We are moving a hoist from a location in Pe. to our Ar shop. It was supposedly in working order and when we tried to wire it up it is malfunctioning. When you press either the up or down buttons sometimes nothing occurs and sometimes the coil of the contactor will momentarily pull the contacts in but its just a quick in and an out. This happens on both the up and down buttons. Voltage to the unit was 480V and the only odd thing i found so far is that the voltage coming off a transformer that should be 48V is
56V. This is what is going through the buttons to the coil of the contactor. I have the wire diagram and everything seems to be ok. I wondered if this could be caused by having a large voltage drop on the line that is only there after bushing in the buttons. When i push buttons and it energizes the coil it kicks out to fast to notice if the line voltage is dropping of if coil voltage is either. Its also 97degrees here and this is all out in sun so I'd really like to solve the problem Ken- posted
14 years ago