Microhmmeter RMO 100
Microhmmeter RMO 100

- Lightweight - only 7kg
- Powerful 5A - 100A DC
- Measuring range 0 – 999,9mΩ
- Resolution to 0,1μΩ
- SINGLE / CONT Mode
- Mechanical protection IP54
High current DC micro-ohmmeter
Description
RMO100 is a micro-ohmmeter based on state of the art technology, using the most advanced switch mode technique available today. The micro-ohmmeter RMO100 generates true DC current with automatically regulated test ramps. During the test the micro-ohmmeter ramps with increasing current before measuring and decreasing current after the measurement. This eliminates magnetic transients.
After the test current has been set, the automatic test procedure is started by pressing the Ω-button.
The micro-ohmmeter can store up to 500 measurements. All measurements are time and date stamped. Using RMOWin-V2 software a test can be performed from a PC, and the results can be obtained directly at a PC. Using RMOWin-V2 the result can be arranged as an Excel spreadsheet which can be later shown as a diagram and printed for a report.
The set is equipped with thermal and overcurrent protection. The micro-ohmmeter has very high ability to cancel electrostatic and electromagnetic interference in HV electric fields. It is achieved by very efficient filtration. The filtration is made utilizing proprietary hardware and software.
Output Ratings
The full output is available from the micro-ohmmeter at 230V or 115V Mains Supply.
| Supply Voltage | Output Current | Full Load Voltage |
| 230V AC | 100A DC smoothed | 8,0V DC |
| 115V AC | 100A DC smoothed | 8,0V DC |
Output current is filtered and has a ripple of less then 1%. The micro-ohmmeter current output is 100A continuously.
CONT Mode
The micro-ohmmeter can generate DC current continuously using the CONT menu. In this menu the current can be chosen the same way like in the SINGLE menu, but the duration of the test can be preset. The test is started pressing the Ω-button. During the test, a new result is shown on the display and stored into the PC (RMOWin-V2) each second. Using RMOWin-V2 the result can be arranged as an Excel spreadsheet which can be later shown as a diagram and printed for a report.
Application
Typical application is measuring resistance of:
- High, middle and low voltage circuit breakers
- High, middle and low voltage disconnecting switches
- High-current bus bar joints
- Cable splices
- Welding joints
Standard accessories RMO 100
- Current cables 2x5m 16mm2 with battery clips
- Sense cables 2x5m 2,5mm2 with alligator clips
- RMOWin-V2 PC software including RS232 cable
- Mains power cable
- Ground (PE) cable
- Transport bags
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| [Voltage sense cables] | [Current cables] | [Extension cable] |
Optional accessories of RMO 100
- Built-in thermal printer
- Remote control unit
- Current clamp meter
- Transport case
- Test shunt 100μΩ
- Current cables 2x10m 16mm2 with battery clips
- Current cables 2x15m 25mm2 with battery clips
- Extension cable 1x10m 25mm2
- Sense cables 2x10m 2,5mm2 with alligator clips
- Sense cables 2x15m 2,5mm2 with alligator clips
- Sense cables, extension 2x10m 2,5mm2
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| [Transport bags] | [Shunt] | [Transport case] |
Connecting a Test Object to micro-ohmmeter
With the micro-ohmmeter RMO100 turned off, connect the instrument to the test object (Rx) in such a way that the measuring cables from the "Voltage Sense" sockets are attached as close as possible to Rx, and in between the current feeding cables. That way, resistance of both cables and clamps is almost completely excluded from the resistance measurement.
Remote Control Unit
The RMO Remote Control Unit is an optional control unit that is used to start and stop the tests from a remote location, away from the actual RMO. Provided that, for a series of tests, the same test current is fed through the test object, multiple measurements can be carried out with the RMO Remote Control Unit.
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Current clamp meter
Using the micro-ohmmeter RMO100 with current clamp meter it is possible to make safer measurement of breakers with both sides of the breaker grounded. It is performed by measuring the current through the ground connection and reducing this value from the total current.
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Technical data
| 1 Mains Power Supply | |
| - Connection | according to IEC/EN60320-1; UL498, CSA 22.2 |
| - Mains supply | from 90 to 264V AC; 50-60Hz |
| 2 Output data | |
| - Test current | 5A - 100A DC |
| - Measuring range | Resolution |
| 0,1µΩ - 999,9µΩ | 0,1µΩ |
| 1,000mΩ - 9,999mΩ | 1µΩ |
| 10,00mΩ - 99,99mΩ | 10µΩ |
| 100,0mΩ - 999,9mΩ | 0,1mΩ |
| - Typical accuracy | ±(0,25% rdg + 0,25% FS) |
| 3 Environment conditions | |
| - Operating temperature | -10°C - +50°C / 14°F - +122°F |
| - Storage and transportation | -25°C - +70°C / -13°F - +158°F |
| - Humidity | 5% - 95% relative humidity, non condensing |
| 4 Dimensions and Weight | |
| - Dimensions | 198 x 255 x 380mm 7,8 x 10 x 15 in. (A x A x F) without handle |
| - Weight | 7,0kg/15,4 lb |
| 5 Mechanical protection | IP54 |
| 6 Warranty | Two years |
| 7 Safety Standards | |
| - Estándares europeos | EN 61010-1 |
| - European and International standards | IEC 61010-1 UL 3111-1 CAN/CSA-C22.2 No 1010.1-92 |
| 8 Electromagnetic Compatibility (EMC) | |
| - CE conformity | EMC standard 89/336/EEC |
| - Emission | EN 50081-2, EN 61000-3-2/3 |
| - Interference Immunity | EN 50082-2 |













