Multi-way plugs and sockets. - UK Vintage Radio Repair and Restoration Discussion Forum

joebog1 · 31st Oct 2019, 3:32 am

Are plug and socket covers available to protect my old fingers from contact with 500 volts?

There were a series of octal plugs and sockets made in Asia somewhere years ago, with push on PVC covers! They mostly slipped off, rather than covered the internal to the connector, voltages.

I have been using "Standard Circular Aircraft Connectors" from eBay to overcome this. They are not expensive, but I wonder about the ratings supplied:
500 volts DC and 5 amps per pin. They DONT specify if its only one pin loaded, or all pins loaded.

Old 11 pin and even octal plugs/sockets withstood 500 volts for years without failure.

Joe

Herald1360 · 31st Oct 2019, 12:09 pm

"Old 11 pin and even octal plugs/sockets withstood 500 volts for years without failure."

Given the relative pin spacings shouldn't that be:

"Old octal plugs/sockets and even 11 pin withstood 500 volts for years without failure."

For confidence (or otherwise) in any ratings, check the creepage and clearance distances in the connectors against some recognised standard. If the connector environment is benign (cool-warm and dry) you can be a bit more "relaxed" for personal domestic use

G6Tanuki · 31st Oct 2019, 12:24 pm

Though they're only 'officially' rated at 250VAC, I have used these sorts of Bulgin connectors for 500VC cabling [between power-supplies and transmitters] in the past.

https://uk.rs-online.com/web/p/compa...ctors/0487384/

emeritus · 31st Oct 2019, 12:44 pm

I have noticed that my octal and 11-pin valve-base relay sockets have grooves between adjacent pins, evidently to increase the surface distance between pins so as to increase the creepage distance. My understanding is that dielectric failure rarely occurs though the bulk of a body, but almost invariably happens at the air-surface interface. Equipment such as connectors intended for use on unpressurised aircraft need to have increased clearances as the dielectric strength of air falls with falling pressure. The connectors mentioned should in practice be OK at ground level.

31st Oct 2019, 3:32 am	#1
joebog1 Banned Join Date: Jun 2015 Location: Mareeba, North Queensland, Australia Posts: 2,704	Multi-way plugs and sockets. Are plug and socket covers available to protect my old fingers from contact with 500 volts? There were a series of octal plugs and sockets made in Asia somewhere years ago, with push on PVC covers! They mostly slipped off, rather than covered the internal to the connector, voltages. I have been using "Standard Circular Aircraft Connectors" from eBay to overcome this. They are not expensive, but I wonder about the ratings supplied: 500 volts DC and 5 amps per pin. They DONT specify if its only one pin loaded, or all pins loaded. Old 11 pin and even octal plugs/sockets withstood 500 volts for years without failure. Joe

31st Oct 2019, 12:09 pm	#2
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Multi-way plugs and sockets. "Old 11 pin and even octal plugs/sockets withstood 500 volts for years without failure." Given the relative pin spacings shouldn't that be: "Old octal plugs/sockets and even 11 pin withstood 500 volts for years without failure." For confidence (or otherwise) in any ratings, check the creepage and clearance distances in the connectors against some recognised standard. If the connector environment is benign (cool-warm and dry) you can be a bit more "relaxed" for personal domestic use __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O Last edited by Herald1360; 31st Oct 2019 at 12:15 pm.

31st Oct 2019, 12:24 pm	#3
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,005	Re: Multi-way plugs and sockets. Though they're only 'officially' rated at 250VAC, I have used these sorts of Bulgin connectors for 500VC cabling [between power-supplies and transmitters] in the past. https://uk.rs-online.com/web/p/compa...ctors/0487384/

31st Oct 2019, 12:44 pm	#4
emeritus Dekatron Join Date: Jan 2012 Location: Brentwood, Essex, UK. Posts: 5,345	Re: Multi-way plugs and sockets. I have noticed that my octal and 11-pin valve-base relay sockets have grooves between adjacent pins, evidently to increase the surface distance between pins so as to increase the creepage distance. My understanding is that dielectric failure rarely occurs though the bulk of a body, but almost invariably happens at the air-surface interface. Equipment such as connectors intended for use on unpressurised aircraft need to have increased clearances as the dielectric strength of air falls with falling pressure. The connectors mentioned should in practice be OK at ground level.