GE 239 Motor Protection Relay RTD Alarm

Could u be more specific? Pl mention motor rating, Voltage.You are mentioning RTD and then next line thermistor .Both are different though both are used for protecting the motor against overheating.

The motor is reted at 410kw , 3.3kv (3 set of RTD MOTOR WINDING) and protect by GE 239 motor protection relay.

Best Regards

Chan KK

The motor is reted at 410kw , 3.3kv (3 set of RTD MOTOR WINDING) ABB motor and protect by GE 239 motor protection relay.

Best Regards

Chan KK

This is nothing to do with motor ratings, and voltage.It is purely setting on the relay to bypass the alarm event.

Best would be go through the manual of GE motor protection relay or the service Engineer of GE who is familiar with these relays.

Dear Ramvinod

Thank for fit back and I have ratify the problem was the underground cable connect between the protection relay & motor RTD having high resistance. Temporary lay cable on surface :

1, Put the HT switchgear at test position, apply 120Vac test supply.

2. Remove the RTD & connect up the resistance bank to the temporary cable, increases & decreases the resistance the switchgear was trip at high resistance.

3. Connect back the RTD and test run the motor & return to service

Best Regards

chan KK

Um, didn't anyone else see the problem as I do?

Unless there is a semantics issue here, you are apparently attempting to install a Thermistor in the motor to an RTD input on the relay. They are two different things. The 239 has, as standard, a separate Thermistor input on terminals 21 and 22. If you are using a motor thermistor, that is where you must connect it.

If you ordered the RTD option and do NOT install any RTDs, you must first slap yourself silly for wasting money, then go in to programming and disable all of the RTD inputs, otherwise it will trip on failed RTD.

Hey, isn't that what you are getting!?

Great ! Experience speaks !

Dear JRaef :

The ABB motor is come with 3 set of RTD connection ,is provide addition protection for the motor insulation breakdown of the stator winding due to overheating failure.

The the GE 239 motor protection relay also design for the RTD input connection from terminal T49 to T57 ,no need to install addition Thermistor for the motor overheating protection is wasting money.

Best Regards

Chan Kum Kong

I know what motor RTDs are for and I know how a 239 works for crying out loud. I was trying to help.

Quoted from your original post...

"Motor stator winding thermistor is normal and operating temperature is in between the insulation class"

That said to me that you have a thermistor, not RTDs. Now you say they are RTDs, not a thermistor. Make up your mind.

If you make erroneous statements, you get the answers you deserve.