I think some more meter readings are in order here, are you saying that the voltage from phase B to nuetral is only 240 when that one machine is running, or is it all the time, if you can go into this facility when machines are offline and check voltages, and if you have normal voltage readings...
Peepee please explain the science you used to determine that the Union in Chicago controls the areas electrical codes, I would think that the Chicago Inspection Department as well as the IBEW should take offense to that statement. I know that I personally do. P.T. Local #343, Minnesota.
voltage specs are considered to be nominal, 440, 460, and 480 for example are all considered the same for all practicle purpose, The actual voltage at which a circuit operates can vary from the nominal within a range that permits satisfactory operation of equipment.
is this setup on a bridge crane or similar and controls from pendant or is the winch stationary and operator station permanently mounted, if you want to do this from a pendant control then you will probably need to use a relay system but if it is a stationary set up then you need a drum switch...
just noticed this post now, probably a little late, I would think a VFD rated for twice the three phase horse power rating for your motor would be your best bet, you will have speed control, reverse, ramp up and braking properties if needed as well as motor overload protection all in one, these...
a loop detector imbeded in the concrete is what you are looking for, I have installed several of these but was only an employee so am not sure of who venders may be but I would try local overhead door companies for the loop materials, they use these to activate the door openers when forklifts...
This has all been very informative for me and I appreciate everyones opinion, I will build the rotory unit for now because I already have all the parts but in the future I will probably use a vfd for each application, thanks Tarzan.
I knew that VFDs could be used to provide three phase power to the smaller motors but was unaware that it was fesable for 10 hp motors, that is a good idea, but I guess the main reason for using a rotary converter is money, I will only have around $300 plus a day or two work into my rotary...
Just wondering if anyone has any experience with using both a ground fault recepticle in line with a arc fault recepticle, is it better to have one in front of the other? will one nuisence trip the other?
P.S. to tulum, I am sure you probably are regretting this post at times since it does stir up a lot of contraversy, I believe if you could design a small system possibly using an induction type generator and divert a small amount of the water without disturbing the natural flow of things you...
regardless of everyones opinion on wether or not hydro electric systems are more or less benificial to the enviroment it still needs to be submitted to your local department of natural resources or whatever governing agency in your area handles such matters, these installations do alter the...
I can think of a couple of ways to do this, personally I would use a double pole-double throw-center off dc motor rated toggle switch, connect A1 and A2 to the two common terminals then connect F1 to one of the remaining terminals and take a jumper wire from there to the terminal located...
For voltage drop calculations the NEC or NFPA 70 is not concerned with insulation type or thickness, if you refer to chapter nine, table eight in the back of 2002 NEC it will list conductor properties for voltage drop calculations
and ohms per one thousand feet of resistance for each conductor...
Just a thought but from a maintenance mans perspective you may have two problems, one as most agree would be a control circuit problem but the fact that one of the main contacts burned up would seem to me a possible loose connection anywhere from the bottom to the starter to the motor windings...
