Outside contractors

[puckman]

We have a heating and ac contractor planning on doing work at our plant on our hot water heating system. We have a system not working now that have VFD'S controlling the blower motors [25hp] . The VFD'S were sq. d Omegerpak mounted on the doors of the buckets in the mcc. Their plan is to mount the new VFD to the old VFD'S. I told the contractor that wasn't the right way to go , and he should also atleast add a overload relay for the motor.
His response was it didn't have one so he doesn't have to put one in.
My question is does anyone run into this type of situations and how do you handle them?

I am fairly new employee and the contractor has been there for 8 years so he has a close working relation with powers in charge.

 

[ptonsparky]

He is replacing the old VFD with a new one?

Drives have all the overcurrent protection you need for the motors if someone takes the time to adjust the parameters. As long as the SC protection, etc ahead of the new drive is met with the existing equipment, I say he is good.

 

[boboelectric]

Don't worry about it until it is your problem in a year's time.