Orbit Merret OMM 37 User manual

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OMM 37
3 1/2 DIGIT
DC VOLTMETER/AMMETER
PROCESS MONITOR
THERMOMETER FOR PT 100

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INSTRUCTIONS FOR USE OMM 37
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 OMM 37 series conform to the European regulation 89/336/EWG and the Ordinance
168/1997 Coll.
They are up to the following European and Czech 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.
Vodnanska 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

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1. CONTENTS
1. Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Instrument description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Setting the decimal point. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Change of projection on the display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5. Technical data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6. Instrument dimensions and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
7. Certificate of guarantee. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1. CONTENTS

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INSTRUCTIONS FOR USE OMM 37
2. INSTRUMENT DESCRIPTION
DESCRIPTION
The OMM 37 model series include simple 3 1/2 digit panel instruments in these alternatives:
DC DC voltmeter/ammeter
PM Process monitor
RTD Thermometer for Pt 100 sensors
For their dimensions the instruments are suitable for mosaic panel installation.
ADJUSTABLE DISPLAY PROJECTION
Setting by potentiometers from the back of the instrument (in the range of approx. ±10 %)
Projection ±1999
OPERATION
The instrument is designed for simple measurement without further control.
Placement of the decimal point is selectable by a jumper under the front panel.
EXTENSION
Isolated supply of the instrument with range of 7...30 VDC is designated for applications where galvanic
separation must be used.

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3. CONNECTION
3. CONNECTION
The lead for feeding the instrument should not be in the proximity of the incoming low-potential signals.
Contactors, motors with larger input power and other efficient elements should not be in the proximity of the instru-
ment.
The lead into the input of the instrument (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.
The instruments are tested in compliance with standards for use in industrial area, yet we recommend to abide by
the above mentioned principles.
+ +
- -
1234
INPUT
POWER SUPPLY
ES-ES+
+
-
1234
POWER SUPPLY
OMM 37DC, PM
OMM 37RTD

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INSTRUCTIONS FOR USE OMM 37
4. INSTRUMENT SETTING
SETTING BRIGHTNESS AND DECIMAL POINT
After removing the top cover frame the following settings are accessible
Decimal point
by jumper X1
Display brightness
by trimmer P1 under the front
panel
MODIFICATION FO THE MEASURING RANGE
The adjusting trimmers for correction of display projection
are accessible at the input brackets of the instrument
Full range
- setting display projection (approx. ±10 %)
Offset
- shifting zero
- (compensation of 2-wire lead for OMM 37RTD),
- the trimmer is fitted only in the OMM 37PM and RTD
model
Brightness regulation
Offset
Full range
FO
1 - 2 X.xxx
3 - 4 XX.xx
4 - 5 XXX.
x
Jumper X1
1
5
X1
P1

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4. INSTRUMENT SETTING

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INSTRUCTIONS FOR USE OMM 37
INPUT
the range is fixed, according to order DC
±199,9 mV 1 MOhm
±1,999 V 1 MOhm
±19,99 V 1 MOhm
±199,9 V 1 MOhm
±199,9 µA < 260 mV
±1,999 mA < 260 mV
±19,99 mA < 260 mV
±199,9 mA < 260 mV
the range is fixed, according to order PM
0...5 mA < 260 mV
0...20 mA < 260 mV
4...20 mA < 260 mV
±2 V 1 MOhm
±5 V 1 MOhm
±10 V 1 MOhm
RTD
Pt 100 -20°...140°C
Type Pt: 100 Ohm, platinum element,
s α=0,00385Ohm/Ohm/°C
Connection: 2 wire
PROJECTION
Display: ±1999, intensive red or green LED,
digit height 9,1 mm
Decimal point: adjustable - by jumper
Brightness: adjustable - by trimmer inside the instrument
INSTRUMENT ACCURACY
TC: 100 ppm/°C
Accuracy: ±0,1 % of range
±0,8 % of range RTD
Resolution: 1°C RTD
Rate: 2,5 measurements/s
Overload: 10x (t < 100 ms), 2x (long-term)
Calibration: at 23°C and 40 % r.h.
POWER SUPPLY
7...12 V AC/DC, max. 100 mA (DC), 60 mA (AC)
7...30 V AC/DC, max. 160 mA (DC), 280 mA (AC),
(24 VDC/55 mA), isolated
MECHANIC PROPERTIES
Connection: connector terminal board
conductor cross section up to 2,5 mm2
Material: Noryl GFN2 SE1, incombustible UL 94 V-I
Dimensions: 48 x 24 x 75 mm
Panel Cut-out: 43,5 x 22,5 mm
OPERATING CONDITIONS
Stabilization period: within 15 minutes after switch-on
Working temp.: 0°...50°C
Storage temp.: -10°...85°C
Cover: IP42, (front panel only)
Overvoltage cat.: EN 61010-1, A2
III. - instrument power supply (300 V)
II. - input (300 V)
for pollution degree II
EMC: EN 61000-3-2+A12; EN 61000-4-2, 3, 4, 5, 8, 11;
EN 550222, A1, A2
5. TECHNICAL DATA

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5. TECHNICAL DATA

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INSTRUCTIONS FOR USE OMM 37
6. INSTRUMENT DIMENSIONS
Panel cut
Side view
Front view
43,5 mm
22,5 mm
48 mm
24 mm
5 mm
72 mm
Panel thickness: 0,5...20 mm