I agree that the use of "series Rating" is quite common on commercial projects where cost is of primary concern, but it has some severe restrictions which require special attention.
In addition it may not be used on emergency power systems, and should not be used where service reliability is...
Peebee, with respect, article 220-13 establishes permissible demand loads for general purpose receptacles rated at not more than 180 VA each.
I believe everyone that has ever designed an electrical system would agree that it is very unlikely that all of the connected load of an electrical...
With respect to jbartos and in regards to his response to my response: The hypothetical says 400 amp overcurrent protection.
Your commentary on the derating of circuit breakers is partially correct (for long continuous loads), is incorrect for "100% rated" circuit breakers, and is hardly...
Your hypothetical question is incomplete:
1. If the 400-amp panel has 400-amp protection ahead of it, the panel can have any combination of circuit breakers totaling up to 4200 amps (42 branch circuits, each at 100 amps). (This assumes the panel is one typical 42 circuit branch panel with 100...
"Facts"
Existing facility has three 400 KW 2 cycle diesel engine generator sets and wants to add a fourth 400 KW 4 cycle engine generator.
Pitch of new generator is not same as existing generators, but is "compatible".
Question:
Because 2 cycle engine has a much faster recovery time (from lump...
You may find the article at the end of this link (http://www.usawire-cable.com/techpapers/tempratings.htm) of interest. It deals with three different time frames: Normal; emergency overload; and fault conditions.
Since the emergency overload is "long duration", this may be what you seek.
Your comments are all correct and valid, but there are relative factors in operation here.
Regarding the wire sizing and energy saving aspec:
losses in wire is the result (product) of amperage squared X resistance (I^2 X R)
What you have been told regarding wire size is true, but perhaps not...
STEPE:
1. Regarding the existing ground at the existing panel, soon to be a junction box:
A. The existing service ground must be lifted at this location. If you keep the existing earth ground and make another (proper earth ground at the main servic equipment, you wll have providedmultiple paths...
I remember some discussion of the Bay of Bundy in the past.
I also am aware that there has been some preliminary work on using wave action to create compressed air (with the thought of using the compressed air to drive a turbine).
Mainepepmp mentioned GFCI required circuit protection for bedrooms: right neighborhood; wrong address.
Starting with the 1999 National Electrical Code/2002 California Electrical Code, circuits serving bedrooms require AFCI (Arcing Fault Circuit Interrupter) protection.
Only your local...
Several items for your consideration:
1. Although you do not mention it, if the the existing panel was the original service panel for the structure, it was required to have a ground to earth (probably via a cold water pipe). This original ground must be isolated from the old panel's neutral bus...
Although there is not a Code requirement per se, there is hidden in the National Electrical Code (in the NEC Handbook commentary for article "310-15 Ampacities.") some sage advice.
In sum and substance, the advice is to maintain conduit Center to Center spacing as would be used in...
