Orbit Merret OM 351 User manual

OM 351
3 1/2 DIGIT PROGRAMMABLE
DC VOLTMETER/AMMETER
AC VOLTMETER/AMMETER
PROCESS MONITOR
OHMMETER
THERMOMETER FOR PT 100/500/1 000
THERMOMETER FOR NI 1 000
THERMOMETER FOR THERMOCOUPLES
DISPLAY INST. FOR LINEAR POTENTIOMETERS
GUARANTEE
YERS

2|INSTRUCTIONS FOR USE OM 351
SAFETY INSTRUCTIONS
Please, read the enclosed safety instructions carefully and observe them!
These instruments should be safeguarded by isolated or common fuses (breakers)!
For safety information the EN 61 010-1 + A2 standard must be observed.
This instrument is not explosion-safe!
TECHNICAL DATA
Measuring instruments of the OM 351 series conform to the European regulation 89/336/EWG
and the Ordinance 168/1997 Coll.
They are up to the following European standards:
EN 55 022, class B
EN 61000-4-2, -4, -5, -6, -8, -9, -10, -11
The instruments are applicable for unlimited use in agricultural and industrial areas.
CONNECTION
Supply of energy from the main line has to be isolated from the measuring leads.
ORBIT MERRET, spol. s r.o.
Vodňanská 675/30
198 00 Prague 9
Czech Republic
Tel: +420 - 281 040 200
Fax: +420 - 281 040 299
e-mail: [email protected]
www.orbit.merret.cz

INSTRUCTIONS FOR USE OM 351 |3
1. Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Instrument description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4. Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Symbols used in the instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Setting the DP and the (-) sign . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Control keys functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Configuration of user menu items. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
5. Setting “LIGHT” menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.0 Description “LIGHT” menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Setting input type “DC”. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Setting input type “AC” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Setting input type “PM”. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Setting input type “DU”. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Setting input type “OHM”. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Setting input type “RTD” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Setting input type “T/C” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Setting the limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Setting the analog output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Setting the menu type (LIGHT/PROFI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Restoration of the manufacture setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Calibration of the input range (DU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Setting new access password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Instrument identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6. Setting “PROFI” menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
6.0 Description “PROFI” menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
6.1 “PROFI” menu - INPUT
6.1.1 Tare reseting 38
6.1.2 Setting the measuring range, displacement, compensation and measuring rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
6.1.3 Setting the external control input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
6.1.4 Setting functions of the control key (ENTER) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6.2 “PROFI” menu - CHANNELS
6.2.1 Projection on the display (MIN, MAX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
6.2.2 Setting the digital filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
6.2.3 Setting the decimal point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
6.3 “PROFI” menu - OUTPUT
6.3.1 Cofiguration and setting the limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
6.3.2 Setting the data output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
6.3.3 Setting the analog output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
6.3.4 Setting the display brightness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
6.4 “PROFI” menu - SERVICE
6.4.1 Selection of the type of programming menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
6.4.2 Restoration of the manufacture setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
6.4.3 Calibration of the input range (DU). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
6.4.4 Setting new access password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
6.4.5 Instrument identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
7. Setting “USER” menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
7.0 Configuration “USER” menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
8. Method of measuring of the cold junction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
9. Data protocol 57
10. Error statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
11. Technical data60
12. Instrument dimensions and installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
13. Certificate of guarantee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
1CONTENTS

4|INSTRUCTIONS FOR USE OM 351
2.1 description
The OM 351 model series are 3 1/2 digit programmable panel instruments, manufactured in the following alternatives:
OM 351DC DC voltmeter/ammeter
OM 351AC AC voltmeter/ammeter
OM 351PM Process monitor
LÁDÁN
OM 351RTD Thermometer for Pt 100/500/1 000, Ni 1 000
OM 351T/C Thermometer for thermocouples
OM 351DU Display instrument for linear potentiometers
OM 351OHM Ohmmeter
The instruments are based on an 8-bit microcontroller with A/D converter, which secures high accuracy, stability and easy
operation of the instrument.
Programmable projection of the display
Setting selection of measuring range
Calibration projection for both limit values of the input signal
Projection ±1999
Linearisation
Linearisation through linear interpolation in 25 points (only for OM Link)**
Compensation of
Conduct automatic compensation of 2-wire conduct
Probes compensation of internal resistance of the measuring probe
(conduct resistance in the measuring head)
Cold junctions fixed or automatic
Digital filters
Rounding setting the projection step for display
Exponen. average from 2…100 measurements
Mathematic functions
Tare* assigned to reset display in case of non-zero input signal
External control
Hold display/instrument blocking
Lock locking the control keys for access into Configuration menu
Tára* tare activation
* only for types DC, PM, DU **only for types DC, PM, OHM, DU
INSTRUMENT DESCRIPTON2

INSTRUCTIONS FOR USE OM 351 |5
2.2 Operationn
The instrument is set and controlled by five control keys located on the front panel. All programmable settings of the instru-
ment are realized in two adjusting modes:
LIGHT Simple programming menu
- contains only items necessary for instrument setting and is protected by an optional numeral code
PROFI Complete programming menu
- contains complete instrument menu and is protected by an optional numeral code
USER User programmable menu
- may contain arbitrary items selected from programmable menu (LIGHT/PROFI), which determines the
authorization (see or change)
- access is without password
All programmable parameters are stored in the EEPROM memory (they hold even after the instrument is switched off).
Complete operation and setting of the instrument may be performed via communication interface
OM Link, which is a standard equipment of every instrument.
The operation program is freely available (www.orbit.merret.cz) and the only requirement is the
purchase of OML cable for connecting the instrument to PC. It is manufactured in version RS 232 and USB and is compatible
with all ORBIT MERRET instruments.
Another option for connection is with the aid of data output RS 232 or RS 485 (without the need for OML cable).
The OM LINK program version „Standard“ allows you to connect an unlimited number of instruments with the option of
visualizatiion and storage in PC.
2.3 Extension
Excitation is suitable for feeding sensors and converters. It has a galvanic isolation.
Comparators are assigned to control two limit values with relay output. The limits have adjustable hysteresis as well as
selectable delay of the switch-on. Reaching the preset limits is signalled by LED and simultaneously by the switch-on of the
relevant relay.
Data outputs are for their rate and accuracy suitable for transmission of measured data for further projection or directly
into the control systems. We offer an isolated RS232 and RS485 with the ASCII protocol.
Analog outputs will find their place in applications where further evaluating or processing of measured data in external
devices is required. We offer a universal analog output with the option of selection of output type - voltage/current. The value
of analog output corresponds with the displayed data and its type and range are selectable in the programming mode.
2INSTRUMENT DESCRIPTON

6|INSTRUCTIONS FOR USE OM 351
The lead for feeding of the instrument should not be in the proximity of incoming low-potential signals.
Contactors, motors with larger input power and other efficient elements should not be in the proximity of the instrument.
The lead into instrument input (the measured quantity) should be in sufficient distance from all power leads and appliances.
Provided this cannot be secured, it is necessary to use shielded leads with connection to ground (terminal E).
The instruments are tested in compliance with standards for use in industrial area, yet we recommend to abide by the above
mentioned principles.
S+
E- S- E+
S-
ES+ES-
ES+E-
12 3
-
E N
L
+
POWER SUPPLY
TxD
GND
RxD
Rx/Tx- Rx/Tx+ GND
232
232
485
485
8910
Hold/Lock
INPUT
-
+
GND
14 15 1611 12 13
CJC
Hold/Lock
OM 351T/C
OM 351RTD, OHM
L2
L1
4567
Analog output - I
+
GND
Analog output - U
-
+
INSTRUMENT CONNECTION3
Grounding on terminal „E“ has to be connected
at all times.
In case of RTD and OHM inputs with 2- or 3- wire
connection it is necessary to link the unconnected
inputs on the terminal board (13+14/15+16 or
15+16).
!

INSTRUCTIONS FOR USE OM 351 |7
Analog output - I
+
GND
Analog output - U
-
+
12 3
-
E N
L
+
POWER SUPPLY
TxD
GND
RxD
Rx/Tx- Rx/Tx+ GND
232
232
485
485
8910 14 15 1611 12 13
Hold/Lock/Tare
BE
Hold/Lock/Tare
INPUT 2 INPUT 1
-
+
+
INPUT 3
+
GND
OM 351DC, PM
OM 351DU
L2
L1
4567
Excitation
-
+
Hold/Lock
INPUT 1 INPUT 3
GND
OM 351AC
INPUT 2
MEASURING RANGES
Type/Input Input 1 Input 2 Input 3
OM 351 AC 0…60/150/300 mV 0…10 V 0…120 V
OM 351 AC 0…1 (2,5)/5 A 0…250 V 0…450 V
OM 351 DC ±2/±20 mA ±0,2/±2 V ±20/±200 V
OM 351 DC 0…1/5 A 0…60/150 mV
OM 351 PM 0/4…20 mA 0…2 V 0…5/10 V
OM 351 OHM 0…200 Ohm * 0...2 kOhm * 0...100 kOhm * 5…105 Ohm
3INSTRUMENT CONNECTION

8|INSTRUCTIONS FOR USE OM 351
For trained users
Only items necessary for instrument
setting
Password protected access
Possibility to arrange items of the
„User“ menu
•
•
•
•
For expert users
Complete instrument menu
Access is password protected
Possibility to arrange items of the
„User“ menu
•
•
•
•
SETTING PROFISETTING LIGHT
For user operation
Menu items are set by the user
(Profi/Light) as per request
Access is not password protected
Optional menu structure either tree
(PROFI) or linear (LIGHT)
•
•
•
•
SETTING USER
INSTRUMENT SETTING4

INSTRUCTIONS FOR USE OM 351 |9
4INSTRUMENT SETTING
4.1 Description
The instrument is set and controlled by means of five control keys located on the front panel. All programmable settings of the
instrument are realised in three adjusting modes:
LIGHT Simple programming menu
- contains only items necessary for instrument setting and is protected by an optional numeral code
PROFI Complete programming menu
- contains complete instrument menu and is protected by an optional numeral code
USER User programmable menu
- may contain arbitrary items selected from programmable menu (LIGHT/PROFI), which determines the
authorization (see or change)
- access is without password
Complete operation and setting of the instrument may be performed via communication interface OM Link, which is a
standard equipment of every instrument.
The operation program is freely available (www.orbit.merret.cz) and the only requirement is the purchase of OML cable for
connecting the instrument to PC. It is manufactured in version RS 232 and USB and is compatible with all ORBIT MERRET
instruments.
Another option for connection is with the aid of data output RS 232 or RS 485
(without the need for OML cable).

10 |INSTRUCTIONS FOR USE OM 351
Setting and controlling th instrument is performed by means of 5 control keys located on the front panel. With the aid of these
keys it is possble to browse through the operation menu and to select and set required values.
SYMBOLS USED IN THE INSTRUCTIONS
DC AC PM
DU OHM RTD
T/C
Indicates the setting for given type of instrument
DEF values preset from manufacture
42symbol indicates a flashing light (symbol)
MI N inverted triangle indicates the item that can be located into USER menu
after pressing the key the set value will not be stored
after pressing the key the set value will be stored
30
continues on page 30
SETTING THE DECIMAL POINT AND THE MINUS SIGN
DECIMAL POINT
Its selection in the menu, upon modification of the number to be adjusted it is performed by the control key with transition
to beyond the highest decade, when the decimal point starts flashing . Positioning is performed by /.
THE MINUS SIGN
Setting the minus sign is performed by the key on higher decade. When editing the item substraction must be made from
the current number (e.g..: 013 > , on class 100 > -87)
1T2M
143.7
Relay status
ON the digit is lit
OFF the digit is not lit
OFF the digit is flashing
limits with restriction
(delay)
Function
T Tare
Measured value
INSTRUMENT SETTING4