Phase converter

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Patjmartino84

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Location
New jersey
Occupation
Electrician
Installing a 30 amp phase converter.
The feed is a 30 amp 240v line 175ft away.. I used #6 for the feeder to a fused disconnect.
Haven’t done one of these yet. With going through article 455. Just wanted to get some insight on the calculations for the load size of the wires
 
If you give it a 30A single phase feed, the 3 phase load cannot be more than 17A, and if it is a motor, even less than that.

If you NEED 30A at 230V 3 phase, then the input current will be 52A, and again, if it is a 30A motor, the phase converter will need to be able to handle the starting current.
 
455.6 A note: says: single phase conductors sized to prevent a voltage strap, not exceeding 3% from the source of supply to phase converter may help ensure proper starting and operational of motor loads
That being said, I am only at a 1.93 voltage drop
455.6a1&2 make it so eh
1: says the conductor capacity shall not be less than 125% of the nameplate of the converter so that right there says I should be good?
 
Jraef said:
If you give it a 30A single phase feed, the 3 phase load cannot be more than 17A, and if it is a motor, even less than that.

If you NEED 30A at 230V 3 phase, then the input current will be 52A, and again, if it is a 30A motor, the phase converter will need to be able to handle the starting current.
Click to expand...

Article 455 - Phase Converter MOCP + Conductor Sizing

Im helping someone with a design that is uncomfortably un-familar for me. We have some fixed load bakery equipment that we are required to run through a phase converter to power a few pieces of equipment. The phase converter is feeding a panel and the panel feeds the equipment. I have used a...
forums.mikeholt.com
Found this article
 
I think you may have missed @Jraef 's point.

When you say '30 A phase converter', do you mean a converter supplying 30A of 3 phase current, or a converter supplying a 30A 3 phase motor load, or do you mean a converter intended to connect to a 30A single phase circuit. What exactly do you have?
 
winnie said:
I think you may have missed @Jraef 's point.

When you say '30 A phase converter', do you mean a converter supplying 30A of 3 phase current, or a converter supplying a 30A 3 phase motor load, or do you mean a converter intended to connect to a 30A single phase circuit. What exactly do you have?
Click to expand...
It’s 30amp rotary motor. Supplying power to a 208 miter saw
The supply feeder is a single phase 30 amp
 
Sounds like it’s roughly 5 hp, you will need a 10 hp rotary converter with a minimum 40 amp input breaker, more likely a 50 or 60, since it will have a rotating mass to turn when starting.
 
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