Q:How to determine the GracePESD Test point Voltage readings?

A.) GracePESD devices have varying resistance across test points, causing voltage reduction.

The R-3MT = 102kΩ per point

The R-3MT-VI (ChekVolt) = 164kΩ per point

The following formula can be used to find the expected voltage, for accuracy we recommened 10MOhm Multimeter.

(Meter Resistance / Sum Test point Resistance) x System Voltage = Calculated Reduction Voltage(Expected Meter reading)

Example "R-3MT":

(1MΩ / (102kΩ + 102kΩ)) x 480V = 398V

For a more in depth explanation please see our Safe-Test Point High Impedance Technical Note here.

If you require further assistance please contact the Sales Department at Sales@gracetechnologies.com