- Jan 31, 2018
- 1,276
- 1,211
- 1,688
- If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
- United Kingdom
- What type of forum member are you?
- Practising Electrician (Qualified - Domestic or Commercial etc)
- If other, please explain
- SJIB/SECTT recognised apprenticeship.
SVQ level III electrical installation.
City and guilds 2382 (18th)
City and guilds 2391-52 (I&T)
City and Guilds 2919 (EV Charging)
- Business Name
- MFS Electrical
Replaced an old TP&N Dorman Smith DB the other week there with a nice shiny new one, So being a nosy sod and wondering why old dorman smith breakers don’t ever seem to trip I decided to drill out the rivets and have a peek inside.
All I can say is no wonder they never trip
there is no coil inside to trip it instantaneously in the event of a short circuit! they only protection they provide is via a (quite hefty) copper strip so really only an overload or a fault of epic proportions is ever going to trip these bad boys.
Pics to follow once I drill out the rivets and carefully dismantle another the first one is in about a million pieces on my desk
i drilled out a modern breaker proteus side by side for comparison that too is in a million pieces but I have lots more and I’ll drill them out and post pics for comparison.
All I can say is no wonder they never trip
there is no coil inside to trip it instantaneously in the event of a short circuit! they only protection they provide is via a (quite hefty) copper strip so really only an overload or a fault of epic proportions is ever going to trip these bad boys. Pics to follow once I drill out the rivets and carefully dismantle another the first one is in about a million pieces on my desk
i drilled out a modern breaker proteus side by side for comparison that too is in a million pieces but I have lots more and I’ll drill them out and post pics for comparison.
