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cts_casemod · 12-25-2014, 01:58 PM

The other day I was thinking about system isolation.

Normally one does away with linking the HV and LV grounds for Isolation purposes, but that got me thinking what would happen if a fault on the motor windings does occur.

The motor is earthed to the chassis, so the chassis will become live. The isolation means a standard RCD cannot be used to detect the fault.

The other thing is capacitive coupling. There may be a difference of potential of a few KV due to static charge accumulation that may blow the isolators or other devices that have linkage between the power rails.

Has anyone considered this?

12-25-2014, 01:58 PM	#1488 (permalink)
cts_casemod EcoModding Apprentice Join Date: Nov 2012 Location: East Midlands Posts: 180 Thanks: 13 Thanked 81 Times in 52 Posts	The other day I was thinking about system isolation. Normally one does away with linking the HV and LV grounds for Isolation purposes, but that got me thinking what would happen if a fault on the motor windings does occur. The motor is earthed to the chassis, so the chassis will become live. The isolation means a standard RCD cannot be used to detect the fault. The other thing is capacitive coupling. There may be a difference of potential of a few KV due to static charge accumulation that may blow the isolators or other devices that have linkage between the power rails. Has anyone considered this? Last edited by cts_casemod; 12-26-2014 at 04:57 PM..