Sensor Cable Extension Connector (connectors only),
Conductivity/Resistivity/TDS/Salinity

900 Series Operation Manual – 900OM r03-20
Page 19
2. Pre-amplified pH/ORP Sensors (for use with the 900 Series pH/ORP Input)
All Myron L®Company 900 Series Pre-amplified ½” and ¾” NPT pH and ORP sensors have Ryton®
(PPS) sensor bodies and come with 10 ft./3 meter shielded cables attached. These sensors contain built-
in precision 1000ΩRTD temperature sensors.
a) Pre-Amplified pH Sensors
½”pH Sensors
Order Part#
Description
P92
pH, ½” NPT, bulb tip, Pellon®junction, 10 ft./3 meter cable
¾”pH Sensors
Order Part#
Description
P94
pH, ¾” NPT, bulb tip, Pellon®junction, 10 ft./3 meter cable
P94PE
pH, ¾” NPT, hemi tip, polyethylene (PE) junction, 10 ft./3 meter cable
P94FPE
pH, ¾” NPT, flat tip, polyethylene (PE) junction, 10 ft./3 meter cable
b) Pre-Amplified ORP Sensors
½” ORP Sensors
Order Part#
Description
O92
ORP, ½” NPT, extended tip, Pellon®junction, 10 ft./3 meter cable
¾” ORP Sensors
Order Part#
Description
O94
ORP, ¾” NPT, extended tip, Pellon®junction, 10 ft./3 meter cable
O94PE
ORP, ¾” NPT, extended tip, polyethylene (PE) junction, 10 ft./3 meter cable
O94FPE
ORP, ¾” NPT, flat tip, polyethylene (PE) junction, 10 ft./3 meter cable
c) pH/ORP Sensor Cable Extensions (for use with pre-amplified sensors)
Order Part #
Description
CBL-12396-1
Sensor Cable Extension Kit (cable and connectors), pH/ORP, 25 ft./7.6 meters
CBL-12396-2
Sensor Cable Extension Kit (cable and connectors), pH/ORP, 100 ft./30.5 meters
PHCRD9
pH Sensor Cable (cable only), must specify length
(Example: PHCRD9-300 is 300 ft./91.4 meter)
TBD
Sensor Cable Extension Connectors (connectors only), pH/ORP
3. BNC Style pH/ORP Sensors (for use with the 900 Series mV Input)
All 900 Series BNC Style pH/ORP sensors have Ryton®(PPS) sensor bodies with 10 ft./3 meter shielded
cables attached.
NOTE: BNC Style pH/ORP sensors are not pre-amplified and do not include temperature sensors.
NOTE: The shorting BNC connector cap (included with the 900) must be installed when there is no
sensor connected to the mV Input.
a) BNC Style pH Sensors
½” pH Sensors
Order Part#
Description
P92B
pH, ½” NPT, bulb tip, BNC, Pellon®junction, 10 ft./3 meter cable, plain body
¾” pH Sensors
Order Part#
Description
P94BPE
pH, ¾” NPT, hemi tip, polyethylene (PE) junction, 10 ft./3 meter cable
P94FBPE
pH, ¾” NPT, flat tip, polyethylene (PE) junction, 10 ft./3 meter cable

900 Series Operation Manual – 900OM r03-20
Page 20
b) BNC Style ORP Sensors
½” ORP Sensors
Order Part#
Description
O92B
ORP, ½” NPT, bulb tip, BNC, Pellon®junction,10 ft./3 meter cable, plain body
¾” ORP Sensors
Order Part#
Description
O94BPE
ORP, ¾” NPT, extended tip, polyethylene (PE) junction, 10 ft./3 meter cable
O94FBPE
ORP, ¾” NPT, flat tip, polyethylene (PE) junction, 10 ft./3 meter cable
4. Temperature Sensors
Order Part#
Description
ITS1
Independent Temperature Sensor, ¼” NPT, 0 -120˚C / 32-248˚F, 1000ΩRTD, 3-wire,
25 ft./7.6 meter cable
ITS1-HT
Independent Temperature Sensor, ¼” NPT, High Temperature, 0-185˚C / 32-365˚F,
1000ΩRTD, 3-wire, 25 ft./7.6 meter cable
5. Flow Meter
Order Part#
Description
SPX-075
Flow Meter, ¾”Female NPT, (0.2-20 gpm), Polypropylene, Single Jet, Low Flow
For additional/special order sensors contact your local distributor or the Myron L®Company.