We are looking to back feed power, in case of loss of our generator, through a circuit breaker from a branch feed used to load bank test a generator. The breaker will be a Square D PGA36100SA rated to 1000 amps at 480 volts. All other power to the building will be down while repairs are made to...
We are getting ready to do a major electrical shutdown to service our 13.2 kv switchgear. While we are down there are serveral items that get done on a regular basis including the DRLO scan of the busses & feeders. We have IR scans done every year and I am wondering about the value of the DRLO...
Just received a large tool to install that has a large area open for ventilation. I would be fine with that except a 6" wide by 36" tall part of that area leads into the electrical controls at 480V. Are there requirements for electrical cabinets to be enclosed, finger safe, and of sufficient...
Apparently we have tools that operate at 13.6 mhz and 2.54 ghz and I've been asked if we need to add RF & MW guidelines to our electrical safety policy. All the emmissions are supposed stay inside the tools but we have technicians that check boards and subassemblies that have busses with those...
Am I being overly restrictive and costing the company more money than necessary?
Our cleanroom floors are used for return air and running various utilities to the manufacturing tools. As such I believe they fall into the "other space used for environmental air" described in NEC 2008 300.22(C)...
I have been tasked with generating our electrical safety policy &, If I am reading OSHA 1910.335 and the NFPA 70E correctly, it would appear that anyone working on live electrical circuits above 50 volts needs to wear insulating gloves and protectors. Having worked my way through college as a...
A brand name motor drive manufacturer writes:
"Motor size is often increased by 1.2 to 1.5 times for load applications such as fans, blowers and pumps. Consequently, the motors in such applications are generally operating at 70% rated capacity when the rated output of the equipment is reached...
Is there a good resource for learning where and when to apply K-rated transformer and chosing the appropriate K factor? My training in is micro-electronics but I've been given 4 building electrical systems. Several areas here have non-linear loads that make up >50% of the transformer load & we...
We have some process piping I believe is 304SS that is being eaten in about 3 years. Is beryllium corrosive to stainless and if so what other alloys might be a better fit. Hastelloy?
I think I once read some where that circuit breakers are only tested to trip at the rated capacity 6 times. Haven't found anything recently to back that up. Is there something that states when a circuit breaker should be replaced based on the number of times it has tripped?
I have inherited two older substations with woven insulation on the 13,500V feeders. The wires are weeping some kind of fluids. The most common is brownish with a high viscosity. The other fluid is green and looks like water and copper corrosion to me. Do you have any idea what the brown fluid...
We have a generator that needs to be load bank tested. The output is 480V 3P 1000A. The test will be limited to 800A and we are installing a separate 1000A circuit breaker in an I-line panel to go to the load bank.
The methods I have seen so far for hooking up a rented load bank is to connect...
