Dan-Ark
Active member
My wife and I have recently finished a month of updates to one of our washes, new FRP panels in all the bays new signs and paint (which lasted less than 3 years since we bought and renovated the firs time). Anyway, we have started arriving at the wash to find the air compressor breaker (in the main panel) tripped on several occasions, usually a week or so apart. This started after a power failure in the area. it is 3 phase. unloader valve appears to be working every time, Amp probe shows all 3 legs drawing evenly around 18 amps or so (after initial surge). I swapped the 30 amp breaker in the panel. No change. Later I discovered when manually closing the starter contactor, the motor would sometimes hum instead of start and sometimes the contactor would stick closed cleaned the contactor best I could and operated it manually to get it working and ordered a new starter. A few days later I had a customer call me to tell me there was popping sounds coming from the equipment room. Arrived on scene to find air still in tank, but breaker popped and motor very warm. contactor stuck closed. jSuspect popping was PR valve on compressor. Bingo I thought. New starter it is.... Installed the new starter only to have my cleaning crew report the breaker was off the next day. I figured I forgot to turn it back on after finishing the starter install. 2 days later I go there again Sunday morning, NO AIR again. new starter appears to be working fine. I have added a backup compressor to save the business which after 5 days with no air during at least part of those days spread over the last month has certainly been affected. Now if the breaker trips and the main compressor does not come as the pressure gets a little lower, a portable 5hp will take over....BUT I need to fix this old 3 phase ingersoll rand ... Oh when the old starter would hum and not start I could easily manually move the pulley on the compressor so does not appear to be mechanical and most days it works perfect... Any Ideas??? About to pull the motor and take it to a shop to check it out. I have a theory that when the power company had their outage last month, perhaps all 3 legs didn't drop at same time and if the compressor happened to be running, it would have single phased. Only once did the heaters in the (old) starter trip, all other times it was the 30amp in the panel. It has only tripped once since I installed the new starter (assuming the first time was my not turning it back on, not sure that happened). Could a 3 phase motor run perfect most times but not go some times? all the pump stands are 3 phase as well as my automatic and have had no other power related issues.
