Earth fault loop impedance readings through a UPS supply

[treak]

Does anyone have any experience in recording values of EFLI on circuits fed through a DB supplied via a UPS please? The meter shows the above scale arrow.
I understand that there will be no reference to the external earth due to the inverter inside the UPS but what will happen to the UPS supplied circuits under fault conditions in normal supply mode? Is this something to be taken up with the manufacturer? Then there is next question how does the UPS deal with a fault in power failure mode? Not to worried about the second part, I obviously need to take some readings of EFLI to record and to see if they are sufficent to meet disonnection times.
Any help would be great.

 

[IQ Electrical]

You are only measuring the impedance of the output stage of the UPS.

Record values on bypass and remember that the UPS itself will clear any faults by limiting it's own short circuit current and eventually shutting down-often at around 100mS to protect the inverter and any damage downstream caused by the fault.