This is a cool site and all that. But, everything is best in moderation. My self, a bit internalverted and engineering inclined has found that this is a vise, not unlike any other work place vise, you know, phones, BS'ing etc.
How do the "normal" people deal with this? Once a week? once a day...
I have been blessed to have been given the ability to participate in this forum, of an assorted assembly of exceptional engineering talent. Always amazed at the depth of knowledge that individually has been obtained in the many implementations, refinements, and re-refinements of the existing...
Are there some references as to the complex impedence based transfer functions of the inverter driven, shunt connected synchronous unloaded-motor filters used in some UPS systems?
For a Delta-Wye connected transformer, will non-balanced primary voltage be transformed through the transformer proportionally, or does the core-form construction re-balance the line?
According to NESC C-2 instrument transformers are not required over current protection. The NEC indicates all transformers need OCP. For medium voltage systems, in switchyards and on poles, is fusing of metering potential transformers optional?
Are there ramifications as to Power Quality metering performance on a 3-phase / 3-Wire MV line, comparing Delta connected PT's & CT's "corner" grounded, or Wye connected PT's & CT's, Star grounded, or some combination of the two. Technically this line is resistance grounded, but many miles away...
If multiple (seperately derived) class 2-control wiring enter a single "control panel" what are the code implications? Since the 120V motor controls are derived from independent sources of power, servicing the units can intoduce the potential of electrical shock.. etc/ no clear means of...
Talking to a sales rep, He stated that the fault current in LA was getting up to 40KA @ 34kV, that is 1.36GW of fault current. I have a hard time even comprehending this. Are these numbers correct?
We are starting to investigate replacement of indicating KW meters with new digital KWH meters, and adding new KWH meters where only Amp meters were before (by tieing into the PT bus). These are to be installed in substation instrumentation cabinets.
These meters share the CT's used with older...
The 1996 handbook includes a table. "Maximum-length equipment grounding conductor, copper, Al, Steel, EMT, IMT,GRC.... etc. Says that it generated by an SCA software developed by GIT for NEMA producers of steel EMT, etc, etc.
Sounds like free-ware, Anybody know if it is available on line?
When the HVAC manufacturer's list MCA, minimum circuit amps, for a unit, does this number already include the 25% extra required by NEC for feeder sizing?
I am starting to battle it out with an FPE about receptacles
under raised flooring, and the following
http://ecmweb.com/mag/electric_cords_fixture_wires/index.html
appears on the scene. Note figure 1, and the following caviot. "not used for environmental air". Plus no mention of 2002 art 645...
I have a 24Vdc 1/4hp motor PM-4 pole, that runs max efficiency at 10A. I have installed it is an evaporative cooler driving and propeller blower. I currently have 2-pully options, the first draws 9.5A, the second draws 12A. Now that is 2*24= ~50W over nameplate, maybe not optimum for the motor...
I hear it, and have used it. Do not see it in the power books. What is the cononotation, just an upstream feed to other stuff? (protected by it's own means.)
We have reached the electronic capacity of substriber telephone unit fire alarm reporting. Both in obsolete equipment issues and in basic propriatory limitations in functionality.
What are the big boys doing now days. Is it dual phone line, dual phone line code ID. Or is the prefered system now...
In the 80's the ney say'ers claimd that it took more energy to produce a solar panel than they would produce over the panel's effective lifetime.
This argument was somewhat snuffed out when one now defunct manufacturer of amorph panels claimed that they produced the panels using solar panels...
Is there a "utilities" standard for drawing single line diagrams of medium voltage distribution systems? I need to unravel a web of such, that has been tagged onto, and modified, and such for many years. My experence in commercial A&E is that the stuff is somewhat indivdualized.
I hate re-work...
It is a commonly taught that the phase velocity propogates at a velocity > the speed of light in waveguide systems. However, with the caviot that the information travels at the "group velocity", which is equal to or slower that the speed of light.
Question? by using multiple channels or...
I have heard that there is technology (in the USA) that allows the remote reading of meters, via, data over powerline. Is this technology compatible with substation level distribution feeders? Will it work through pad mount transformers?
