When operating direct current railways with return lines via running rails, different grounding resistances create voltages that can be dangerous for people and buildings. The earth potential measuring device WITT EPM 4 measures the potentials of the connected earths or railway earths and evaluates the voltages that occur.
This measuring device monitors the potentials of the connected earths or railway earths and evaluates the voltages that occur (see technical data). The device does not require any auxiliary voltage, the supply is made from the input voltage to be monitored.
The voltage between the earths to be monitored or the return line is measured continuously.
If the limit values are exceeded, a switching command is given via a potential-free relay contact to control additional equipment – earthing short-circuiters or disconnectors.
Two potential-free changeover contacts are available for the message.
|Dielectric strength is||2000 VDC / 1400 VAC|
|Threshold 1||& gt; 115 V|
|Threshold 2||& gt; 85 V|
|Measurement tolerance typically||10%|
|Auxiliary voltage range||60 VDC – 200 VDC|
When ordering, you can specify your individual TARGET values. We usually manufacture and test these for you at no additional cost: