Help with Electric Motor Identification - Dual Voltage vs Two Speed - 3 Phase AC Synchronous

Thread Starter

SimpleOne

Joined Dec 22, 2014
12
Well this in the OP threw me!
Well, same outcome, just not with the typical terminal studs and straps etc :)
The way it is now, is identical to if you strapped across U2, V2, W2 in such a box, thus bridging/bonding for a Star/Wye configuration.

I'll rewire it in Delta and see how the winding resistance compares, get some sort of ballpark on the current flow will be under 415V 3P and see if it looks reasonable for the field winding wires (which are pretty small, but I guess it's only 360w motor after all). If that all looks like it won't immediately produce nuclear armageddon, then I'll hook it up to power and see what happens.
 

Thread Starter

SimpleOne

Joined Dec 22, 2014
12
Well if strapped across as shown then it is set for star operation only! ?
Max.
That's sort of the point. If it were for star only, surely you wouldn't bother to expose the other end of the windings, and even if you did, surely an OEM wouldn't choose to terminate those other ends with just a screw clamp?
Compared to everything else in the setup, doing that just seems a bit to ad-hoc, as if it is deliberately intended to be customisable (for dual voltage), or they use the same motor for both one and two speed models, just without the two speed control circuitry added to the single speed ones?
 

Thread Starter

SimpleOne

Joined Dec 22, 2014
12
The other exposed ends of the winding's would normally go to the 3ph supply??
Max.
Just so we are on the same page and aren't getting our wires crossed (no bad pun intended). I have all the following winding terminals available to wire: U1, U2, V1, V2, W1, W2.

As such, I can do either: (where >>> means these terminals are connected)

Star:
L1 >>> U1
L2 >>> V1
L3 >>> W1
W2 >>> U2 >>> V2
(This is how it is currently)

Or, I could do:

Delta:
L1 >>> U1 >>> W2
L2 >>> V1 >>> U2
L3 >>> W1 >>> V2
 

MaxHeadRoom

Joined Jul 18, 2013
28,683
So I assume we have agreed this is a motor with three stator windings.
Which can alternatively be connected in either a Star or Delta configuration!??
Which from your description is currently connected in a star mode.
Pretty much what i said from the start!
Once it is permanently strapped, there is no other option at that point. :confused:
Max.
 

Thread Starter

SimpleOne

Joined Dec 22, 2014
12
So I assume we have agreed this is a motor with three stator windings.
Which can alternatively be connected in either a Star or Delta configuration!??
Which from your description is currently connected in a star mode.
Pretty much what i said from the start!
Once it is permanently strapped, there is no other option at that point. :confused:
Max.
The point is, there is nothing permanently strapped. It's just winding terminals. I could choose to permanently bridge it as star, or I could do delta, or I could do a star-delta soft start (by adding relevant contactors), and if I understand it correctly (even with just 6 wires) it could also be 2 speed with the addition of the relevant contactor, e.g.:

What I'm trying to determine, in advance, is how does one identify a consequent pole motor?
I feel as if there must be some sort of combination or permutation of measurements that make it clear if it is one, but maybe not.
 
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