grounding medium voltage motors
grounding medium voltage motors
(OP)
Hi all,
I have two underflow pumps (552 kW each, 4.16 kV) for the thickeners in a mining project. For this size of motors I normally use a two 2/0 AWG bare copper cable to ground the motor directly to the earthing grid. In this case we dont have a grouding grid under the motors because of possible leaks from the tanks. Civil enginering doesnt want any perforation on the underflow tunnels. So the solution to ground the motors is to run a 2/0 awg bare copper cables on a cable ladder to the grounding grid which is outside of the tunnel.
Is this correct? My understanding is that we ground the motors locally to have an equipotencial bonding between all metal structures in the area. Also in case there is a electrical fault on the motor, and someone is standing next to it, we can control the mesh and step voltages that person will be subject to.
Please I want some comments on the design. Attached a file with the propose solution.
Regards,
cmed
I have two underflow pumps (552 kW each, 4.16 kV) for the thickeners in a mining project. For this size of motors I normally use a two 2/0 AWG bare copper cable to ground the motor directly to the earthing grid. In this case we dont have a grouding grid under the motors because of possible leaks from the tanks. Civil enginering doesnt want any perforation on the underflow tunnels. So the solution to ground the motors is to run a 2/0 awg bare copper cables on a cable ladder to the grounding grid which is outside of the tunnel.
Is this correct? My understanding is that we ground the motors locally to have an equipotencial bonding between all metal structures in the area. Also in case there is a electrical fault on the motor, and someone is standing next to it, we can control the mesh and step voltages that person will be subject to.
Please I want some comments on the design. Attached a file with the propose solution.
Regards,
cmed





RE: grounding medium voltage motors
RE: grounding medium voltage motors
regards
RE: grounding medium voltage motors
This is similar to the mats installed below manually operated high voltage distribution switches to provide protection for the line-men operating the switch handle.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: grounding medium voltage motors
I understand the purpose of the mesh platform next to the motor, but why you dont recommend connecting the mesh to the ground grid and from the mesh to the motor?
regards
RE: grounding medium voltage motors
Bill
--------------------
"Why not the best?"
Jimmy Carter