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The Micro Ohmmeters RMO-A and RMO-G series instruments are designed for contact resistance measurement of non inductive test objects. RMO instruments are based on state of the art technology, using the most advanced switch mode technique available today. RMO generates true DC current with automatically regulated test ramps. During the test RMO ramps with increasing current before measuring and decreasing current after the measurement. This eliminates magnetic transients.
Typical application areas of RMO instruments are high-voltage substations and industrial environments. An important part of commissioning, maintaining and production is measuring the contact resistance of:
  • high, middle and low voltage circuit breakers
  • high, middle and low voltage disconnecting switches
  • high-current busbar joints
  • cable splices
  • welding joints
Contact resistance is a value that is specified as a reference for all kinds of circuit breakers. According to IEC 56 (now IEC62271-100) this resistance value should be measured using a test current between 50 A and the breakers nominal value. According to ANSI C 37.09 the lowest test current is 100 A. Other national and international standards specify similar regulations.
 
Micro Ohmmeters RMO-A series
  RMO100A RMO200A RMO300A RMO400A RMO500A RMO600A
CURRENT RANGE 2 A-100 A 2 A-200 A 2 A-300 A 2 A-400 A 2 A-500 A 2 A-600 A
RESISTANCE RANGE 0,1 µΩ - 999,9 mΩ 0,1 µΩ - 999,9 mΩ 0,1 µΩ - 999,9 mΩ 0,1 µΩ - 999,9 mΩ 0,1 µΩ - 999,9 mΩ 0,1 µΩ - 999,9 mΩ
RESOLUTION 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ
ACCURACY 0,25 % 0,25 % 0,25 % 0,25 % 0,25 % 0,25 %
SINGLE TEST YES YES YES YES YES YES
CONTINUOUS TEST YES YES YES YES YES YES
PC SOFTWARE YES YES YES YES YES YES
REMOTE CONTROL UNIT NO NO NO NO NO NO
BOTH SIDES GROUNDED UNIT NO NO NO NO NO NO
BUILT-IN THERMAL PRINTER OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
 
Micro Ohmmeters RMO-G series
  RMO100G RMO200G RMO300G RMO400G RMO500G RMO600G RMO800G
CURRENT RANGE 2 A-100 A 2 A-200 A 2 A-300 A 2 A-400 A 2 A-500 A 2 A-600 A 2 A-800 A
RESISTANCE RANGE 0,1µΩ - 999,9mΩ 0,1µΩ - 999,9mΩ 0,1µΩ - 999,9mΩ 0,1µΩ - 999,9mΩ 0,1µΩ - 999,9mΩ 0,1µΩ - 999,9mΩ 0,1µΩ - 500,0mΩ
RESOLUTION 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ 0,1 µΩ
ACCURACY 0,2 % 0,2 % 0,2 % 0,2 % 0,2 % 0,2 % 0,2 %
SINGLE TEST YES YES YES YES YES YES YES
CONTINUOUS TEST YES YES YES YES YES YES YES
PC SOFTWARE YES YES YES YES YES YES YES
REMOTE CONTROL UNIT OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
BOTH SIDES GROUNDED UNIT OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
BUILT-IN THERMAL PRINTER OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
Accessories
Cables and clamps

IBEKO provides Current Cables with cross sections from 16 mm2 to 95 mm2 (16, 25, 35, 50, 70 and 95 mm2), with lengths of 3, 5, 10 and 15 m. All our Current Cables can be delivered with the following types of clamps: Standard clamps, C clamps, isolated clamps, non-colored clamps and semi-isolated clamps.
Sense Cables are 2,5 mm2 cross section with lengths of 3, 5, 10 and 15 m.
Extension Cables are with cross sections from 16 mm2 to 70 mm2 and with lengths of 5 m and 10 m.


 
 
 
Remote Control Unit
The RMO Remote Control Unit is an optional control unit, for RMO-G series instruments, that is used to start and stop the tests from a remote location, away from the actual RMO.
Very often the same test current is fed through the test object for a series of tests. To simplify this and speed up the process, multiple measurements can be carried out with the RMO Remote Control Unit.
  
Transport Bags, Transport Case
We offer transport bags (device bag and cable bag) as a standard accessories.
Also, we offer hard transport case as an optional accessory which improves mechanical protection of devices in transport.
  
Both Sides Grounded Unit
Using Micro Ohmmeters RMO-G series with current clamp it is possible to make safer measurement of an HV circuit breaker resistance with both sides of the breaker grounded. It is performed automatically by measuring the current through the ground connection and reducing this value from the total current. This is an optional accessory.
Test shunt
IBEKO provides as optional test shunts 600 A/60 mV and 1000 A/100 mV. It could be used for accuracy checking of our Micro Ohmmeters.
Built-in thermal printer
We deliver devices with 80 mm paper wide built-in thermal printer, as an optional accessory.

Calibration Set for Micro Ohmmeter Series RMO
With our Calibration Set for Micro Ohmmeters you can calibrate devices with USB and RS232 interface.
Standard accessories
  • Digital Multimeter
  • DV Power Switch Box
  • Test Shunts
  • Voltage Sense cables
  • RMOWin-CAL Software
We provide three Test Shunts and DV Power Switch Box, calibrated in SP National Testing and Research Institute, Borås, SWEDEN. Test shunts and Digital Multimeter are calibrated at manufacturers facilities.
 
RMO60E
We are producing Micro Ohmmeter for Protective Earth Resistance Measurement RMO60E.
For more information click here

IBEKO POWER AB, Box 1346, 181 25 Lidingö, Sweden, Tel +46 8 731 76 99, Fax +46 8 731 77 99