14-06-2020, 07:39 AM
In fact a DC belt from HT is thought to be more dangerous than AC mains.
You are more likely to have reflex action on AC to react and come off than DC. My 1.5kv isolating transformer would occasionally blow a 10 Amp plug fuse but is OK with a 13 Amp fuse. There is no RCD on prior or after the transformer as it's superfluous in that situation.
On AC/DC sets or SMPS the use of an isolating transformer is mandatory even in the HSE documentation for the Radio & TV trade. One place I worked for (Brands that went bust in 2002) only had RCD protection for the benches (metal based and earthed) which resulted in numerous belts even with the RCD. Their H&S officer was allegedly trained with a certificate, I told her one did she get the certificate out of a "lucky bag"!! Two of us called HSE after one guy got a belt and split his head after falling. They came in and immediately closed the place until isolating transformers were installed.
You are more likely to have reflex action on AC to react and come off than DC. My 1.5kv isolating transformer would occasionally blow a 10 Amp plug fuse but is OK with a 13 Amp fuse. There is no RCD on prior or after the transformer as it's superfluous in that situation.
On AC/DC sets or SMPS the use of an isolating transformer is mandatory even in the HSE documentation for the Radio & TV trade. One place I worked for (Brands that went bust in 2002) only had RCD protection for the benches (metal based and earthed) which resulted in numerous belts even with the RCD. Their H&S officer was allegedly trained with a certificate, I told her one did she get the certificate out of a "lucky bag"!! Two of us called HSE after one guy got a belt and split his head after falling. They came in and immediately closed the place until isolating transformers were installed.
