RMO400 is a micro-ohmmeter based on state of the art technology, using the most advanced switch mode technique available today. RMO400 generates true DC current with automatically regulated test ramps. During the test RMO400 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 test result is displayed as R=U/I. There is enough memory in RMO400 to store 100 measurements. All measurements are time and date stamped. They can also be exported to a PC with RMO-Win software. The software connects a PC to RMO400 using a RS232 cable. The RMO-Win makes it easy to report and analyse all results.
RMO400 has very high ability to cancel electrostatic and electromagnetic interference in high HV electric fields. It is achieved by very efficient filtration. The filtration is made utilizing appropriate hardware and software.
Output Ratings
The full output is available from the RMO400 for a 230V+10%-15% supply. A reduced output is available from lower supply voltages.
Supply Voltage Output Current Full Load Voltage
230 V AC 400 A DC 5,0 V DC 300 A DC 5,5 V DC 115 V AC 400 A DC 3,3 V DC 300 A DC 4,0 V DC
Output current is filtered and has a ripple of less then 1%.
The RMO400 output is rated at 300 A for 2 minutes and 200 A continuously at 25°C ambient.
CONT Mode
RMO400 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) each second. Using RMOWin the result can be printed like an Excel table which later can be shown as a diagram and used for a report.
Typical application is measuring resistance of:
high, middle and low voltage circuit breakers
high, middle and low voltage disconnecting switches