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For a single-phase transformer, divide the ratedapparent power (expressed in volt amperes) by the voltage rating (expressed in volts) of the primary winding; this will give you the rated primary current (expressed in amperes) of the primary winding.
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Is the kva rating of a three phase generator per phase or a total of the three phases example is a 3 phase 75 kva generator 25 kva per phase or 75 per phase?
The kV.A (not 'kva') rating is the total apparent power of the machine. So a 75 kV.A machine is 25 kV.A per phase.
Transformer 208 volt primary and 480 volt secondary three phase 75 kva what size fuses on primar and secondary?
200 and 100
What is the minimum load require to put transformer?
A transformer requires a 75-kVA minimum load in order to be set.
How many output amps is a 75 kva transformer?
For single phase, KVA = (line to ground) * (phase current). A 75kVA 480 to 208Y/120 volt transformer is a fairly common transformer. I assume this is the type of transformer you are referring to. 75k / 120 = 625 Amps. As an FYI, the 208Y voltage is the line to line voltage, which is equal to (phase 1) - (phase 2), where the phases are separated by 120 degrees, thus (phase 1) * 1.732 For three phase, kVA = (line to line voltage) * (phase current) *(sqrt 3), 75k / 208 / 1.732 = 208 Amps.
How much to run a 75 KVA transformer with no load?
75 kV.A is the rated apparent power of the transformer which it can supply, continuously, to a load without overheating. When the transformer is not supplying a load, the primary current is (a) very small and, (b) lagging the supply voltage by practically 90 electrical degrees. Bear in mind that energy losses only occur for the component of current that is actually in phase with the supply voltage. So the energy consumed to the transformer is very small and is due to the resistance of the primary winding (copper loss) and a relatively small loss in the core (iron loss). Just how much energy this accounts for and, therefore, how much it costs to run the off-load transformer, is not possible to tell without knowing the full specification of the transformer.
Is the kva rating of a three phase generator per phase or a total of the three phases example is a 3 phase 75 kva generator 25 kva per phase or 75 per phase?
The kV.A (not 'kva') rating is the total apparent power of the machine. So a 75 kV.A machine is 25 kV.A per phase.
Transformer 208 volt primary and 480 volt secondary three phase 75 kva what size fuses on primar and secondary?
200 and 100
What is the minimum load require to put transformer?
A transformer requires a 75-kVA minimum load in order to be set.
How many output amps is a 75 KVA generator single phase?
The formula you are looking for is , A = kva x 1000/Volts.
How many amps will a 45 KVA transformer produce at 480 volts?
Each phase supplies 15 kVA. The primary has a line-to-neutral voltage of 277 v so the line current is 15,000 / 277 or 54 amps. The secondary has a line-to-neutral voltage of 120v so the current is 15,000/120 or 125 amps.
How many output amps is a 75 kva transformer?
For single phase, KVA = (line to ground) * (phase current). A 75kVA 480 to 208Y/120 volt transformer is a fairly common transformer. I assume this is the type of transformer you are referring to. 75k / 120 = 625 Amps. As an FYI, the 208Y voltage is the line to line voltage, which is equal to (phase 1) - (phase 2), where the phases are separated by 120 degrees, thus (phase 1) * 1.732 For three phase, kVA = (line to line voltage) * (phase current) *(sqrt 3), 75k / 208 / 1.732 = 208 Amps.
1 12hp motor takes what kva?
12HP is approximately 10.8 KVA. You would want to use a 15KVA transformer to supply this motor. KW = HP * .75 KVA = KW * 1.2 (These formulas are approximate)
How many volts per hour does a 75 kva transformer produce?
Volts per hour is an invalid statement. You may have meant Watts per Hour.
What size main breaker feeding 480v 75 kva transformer?
An exact breaker size can not be given because the voltage, and hence the calculation for current, is not given. A transformer shall be protected by an over current device that is not rated at more that 150% of the primary current.
How much to run a 75 KVA transformer with no load?
75 kV.A is the rated apparent power of the transformer which it can supply, continuously, to a load without overheating. When the transformer is not supplying a load, the primary current is (a) very small and, (b) lagging the supply voltage by practically 90 electrical degrees. Bear in mind that energy losses only occur for the component of current that is actually in phase with the supply voltage. So the energy consumed to the transformer is very small and is due to the resistance of the primary winding (copper loss) and a relatively small loss in the core (iron loss). Just how much energy this accounts for and, therefore, how much it costs to run the off-load transformer, is not possible to tell without knowing the full specification of the transformer.
How to convert from kV into kW?
Multiply by Amps.
Full load copper loss of a 100 KVA transformer is 800W Its copper loss at 75 percent load will be?
100 is to 800 as 75 is to X. Cross multiply, 100 x X and 800 x 75, 100X = 60000. To get rid of the 100 divide it into both sides of the equation. X = 600. If the copper loss is linear, at 75 percent the copper loss will be 600 watts.
