What will I need to run 3 phase 208V machines with 480V coming into the building?
364172
First of all, you cannot turn a 240 V, 200 A service into a 480 V, 200 A service with a simple 3 phase transformer. In a transformer, power out (roughly) equals power in. If you put 83 kW in, you can't get 166 kW out. You will have your electric company run a new 480 V service for you. From "your side" of the service, you will have to have a licensed, qualified electrician make sure that all breakers, wiring, fuses, and other components are rated for 600 volts, so you may not be able to use your existing breaker box, or even the wire feeding it. All of your existing wire to motors and other 240 / 480 VAC devices should be of ample ampacity, as a motor draws half of the current at 480 than at 240, but again, it may be wired with 300 V wire that does not have insulation rated for 480 V circuits. Another investment would likely be a step-down transformer for your electrical outlets. You won't be able to go phase to neutral anymore, as that would get you 277 VAC (in a 4-wire Y system). Make sure that your qualified electrician complies with all local codes, as well as the NEC. Good luck!
143811
Aboslutely, provided the fans are for 12V service.  Leave the secondary center tap unconnected, and put each end of the secondary to the AC input of the rectifier.  The + goes to the red lead of the fan; the - goes to the black lead (traditionally speaking of course.) Now the supply will be very ripply, with a 120 Hz waveform which could be more than a volt.  If you put a 470uF 35V capacitor across the plus and minus of the rectifier, you will smooth out the ripple, but increase the voltage above 12 volts.  Make sure the fans can take the increased voltage.  Transformers are rated at the RMS output at the 3 amps in your case.  The peak voltage will be around 1.4*12.6, but in practice I have never seen it go above 15 V with a load.  Therefore at 1 amp, if you put a cap on the supply, it may produce excessive voltage.  Check it with a voltmeter-- you may luck out.\n\nI have been in a similar situation.  Get a 5 watt resistor at maybe 1 to 3 ohms.  Insert it in series between the capactitor positive and the fans wired in parallel.  When running, use a voltmeter on the fan circuit.  Increase the resistor till you get 12V or thereabouts.  The resistor will get hot, so leave the leads long and connect them to a terminal strip or block if possible, and mount it in the airstream.\n\nCheck out the LM7812, however, at 1 Amp.  Google it, or check out jameco.com for the part.  Put a 470uF at 35 V at each end of the regulator to keep things very smooth.  Your fan will run perfectly with the voltage regulator.  Be sure to mount the tab on a heatsink to keep it cool since you are running it at full capacity.
734859
Divide by the voltage and multiply by 1000.\n\nIf you are working with 3 phase power, divide again by sqrt(3)
80787
it shouldnt mater that much, 3 phase power fires one after another, if all three have the same voltage, amperage, and Hz. the only thing, that i can think of, is to make sure that they are cycling in order. DO NOT CONECT TO MOTOR, if the motor is conected and the wires are conected in the improper order, it will not run backwards, it will cause severe damage, as far as i know. runing backwards would only work in 2 Phase power, Maby. Be carefull when using multi-meters with 3 Phase power, i read on my meter that that source can be unpredictable and very dangerous. A good meter and good judgement can do a lot of help in this situation. I think that if you just guess and hook them all up, and be ready to turn it off quickly, then if it is incorect you just switch your b and c wires and it should work. if you have a meter i think that some power setups have the a and b lines at 115vac and c is higher, MABY! i do not know for sure how to discover for sure what they are, but i dont think that ossiliscopes are the corect tool for the job. good luck
1090847
I would just run it at 60 Hz. Output rpm will be 20% higher. \n\nAlternately, you could get a 400V VFD and set it's output to 50 Hz.
561818
Just be sure that you are not overloading the UPS. Check the rating on it!
160858
WELL..IF YOU ARE GOING TO CHANGE A DISLEXIC TO ACCEPT ELECTRICITY OR A LIGHT BULB THEN YOU BETTER MAKE SURE EVERYTHING IS UP TO CODE...YOU WILL DEFINATELY NEED A 220 VOLT SERVICE CONNECTION..
1184742
200 W is not much for modern computers.  I assume that if you don't add anything, things keep working.  The power supply need not explode or catch fire.  More likely the voltage levels drop under overload, and things stop working.
1177002
yeah you can use a switch (voltage switch) or if you can use binary logic, need to know how much voltage/current you are dealing with
827050
Yupp... but unfortunately is a hardcopy on my desk. Perhaps you may straight to tell us what\n\n1. You are designing from HT to Transformer 11kV / 415V\n2. You are designinig from Transformer to LV ??\n3. What is the kVA of the transfomer?
1083129
1. Motor driven Van de Graaff Generator.\n\n2. High voltage multiplier - Jacob's Ladder.\n\n3. High voltage induction coil - Tesla Coil.\n\n4. Flyback Transformer.
631034
The TXMR's must have the following to load share\n1 the same primary and secondary voltage windings\n2. of the same Phase relationship (vectors)\n3. have the same impedance %
821020
Each should be marked with a Vector Group Reference.\nThis gives phase angle and lead or lag angles. \nThese should be matched before connecting them.\nAfter connection the load should be introduced to the board in synchronism with the supply.
1038968
What voltage dc, or do you need to be able to vary it?  What current capacity do you need?  What ripple voltage is acceptable?
601207
Voltage drops for multiple lighting systems are usually handled by using 277 volt AC. \n\nThe multicore cable is something I have no working knowledge on.  Sorry better to say so than to BS you.
533546
You need two of those as fans. Connect them in series.\n\nOr...\n\nIf you don't have two of it, get an appliance which has the same rating and connect them in series.\n\nOr...\n\nPlug it to a voltage half its rating.
916579
You can't...\nYou may be able to get a 3 HP 12 volt motor at 4000 rpm but the battery would be huge and so would the motor. You could get a 110V 60hz 3hp motor at 4000 rpm.... Any standard electrical motor supply vender can get this for you