Hi everybody,

on a BFW pump we adjusted the gap voltage on an axial position for -9.75 VDc as per BN spec. but the problem is when the motor starts the shaft will shift momently by 0.4 mm beyond the trip s.p., after few seconds the shaft will go back to normal position.

does anybody knows if there a configuration on BN where this trip can be avoided when starting the motor, maybe by increasing the gap voltage in order to inhibit this trip when starting the motor.

Thanks,
Hamad

 

Hamad,

What do you mean by BN? Does it mean Bently Nevada vibration monitoring system?

If it is Bently, what is the model of your system?

Normally there is capability to inhibit the trip/Shutdown signal, even you can set a specified time to pass from critical condition during start up.

 

Leave gap alone. If you have a 3500 rack, get the config software from your Bently Service location.

enable the trip multiplier for that channel.

Maybe get a Bently service rep to help you. GE owns them.

What this does is temporally increase your trip setpoint (during a start, for instance).

Good Luck