Large MV Motor Diferential Protection 87
Large MV Motor Diferential Protection 87
(OP)
Hi.
There any recommendations or guidelines for knowing when to install the differential protection 87 (87M "motor" or 87S "stator" according to the manufacter) in MV motors, with 1 or 2 set of CT´s for this function, i mean from xxxx KW?
For example from 1500kW? motor up to 1200kW/2000kW?
I am looking for a guide or recommendation of a standard IEC / IEEE / UNE indicate where this information.
A recomendation of GE is (but not show kW values):
h ttp://www. gedigitale nergy.com/ multilin/f amily/moto rs/app_gui de_lm1.htm
Thanks in advance.
Juan Gomez
There any recommendations or guidelines for knowing when to install the differential protection 87 (87M "motor" or 87S "stator" according to the manufacter) in MV motors, with 1 or 2 set of CT´s for this function, i mean from xxxx KW?
For example from 1500kW? motor up to 1200kW/2000kW?
I am looking for a guide or recommendation of a standard IEC / IEEE / UNE indicate where this information.
A recomendation of GE is (but not show kW values):
h
Thanks in advance.
Juan Gomez






RE: Large MV Motor Diferential Protection 87
NO recommendation, no rules, no standarts.
According to local rules only.
I tried found this recommendation few times...
Best Regards.
Slava.
PS, but, if you'll found something, please back with this information
RE: Large MV Motor Diferential Protection 87
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RE: Large MV Motor Diferential Protection 87
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RE: Large MV Motor Diferential Protection 87
But i´m still searching for a GUIDE o SOME PAPERS example IEEE Guide/papers or other international standar.
Maybe we can find a document or study indicating this subjet, if any one knows of have access to a technical information about this, i would be grateful to receive.
VTER, can you send me the web link, to the "ABBs Protective Relaying book"
Thanks in advance.
RE: Large MV Motor Diferential Protection 87
However, many utilities seem to have motor kW based norms for stipulating differential protection for motors.
In PDO, 3.5MW and above require differential protection if they are connected direct to motor MCC. If connected through unit transformers, the motor-unit transformer combination is provided differential protection irrespective of the motor kW rating.
RE: Large MV Motor Diferential Protection 87
regards.