Coltri MCH6 wiring ?

So I purchased a 2012 Coltri MCH-6, it has a 220v motor. It showed up and I tried to use it, the motor just hums and makes my lights dim :(. I took the cover off the motor and check the start/run capacitors, they both tested good. i noticed one of the capacitors has “used” written on it and it is a 2004 capacitor, the unit is a 2012. I am not convinced it is wired properly, but I don’t have a way to check. I am trying to find a wiring diagram that is in English, that is proving to be difficult. I am wondering if anyone here has an English diagram for a 2012 or would mind taking the cover off theirs and sending me a few pictures of where the wires should be attached, specifically the brown / blue ones that come from the motor to the capacitor?

thanks,

dennis
 
 

So I purchased a 2012 Coltri MCH-6, it has a 220v motor. It showed up and I tried to use it, the motor just hums and makes my lights dim :(. I took the cover off the motor and check the start/run capacitors, they both tested good. i noticed one of the capacitors has “used” written on it and it is a 2004 capacitor, the unit is a 2012. I am not convinced it is wired properly, but I don’t have a way to check. I am trying to find a wiring diagram that is in English, that is proving to be difficult. I am wondering if anyone here has an English diagram for a 2012 or would mind taking the cover off theirs and sending me a few pictures of where the wires should be attached, specifically the brown / blue ones that come from the motor to the capacitor?

thanks,

dennis



Dennis,

I don’t know much of anything about electrical wiring or the intricacies of this compressor. However, I did find some info in the link below and I found it on the site of a company I was going to refer you to in order to get the answers you’re looking for (page 10 has a wiring diagram). Unfortunately it’s probably the same one you’ve seen in Italian, although the rest of the manual appears to be in English. https://www.nuvair.com/manuals/MCH-6_r00%2001-2015.pdf

If the answers aren’t here, I suggest contacting Nuvair and asking someone with technical support. They’re a pretty large Coltri distributor based in Southern California. Have you attempted to get any information from the person/company that sold you your compressor? I hope you find what you’re looking for. 
 
Could this be of any help?

https://clr.es/blog/en/single-phase-two-phase-three-phase-motors/

https://en.wikipedia.org/wiki/Two-phase_electric_power

https://askinglot.com/is-house-220v-single-phase

https://www.hobby-machinist.com/threads/why-is-220v-called-single-phase-when-it-has-two-phases.17428/



I do not know how your 220V works is is two phases and ground?

Or is it a 400V single phase and zero?

A single phase motor should be akin to an European 220V and wiring the same.

A two phase thing is a different beast altogether, see above explanation.


 
If the motor hums don't keep it on it for even a second or you'll fry something inside. Have you tried disconnecting the fan belt to see if the compressor is binding which would stall the motor?. When a motor hums it usually isn't from an incorrect wiring pattern. It usually means that the start or run capacitor is malfunctioning, or there is a short in the motor windings in which case the motor is beyond repair. Have you tried starting the motor without the fan belt attached? Have you spun the pulley to see if there is any binding? If you just bought the compressor I doubt you'll find incorrect wiring is the culprit. It's likely a short or bad capacitors.

Replacement 3 HP motors will cost anywhere from $150-300. Make sure the base of any replacement motor is the type that will fit on your compressor chassis. Also get one with a pulley diameter that matches the existing motor. Hopefully you'll just need a capacitor.
 
If the motor hums don't keep it on it for even a second or you'll fry something inside. Have you tried disconnecting the fan belt to see if the compressor is binding which would stall the motor?. When a motor hums it usually isn't from an incorrect wiring pattern. It usually means that the start or run capacitor is malfunctioning, or there is a short in the motor windings in which case the motor is beyond repair. Have you tried starting the motor without the fan belt attached? Have you spun the pulley to see if there is any binding? If you just bought the compressor I doubt you'll find incorrect wiring is the culprit. It's likely a short or bad capacitors.

Replacement 3 HP motors will cost anywhere from $150-300. Make sure the base of any replacement motor is the type that will fit on your compressor chassis. Also get one with a pulley diameter that matches the existing motor. Hopefully you'll just need a capacitor.

That and correct rotation!

CCW or against the clock seen from the axle.
 
Thank you for all the help!!! After a bunch of research I figured out someone had wired the start and run capacitors wrong, given that there is no easy wiring diagram it was fun to figure out :). Once I figured out which winding was start and which one was run I was able to rewire the motor and it works!! Now that it works I will have to start a new thread, when I let it build up pressure and shut it off I can hear air bleeding back into the oil (guessing by the sound. It will actually spin the compressor backwards about 1/2 a turn ….. I am starting to think I should have spent $2,700 on a new one.