Replacement 1ph motor wiring (Warco BH600)

Hi All,

I'm about to replace the single phase motor on my lathe as a temporary fix. It's like for like as far as both are dual capacitor, single phase 1400rpm, forward/reverse motors, with the exception of that the replacement motor is a little smaller, going from 2hp to 1.5hp (I already have it).

Naively, I thought it would be straightforward but I'm now not so sure. Luckily the 5 wires from the lathe are labelled (V1, V2, U1, U2, Earth) but the bit that has be confused is on the motor that was in place, all wires went to their corresponding terminals with the exception of V2 which went to Z2W2.

Further to this, the wiring from to the motor casing to the terminal block is different across the two motors...

Below is the motor wiring for the new motor - Would I be right to simply wire as it was before (I.e. lathe connects to their corresponding terminals on the motor with the exception of V2 going to Z2W2?

I did try looking in the Warco manual which was of little use and unfortunately the Grizzly manual shows different wiring compared with my machine. I've done a fair bit of googling and all examples I have come across seem to have jumpers across terminals on the motors terminal blocks whereas neither of my motors were set up like that.

Any help would be much appreciated.

Joe

That's all I ever do and I've done a few old motors now with some weird wiring

with the added caveat that I run my gear on an RCD unit, never had an issue so far touch wood

Hi Joe,

I have a BH600G. My motor has 4 wires, U1,U2,V1,V2 and the reversal is done by swapping the phase on V1,V2.
I assume the motor has an internal start switch which is not connected via the terminals.
On your motor I think what you have to do is connect the main winding to U1,U2 and the start/run winding to V1,V2. I don't know enough about terminal naming to know which terminals you need to use.

I would be interested to know if your motor has enough omph to start the lathe at high speed, I have to start the motor with the belt loose then use the belt as a clutch to spin the chuck up. I am wondering if my start cap is on the way out.

Here are my wiring diagram and motor terminals.

Thanks for the replies, I think I'm going to give it a bash.

Adrian, it does sound like your motor isn't kicking out all it's ponies. I had to replace the start capacitor when I bought the lathe (secondhand). After that, it never had a problem starting in any belt configuration 👍

Close! Had 15 minutes to nip into the garage, unfortunately it only runs forward and not reverse?

Any ideas?

I reversed a motor here without a dewhurst type arrangement

your 2 way switch needs to flip A and B via C and D

So your live/neutral wiring stay put when you switch over, and its the MOTOR wiring connections who have to trade places when you flip the switch or it doesn't work

spooky

Edited By Ady1 on 19/11/2022 23:11:39

Joe,

You need to trace out the internal circuit of your new motor. Then you can find your primary winding and the secondary/start winding etc. They need to be separated and the primary connected to U1/2 and the secondary/start etc to V1/2

Looking at your diagram in the first post this is how I think the motor is wired internally.

U1 to U2 is the main winding.

The auxiliary winding is between Z2W2 and the point where the two capacitors are connected together..(Yellow wire to the inside of the motor.

The centrifugal switch is connected between V1 and the side of the 150 uF capacitor with the black wire connected to it.

You can confirm if I am correct by doing the following resistance tests.

1 / measure the resistance between the black wire connected to the 150 uf capacitor and V1. This reading should be very close to zero ohms.

2 / Measure the resistance between U1 and U2. this should be quite a low resistance. (Less than 20 ohms,)

3 / Measure the resistance between Z2W2 and the red wire between the two capacitors.This reading should be quite low but a a bit higher in the reading from test 2

4 / measure the resistance between U1 and Z2W2 This should be a very high resistance probably more than 20 Meg ohms which is probably higher than you meter is capable of reading.

If these readings confirm my theory then connect the output from the reversing switch whose polarity is the same in forward and reverse to U1 and U2

Connect the output from the reversing switch whose polarity is reversed between the forward and and reverse positions of the switch to V1 and Z2W2.

Les.

In your post on 19/11/22 at 20:00 You do not say how you have wired the motor. If I assume that you wired it as you described in your first post with wire V2 connected to Z2W2 then I think the problem is with K2 or K3. One of the should pull in for forward and one for reverse. Does this happen ? If it does then the problem is likely to be one (Or more) of the contact sets on that contactor. If neither of these contactors pulls in for reverse Then we need to look at the control wiring feeding the coil on this contactor.

Les.