Three-phase four-wire 480V voltage, what should the control voltage be?
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This post was last edited by soy sauce PK Beer on 2017-1-10 at 21:36. We have developed a set of export equipment; the power supply for its electrical system is three-phase four-wire at 480V, which means the single-phase voltage is 277V. According to the standard in China, where the voltage for power circuits is 380V and that for control circuits is 220V, shouldn’t the voltage for the control circuits inside the cabinet be set at 277V? However, I see that most of the components and coils operate at voltages other than 277V. What should we do? If voltage conversion is needed, are there any standard transformers that can do it? Thank you
The control voltage depends on how your control circuit is designed. If alternating current is used, it is usually single-phase voltage, which is 277V. If a DC system is used, it is generally DC220V in China.
If using domestic equipment, a single-phase transformer has to be custom-made. This has to be custom-made.
Add a control variable; using two phases on the primary side at 480/120 is sufficient.
Hey fellow sea traveler, this voltage standard is usually adopted by Americans or in some parts of North America! It is important to note the parameter requirements for the power supply provided by the purchaser; in particular, the frequency of the power supply is usually 60HZ, and all electrical control components selected must also be compatible with 60HZ, otherwise problems will arise! In North America, the standard three-phase supply voltages include 240V/480V, etc., and a single-phase supply voltage of 120V is definitely available. For the power distribution control cabinets they supply, it is preferable to use a secondary control voltage of 120V (there is no 277V voltage level available!) ). If a 120V control voltage is used, a 480/120V control transformer must be added to the control circuit. The capacity of this control transformer can be determined based on the total power consumption of the secondary components; generally, for small control cabinets, a control transformer with a capacity of no more than 1KVA is sufficient to meet the requirements.
Hey fellow sea traveler, this voltage standard is usually adopted by Americans or in some parts of North America! It is important to note the parameter requirements for the power supply provided by the purchaser; in particular, the frequency of the power supply is usually 60HZ, and all electrical control components selected must also be compatible with 60HZ, otherwise problems will arise! In North America, the standard three-phase supply voltages include 240V/480V, etc., and a single-phase supply voltage of 120V is definitely available. For the power distribution control cabinets they supply, it is preferable to use a secondary control voltage of 120V (there is no 277V voltage level available!) ). If a 120V control voltage is used, a 480/120V control transformer must be added to the control circuit. The capacity of this control transformer can be determined based on the total power consumption of the secondary components; generally, for small control cabinets, a control transformer with a capacity of no more than 1KVA is sufficient to meet the requirements.