All,
Thank you everyone who has participated in this thread.
I have learned so much through this process and all of your feedback!
We have been able to find the root cause of this issue and get the items resolved.
First, we found that one of the SCR's was letting through current and...
jraef,
One more comment on the voltage issue in regards to the SMC circuit.
We have our own on site power generation turbines and we supplement power from Consumers Energy.
This issue is off one branch of the Power House and none of our other substation equipment is having this issue. As far...
jraef,
I completely again on both accounts. The waveform is something very abnormal. We have several 3rd parties trying to identify this issue.
I also agree that the bypass should be straight line power but at this point we are open to any possibility. We just completed a pump study from...
We have a power quality analyzer connected to the Load side of the SMC and it has been recording data for about 3 weeks.
We have not seen any voltage issues such as described that correspond with the pulsations of the motor.
I am attaching a snapshot of the voltage readings that shows all...
FacEngPE,
The SMC portion of this system was upgraded in 2015 so it's newer.
We do run in bypass once the motor is up to speed. This soft start has two large vacuum contactors. With starting and running coils for each.
Once the motor starts the Bypass contactor closes putting the system on full...
waross,
Thank you for the detailed response.
We are currently looking into the impeller as it was changed and the size increased by the OEM to increase flow. During our next outage we are planning to return the impeller to the previous size.
There were no other changes to the system during...
All,
We have 400A medium voltage (2,300V) SMC-Flex soft starter on a 330 A Motor.
About 1 year ago we noticed a significant pulsating at a consistent frequency (approx. once per second)... never faster or slower only louder or softer.
When the load is removed and the motor is uncoupled the...
