- Joined
- Sep 22, 2010
- Messages
- 898
Ron
To the best of my knowledge, I have never seen an RPC that could increase the voltage. IF you feed it with 220V single phase, you will get 220 V 3 phase output.
The next step is to add a 3 phase 220V to 440V step-up transformer.
Now if you look at the wiring diagram for a RPC, you will notice that the Black and Red wires go from the input breaker and continue, unbroken throughout the entire RPC. So even if the generator motor is not turning, there is still 220V single phase being applied to two legs of the three phase motors etc. The transformer needs to be protected from ever being energized in this way so a magnetic contactor (called in this instance as a Timing Line Contactor), large enough to handle the current load is placed between to output of the RPC and the input of the transformer and wired so that it will only energize if there is voltage present in the third leg.
Personally I prefer to size the TLC Contactor to handle the complete output of the RPC, that way, no motor on the circuit will ever see single phase as voltage will only ever pass beyond the TLC if the 3 phases are all present.
Now going the 220-440V transformer route will increase the cost of your installation by the cost of the transformer and possibly a distribution centre for the 440V. If you are only going to ever run the one machine, then you can wire it directly into the output of the transformer, but you will need to make sure the input of the transformer is properly fused. If you may ever get other machines that could run on 440V then look into a 3 phase load centre and breakers so that you can divide the output of the 440V to each machine.
Now as to your other option, rewiring the mill to 220V. That may be possible, but you will have to look at a few things. The motors have to be dual voltage and you have to rewire each motor to suit the 220V (some motors like 2 speed motors are only single voltage). More importantly is the coils in the contactors and any control transformers and any lights. If the coils on the magnetic contactors are 440V, they will need to be replaced with 220V coils. Many times though, the contactors may be low voltage, say 24V (this keeps high voltages away from the push button switches that us humans will be pushing) and there will be a transformer to step the input voltage down to that voltage. Once you have determined how many changes need to be done, you may find it easier to rewire to 220V or you may find that going plug and play, IE step-up transformer off the RPC will be better.
Walter
To the best of my knowledge, I have never seen an RPC that could increase the voltage. IF you feed it with 220V single phase, you will get 220 V 3 phase output.
The next step is to add a 3 phase 220V to 440V step-up transformer.
Now if you look at the wiring diagram for a RPC, you will notice that the Black and Red wires go from the input breaker and continue, unbroken throughout the entire RPC. So even if the generator motor is not turning, there is still 220V single phase being applied to two legs of the three phase motors etc. The transformer needs to be protected from ever being energized in this way so a magnetic contactor (called in this instance as a Timing Line Contactor), large enough to handle the current load is placed between to output of the RPC and the input of the transformer and wired so that it will only energize if there is voltage present in the third leg.
Personally I prefer to size the TLC Contactor to handle the complete output of the RPC, that way, no motor on the circuit will ever see single phase as voltage will only ever pass beyond the TLC if the 3 phases are all present.
Now going the 220-440V transformer route will increase the cost of your installation by the cost of the transformer and possibly a distribution centre for the 440V. If you are only going to ever run the one machine, then you can wire it directly into the output of the transformer, but you will need to make sure the input of the transformer is properly fused. If you may ever get other machines that could run on 440V then look into a 3 phase load centre and breakers so that you can divide the output of the 440V to each machine.
Now as to your other option, rewiring the mill to 220V. That may be possible, but you will have to look at a few things. The motors have to be dual voltage and you have to rewire each motor to suit the 220V (some motors like 2 speed motors are only single voltage). More importantly is the coils in the contactors and any control transformers and any lights. If the coils on the magnetic contactors are 440V, they will need to be replaced with 220V coils. Many times though, the contactors may be low voltage, say 24V (this keeps high voltages away from the push button switches that us humans will be pushing) and there will be a transformer to step the input voltage down to that voltage. Once you have determined how many changes need to be done, you may find it easier to rewire to 220V or you may find that going plug and play, IE step-up transformer off the RPC will be better.
Walter