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
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...
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...
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...
The project I am working on is in Canada. It's looking for the LEED credit available for the Measurement and Verification(M & V). It's large scale existing industrial plant looking to expand. Expansion cost itself is around 320 million. So to install required meters to satisfy stipulated M&V...
I have Daikin Air-Conditioning units(Japanese) to be installed on a roof. They are approved by CSA and having UL/ULc certifications as well. Two condensor units are usually come together. The wiirng diagram shows one branch circuit to be brought closer to the units and tap or splice it to two...
MOCP=50
FLA=47
Can somebody tell me the procedure to select the breaker for above Roof Top AC unit. I am doing a project in Canada and bit confused with their code. The code is same as NEC but they do it differently.
If I did it accori8dng to NEC I would go with the 110A breaker with 50A trip...
Hi guys!
I have experience in several occasions installing Induction Motor Speed Controllers, one in a water desalination plant and others in process control environments. I would like to share the experience you guys have and how you rate the unit against Variable Frequency Drives. If anybody...
Hi fellows,
I need to compare and understand the best equipment available in the market that reduces THD (Total harmonic distortion). I am not concern about the money but the waste of energy. I know the use of k-rated transformers, lowpass filters and broadband filters. But they all waste...
I have seen indicator lights installed on distribution panels between the phases and neutral in most of panelboards manufactured to Japanese standards and some Asian countries. What happens to an indicator light installed between a phase and the neutral in case of an earth fault of that...
Hi Guys,
Can anybody guide me how to calculate the feeder and branch circuit protective devices and cables as per IEC or brtitsh methods. Where are the publications of locked rotor amps, temperature derating factors for cables can be found in the net? I am familiar with NEC/Canadian stds only...
I understand that by adding a capacitor bank to a low power factor motor control center or main switchboard(less effective) greatly reduces the current input, lowers the cable ratings and the cost of electricity. But what happens to the ampere interrupting rating of the downstream protective...
can anybody tell me why "Arc Fault Circuit Interruptors" are used and they are mandatory specially for bed room receptacles as per certain electrical codes. Also please let me know how we selectively coordinate them with other protective devices.
Can anybody tell me a software which I can use for fault calculations in electrical systems, conductor sizing and coordination analysis using ANSI/IEC standards. I know EDSA. But it is too expensive for me and if anybody knows a place from where I can get it installed.
Can anybody tell me a software which I can use for fault calculations in electrical systems, conductor sizing and coordination analysis using ANSI standards. I know EDSA. But it is too expensive for me and if anybody knows a place from where I can get it installed.
