standard disconnect ? | Information by Electrical Professionals for ...
2008年1月18日 · The standard sizes of fuse disconnects are 30 A, 60 A, 100 A, 200 A and 400 A. There are probably some bigger sizes and smaller ones. Not sure of the amps.
Sizing fuses in a fused disconnect | Information by Electrical ...
2011年6月24日 · A 'fast' fuse can be as large as 3 x 13.6, or 40.8 amps. Next standard size is a 45-amp 'instant-trip' fuse. If I choose the far more preferred 'dual element' or 'time delay' fuse, I use 1.75 x 13.6, or 23.8. This would be a 25-amp fuse. In any case, a motor would need a disconnect that was rated for 1-1/2 horsepower, not any particular amperage.
Disconnect switch sizing | Information by Electrical Professionals …
2014年11月18日 · The NEC just says the disconnect has to be minimum of 115% of the load, but when it is a fused disconnect and you size the fuses for 125%, the minimum size of the disconnect is met by default. So that rule basically only counts for non fused disconnects or mains where there are branch circuit protection devices below it.
Disconnect Sizing | Information by Electrical Professionals for ...
2022年8月18日 · You are correct, after 200, 400 is the next standard size. A 400 amp non-fuse could be used or a 400 amp with 250 amp fuses if desired. I would go with the 400A disconnect fused at 250A option. If the fault current information is available and you know what the upstream circuit breaker is, it is possible that it will series rate.
Standard American and European Disconnect Switch Sizes
2015年12月21日 · Hi, I have a project that was designed to European standards. Now we have received a submittal for the disconnect switches where the submittal is for American standard sizes. For example, they want to use 30A disconnect switches instead of the 32A and 60A instead of the 63A. I mean it still...
208v 3 Phase Disconnect Sizing | Information by Electrical ...
2018年4月2日 · But to my main question. We are trying to calculate a service disconnect on a 3 Phase 208y/120. We are hooking up many appliances that are single phase loads. Our total appliance draw is 320,000 Watts. We need to know how to size the service disconnect and fuses. Thank you all in advance.
Bus Size and Frame Size | Information by Electrical Professionals …
Dec 20, 2014. #3. In my experaince Bus size = rating of bus in amps. This rating may be the same as the over current device or larger Frame size = the maximum rating in amps of breakers with rating plugs or fusable disconects. For example a breaker with a 200 amp frame size with a 150 rating plug. Z.
Fused disconnect wire sizing | Information by Electrical …
2020年11月17日 · The fuses protect the wire. The fuses then are based on the load, not the disconnect. If you put 400A fuses in there, the conductors would have to be rated for at least 400A (unless feeding a motor starter). The size of the disconnect is only relevant in that it has to be 115% LARGER than the load. How much larger is a function of your budget ...
Fuse sizing of a disconnect | Information by Electrical Professionals ...
2021年10月13日 · 1 100HP VFD, 124FLA - there is no branch circuit protection provided, max per documentation is 200A fuses (no minimums listed), and this I'm hoping can be covered by the main disconnect. 2 Motors, 2HP, 3.4FLA, each protected by an MPCB set at 3.4A.
Disconnect Size | Information by Electrical Professionals for ...
2024年1月11日 · Frame sizes for low voltage circuit breakers are different. Those are typically 125, 150, 225, 250, 400, 600, 800, 1200, 1600 etc. Those should be called out when specifying low voltage distribution equipment that use mounting inches instead of circuit spaces (ie, switchboards & power distribution panelboards).