insulation resistance test with connections on the relay

[comuniti]

Dear all.
I have few doubts regarding Insulation resistance testing...
- if we do IR test on current or voltage circuit which is completely connected (meaning CT/VT connections are done from the CT/VT and all up to the analog inputs of the protection relay) and if we do IR test with 500 V, is it dangerous for the analog inputs of the relay? Can it damage analog inputs? For example for ABB RED670 or Siemens 6MD86 relays
- if we do IR test on wire connection which are connected to the binary inputs or binary outputs of the protection relays with 500V, is it going to damage binay inputs/outputs?
- how can I find data for maximum allowed voltage for IR test for relays.
- should I disconnect all wires from relays before making IR test (for safety reasons)?
Thanks all

 

[DTR2011]

We have a substation around here where there
Are signs everywhere not to megger the meter/transducers. They are older units in series with the EM relays.

We megger SEL relay VT/CT circuits all the time as part of commissioning and routine maintenance of the IT circuits.

 

[PSEng01]

We accidentally IR'ed 2kV on SEL with all analogue and binary connected, voltage stayed on.


... But please don't do it again, like seriously.