Obsolete Test & Measurement Products


626000433 (OBSOLETE)


Combination tester

The Combination Tester CMB-S or Combi Compact is one of the most compact portable combitesters available. The instrument is designed especially for installers or maintenance people who frequently need to check or inspect LV-installations after modification, initial inspection or addition. The tester can inspect, measure and test different kinds of RCD’s (normal and selective), net or loop impedance and (insulation) resistance on LV-installations, according the EN 61557 regulation. Voltage and frequency can also be measured by the CMB-S.

Following tests

  • RCD-test
    • Contact voltage Uc at a current of 1/2 IΔN or 2 IΔN (selective type), without tripping the RCD
    • Trip current IΔ
    • Trip time (t) at a current of 1/2 IΔN, IΔN, 2 IΔN, 5 IΔN
    • Autotest (for type qualification)
  • LOOP (L-PE) / Line impedance (L-N)
    • Loop impedance
    • Line impedance
    • Short-circuit current Ipsc
    • Check on earth potential (safe or dangerous)
    • RS-Loop resistance without tripping RCD
  • Insulation test 500V
  • Resistance (R)
  • Voltage (V)
  • Frequency (F)
The CMB-S has an internal memory of 1500 locations for storing the measured values. These stored values can easily be transferred to a PC via the InfraRed (IrDa) port.


  • Network test lead
  • Split test lead
  • Test probes
  • Alligator clamps
  • Protective holster
  • Manual

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