These Transformers are usually reciprocal, and don't care which side you feed. Some caveats may apply if there are cooling fans, the other voltage is 100KV, this is connected as a wye to high-delta converter and so on.
for three phase the calculation is 30,000 = 1.73*V*I - simple as that. For single Phase the calculation is 30,000 = V*I - simple as that It is important to note the voltage in the first line is Line to Line (typically how it is specified in three phase power systems), and the second line it is Line to neutral. A 30KVA transformer is the same as 30,000VA to find out the Amps you need to divide the voltage if the transformer is single phase for example: 30,000VA / 480V = 62.5 Amps The calculation for a 3 phase transformer is the VA / voltage / 1.73 for example: 30,000VA /480V / 1.73 = 36.12 Amps
Since this transformer has a ratio of 1:2 the load current on the 480V side just has to be doubled. 85 x 2 = 170A on the primary. 40.8 KVA transformer. To prove this just find the KVA of both sides and they should be equal.
Ohms law says that watts are equal to volts times amps. 240v X 13.5a = 3240 va VA / 1000 = Kva So, your load requires 3.24 Kva. The transformer should have a rating greater than this as a safety factor, so you would choose the next larger size, in this case probably a 5 Kva transformer with a 480v primary and a 240v secondary. Your local electrical codes may require a larger safety factor, so you would want to consult them before buying the transformer!
Yes, with an auto transformer. It is a transformer with multiple taps on the winding. Connect the 208 volts across the common tap and 208 volt tap. Then connect the load across the common tap and the 240 volt tap.208 VAC usually comes from one floating side of a Delta 3 phase transformer.240 VAC usually comes from a grounded center tapped transformer.Using an autotransformer would be very hazardous and violate code. Probably tripping the 208 VAC breakers.The only way to do it correctly would be with a transformer with a 208 VAC floating primary and a 240 VAC grounded center tapped secondary.
Divide the amount of turns in the secondary into 32 V and you'll get 8. Now multiply 8 times 60 turns and you'll get 480V.
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Sounds like the wrong size fuse protection was used. The transformer should be protected to its kva capacity.
Most 3 Phase 480V Starters are controlled by 120VAC. This is because the coils on the contactors (starters) are 120VAC. Just ensure the voltage matches the coil.
Mathematically, just divide 480 by the square root of three. Electrically, 480V refers to the line-to-line value of a three phase system. For example, measure the voltage across A-phase and B-phase and you'll get 480V. 277V is the line-to-neutral value. Measure the voltage across A-phase and the neutral conductor and you should get 277V.
Five wires. Two on the primary side, connected to each 120V leg, giving a primary voltage of 240V. Two on the secondary side, one connected to neutral, and the other the new 480V hot. One connecting the frame of the transformer and the box containing it to ground. Note: you will only get one phase power out of this configuration - to get three phase output, you need three phase input, three transformers, and a lot more wires.
for three phase the calculation is 30,000 = 1.73*V*I - simple as that. For single Phase the calculation is 30,000 = V*I - simple as that It is important to note the voltage in the first line is Line to Line (typically how it is specified in three phase power systems), and the second line it is Line to neutral. A 30KVA transformer is the same as 30,000VA to find out the Amps you need to divide the voltage if the transformer is single phase for example: 30,000VA / 480V = 62.5 Amps The calculation for a 3 phase transformer is the VA / voltage / 1.73 for example: 30,000VA /480V / 1.73 = 36.12 Amps
there isnt a high leg in a three phase 480v panel only on 240v panels
im have a 30 kva transformer 3 phase 480v 80 amp panel 120v what size disconnect should I use
You can use a step-up transformer. Transformers are rated in primary voltage, secondary voltage, kVA, phases (single and three) and other parameters then equipped with indoor and outdoor enclosures. Be sure to consult a professional engineer or electrician when choosing and installing a step-up transformer. There are several NEC issues involved as well as choosing a transformer that is right for the type of load you have. One without the proper licensing AND knowledge of transformer circuits should never install 480V wiring or transformers.
Line voltage equals phase voltage multiplied by the square root of three. a.k.a. E l = E p X 1.73 In a 3 phase 480v system the phase voltage is 277v. Therefore E l = 277 X 1.73 = 480v
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.
Since this transformer has a ratio of 1:2 the load current on the 480V side just has to be doubled. 85 x 2 = 170A on the primary. 40.8 KVA transformer. To prove this just find the KVA of both sides and they should be equal.