- Joined
- Aug 4, 2015
- Messages
- 291
Curious to see how this turns out. I know it was discussed about bringing in 120 control voltage from another source and it needing to be properly labeled but don't forget about lockout tag out requirements if this is in an industrial setting (I assume since you are running the unit on 480 it IS in a business and not a home or back garage. Only other thing I will say about the call a professional, that is a specific description to a broader statement. There are a number of folks around that are plant or shop electricians that you may even know that would probably assist you in your endeavors for a six pack after the work is done. I have done many things for pizza and coke (I don't drink beer). Again I know it's been stated, but it's significant enough to repeat, 480 3 phase is unforgiving to mistakes. The reason is two fold. The first is that most people that tell you they got hit by 220 frankly didn't. It takes being across both phases in a residential setting to get hit by 220. So even if you were wiring up your drier or stove and it shocked you,,, it was only 120 volts. 480 is 277 to neutral, if it hits you, you will typically never know it. You're just gone. Some survive it, but it's typically always bad. You will never just say damn that hurt. Second as mentioned earlier is 480 will create a sustaining arc. I personally watched a guy wire up an exterior light that didn't have good coloring of the wire (it was a multivoltage light) he connected it for 277 and it should have been 480 wired. When the 600 amp fuse finally let go the panel that the breaker was in he flipped finally quit glowing red. The arc created from the breaker blowing open held and worked out of the breaker and to the buss bars in the panel. It vaporized the copper bus bars from the bottom of the panel where the breaker was at up to almost the input lugs. All the insulation for all the wiring in the panel was burnt away, and the repair ended up being close to $7000 to replace the panel, install an enclosure above the panel, cut and terminate all the conduit back to the enclosure and extend the wiring down to the new breaker panel. It of course could have been much worse. Of course it blew the light in question off the side of the building and into the parking lot. But that was minor. Finding a professional doesn't necessarily mean spend a bunch of money. And be aware of something else. Since you are most likely in an industrial setting and not in your back garage. Most zoning and code enforcement does require a licensed electrician to work on commercial electricity. And remember that it has to be wired that only one contactor can be closed at a time. If you allow both the forward and reverse contactor to close it WILL blow your control box right off the machine and tend to do all the other ugly stuff mentioned above.
