Y-Delta starters in elevators
Y-Delta starters in elevators
(OP)
OK, pardon my ignorance, but I just cam across a curiosity that has me baffled. Open transition Y-Delta starters that use only 2 contactors! I don't yet know how they are wired because I have seen them only on a bench, but everyone assures me that they are not 2 out of the usual 3 contactors, they are using only the 2. They are mechanically interlocked so that only one can be closed at a time and one of them has a shorting bar across the top. As I said, I don't yet know the wiring configuration, but for the life of me, I cannot figure out how they are able to do anything useful! Has anyone else ever come across this? Apparently, it is very common in the elevator world.





RE: Y-Delta starters in elevators
RE: Y-Delta starters in elevators
Means there permanently three phase on one end of the windings, but you can still start and stop the motors OK. - saves the cost of one contactor.
Best regards,
Mark Empson
http://www.lmphotonics.com
RE: Y-Delta starters in elevators
RE: Y-Delta starters in elevators
Marke, that may be it!
RE: Y-Delta starters in elevators
RE: Y-Delta starters in elevators
Classic case of not doing the obvious and to bad about the safety.
Best regards,
Mark Empson
http://www.lmphotonics.com