2 Speed 1 Winding 3 Phase Motors
2 Speed 1 Winding 3 Phase Motors
(OP)
We have some new workshop machines purchased from abroad, the wiring diagrams for the motor starters are identical to the following:-
ht tp://www.s susa.cc/re ference/wi ring_diagr ams/standa rd_series_ drawings/s eries_110/ 110_01.pdf
The are rated at 2.2KW / 1.1KW, but both overload relays are set at 4A (bottom of their range).
Could anyone provide links to info on these type of motors, i.e whether they are star or delta connected when in low & high speed?
Cheers,
Alan
ht
The are rated at 2.2KW / 1.1KW, but both overload relays are set at 4A (bottom of their range).
Could anyone provide links to info on these type of motors, i.e whether they are star or delta connected when in low & high speed?
Cheers,
Alan





RE: 2 Speed 1 Winding 3 Phase Motors
it looks like the motors you have are dahadler tap wound constant torque. the leads should be marked u1 v1 w1 u2 v2 w2.
for high speed supply w2-u2-v2 join together u1-v1-w1
for low speed supply u1-v1-w1 (others open)
trust this will help.
kind regds
RE: 2 Speed 1 Winding 3 Phase Motors
I have a stupid question, if you care to answer.
The speed is decided by the no. of poles we say in any AC motor. Now, in two speed motors how are we able to change the speed by changing winding arrangement on the stator (when poles are on the rotor).
RE: 2 Speed 1 Winding 3 Phase Motors
If you add them up now, where the motor used to be N,S,N,S, you now just doubled the poles to N,S,N,S,N,S,N,S.
Hope that helps.
RE: 2 Speed 1 Winding 3 Phase Motors
RE: 2 Speed 1 Winding 3 Phase Motors
Answering your original question:
The power ratio provided is 2.2kW/1.1kW = 2, which shows a constant torque winding.
For constant torque, single winding the connections are; One Circuit Delta in low speed and Two Circuits Wye for high speed. That connection is exactly made by the sprecher+schuh magnetic starter in the link.
The full load currents regularly are very close due to a low P.F. (power factor) for the low speed connection. Two speed motors are a compromise to optimize the performance at both speeds.
RE: 2 Speed 1 Winding 3 Phase Motors
RE: 2 Speed 1 Winding 3 Phase Motors
RE: 2 Speed 1 Winding 3 Phase Motors
Here is a link, see the IEC section...
http://
RE: 2 Speed 1 Winding 3 Phase Motors
RE: 2 Speed 1 Winding 3 Phase Motors
RE: 2 Speed 1 Winding 3 Phase Motors
By direct switching, very high effect will be generatet and let into the mains, blowin the fuses.
In automatic starters you must install a timer to ensure this.
Greetings Aksel