Can somebody tell me why panel manufacturers in the USA (Eaton, Siemens, Schneider) don’t have the drip shields for lighting and receptacle panels for sprinklered buildings? This is very common practice in number of countries including Canada
I see following thread where RBULSARA stated having an emergency generator makes the rule (to feed the fie pump from the line side of the service) less stringent or even not required. Does anybody know if there's such a rule or document?
http://www.eng-tips.com/viewthread.cfm?qid=172599
The fire department and the electrical safety authority have accepted such installations even as last year. The requirement was introduced to the code almost at the same time it was introduced to NFPA70. Does anybody know if the fire pump is backed up by an Emergency generator, a waiver is...
Per Canadian Electrical Code, a separate service feeder ahead of the main building disconnect or a separate service directly from the utility transformer is required for the fire pump. Having said that I have seen many installations where the fire pump is fed from a branch lockable breaker from...
Per Canadian Electrical Code, a separate service feeder ahead of the main building disconnect or a separate service directly from the utility transformer is required for the fire pump. Having said that I have seen many installations where the fire pump is fed from a branch lockable breaker from...
davidbeach
That could be true. But since conductor installation should pass all other stringent requirements and the scenario is very rare, the code apparently does not mandate conductors to be larger than 125% FLA and 15% maximum starting voltage drop.
I found the correct explanation finally I think. Brian J McPartland's NEC 2011 Handbook has correctly explained the scenario. Basically it has conceded that the conductors are undersized to carry the LRA. But since this scenario happens very rarely, it does not pose a significant issue. See my...
Since I initiated this thread, I contacted Tornatech tech engineer. Their controllers can be set for LRA to run up to 20ms. Usually set it to between 8 to 20ms. This means it trips the circuit automatically if LRA flows more than 20ms. It happens both in automatic and manual mode too. In manual...
dpc- Even though NEC says 125% FLA, NFPA 695 calls to size the breaker to run LRA continuously. Having just now discussed with the TornaTech(one of fire pump controller manufacturers) tech support, there's no protection set time in their controllers. I am not contesting NEC but trying to find...
NEC requires 125%xFLA to be the minimum feeder size for the fire pump. But in order to carry the motor Locked Rotor Amps continuously, the breaker is usually sized to 600%xFLA. How is it possible for the feeder to carry Locked Rotor Current continuously if the feeder is under sized( i.e 125% x...
Mbrooke- Transfomer is 1500KVA and when the production is halted after midnight work shift and the offices are closed, only available load is the plant lights which is approximately 120KVA. So it means its around 8% and with some minor building ventillation fans coming on/off it may be around...
ScottyUK- it's not LV cables. Its 27.6K primary cable that's 438m underground run. They do not want to build up overhead in that area as is a flight manufacturing plant which requires flights to move around the area.
Hi
Does anybody know where theres a good reference or a document that suggests limitng length of cables terminating to a 1500KVA 27.6/600 delta-wye transformer? In my application total length of cables is approximately 438m (375m underground and the rest is above ground on a roof) before it...
Are you saying you have a TVSS protecting the fire alarm panel? Did it come with he fire alarm panel or you provided it between the circuit breaker and the fire alarm panel?
