Zx45 wiring question

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J - I'm pretty sure this is it - based on everything thus far - but the legend plate is wrong (shocker) and the start cap is connected wrong.

To fix it you need to remove the blue wire from the 150UF cap off terminal ZW1 and move it to V1.

If your motor is running it will have very poor starting torque because the start cap is effectively not in the circuit at all (might be what's wrong with my own lathe).

The diagram below will provide stop (full isolate), forward and reverse off your existing switch - use the 150UF for starting in paralell with the 20UF run capacitor.
emotor6.jpg

Showing power routing in the forward position :-
emotor7.jpg

and the reverse position.
emotor8.jpg

As JB Meyer once said of a 13th century sun dial "clever these Chinese".

Regards, Ken
 
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Hi Ken, that diagram that you got of the internet is correct. The start capacitor is the higher capacitance capacitor. The start capacitor will also have a lower voltage rating than the run capacitor. If your motor is sluggish at starting you may have a faulty start capacitor or the centrifugal switch may be open circuit at the start not allowing the capacitor to be in circuit.
 
Ok, i will move 150UF cap off terminal ZW1 and move it to V1 and report back to you guys. I wanna say again how much I appreciate this and everybody's help.
This is the 1st time that the mill has been on a table and running after when I purchased it. i lifted it up to put on the table and it the strap broke and it fell 5' in hit the ground.
That's where thee original motor shaft was bent severely crack and broke some other lead screw, and other pieces and control Box, which needs to be put back together.
 
J - one last thing - check all the connections to the block - I see the block labels are in different positions to what I assumed in the earlier drawings.

My earlier drawings V2 & ZW2 must be swopped top to bottom to be physically correct - The diagrams below are exactly as per prior but with the terminals drawn as they present themselves at the motor to avoid confusion (well it confused me anyway - but that's easily done).
emotor5.jpg

Power Flow for forward
emotor9.jpg


Power Flow Reverse
emotor10.jpg

If you follow the above - the reversing switch is an isolator in the off position. Forward and reverse change the polarity of the start winding and the start capacitor boosts the start up to centrifugal switch cutout speed but the run capacitor remains engaged.
Now going by your earlier photo (and of the block on its own).

emotor12.jpg

The white wire marked V2 (currently on the top right ZW2 terminal) should be on the bottom right V2 terminal.
The 150UF start cap currently connected to the bottom left and right terminals (ZW1 & V2) should be connected to the middle left terminal (V1) and the top right terminal (ZW2)

Check your way through the entire circuit. And make sure the terminal block is as per diagram above.

Hopefully this puts this one finally to bed.

Regards, Ken
 
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Here is the orientation and nomenclature for the white block terminal
 

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J - That's how I've drawn it above - that's why I changed the diagram (but not the actual circuit) because when I flipped back through the thread I saw that very photo and realized I had misread the layout - so the most recent diagrams take that into account.
I have edited my prior posts' photo to include it side by side.
Regards - Ken
 
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emotor12.jpg

Assuming the terminal block is still wired as per photo above then.......

U1 & U2 are reversed - that is not a problem you can swop them to change forward to reverse and vice versa - leave them alone for now.

The white wire marked V2 (currently on the top right ZW2 terminal) should be on the bottom right V2 terminal.
The 150UF start cap currently connected to the bottom left and right terminals (ZW1 & V2) should be connected to the middle left terminal (V1) and the top right terminal (ZW2)

As per above swop the "start" cap brown wire with the V2 white wire from top to bottom right. Then remove the start cap blue wire (and only the start cap - leave the run cap blue wire where it is on ZW1) from bottom left terminal and move it to the left middle terminal where it will join up with the existing blue and brown (V1) wire.

Regards - Ken
 
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Ken,
This Wiring blew breaker when engaged and turn switch to the right immediately
 

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Put back to this wiring here and motor much happier forward reverse no issues no problem 4.3 amp draw on all legs
 

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J - If it's working - and that even current draw says it is - leave it alone.

Did you also previously change the switch wiring - as that may have fixed the original problem - and I just helped you to unfix it,

All's well that ends well.

I pulled out my lathe motor over the weekend and can find nothing wrong with it - I think at 550W its just simply underpowered for the machine.

I'm going to rewind it for 90V Delta three phase and run it up to 220V off a VFD at up to 120 Hz + ratio change going to get 1.4kW out of it - will post an article on that job when I'm finished.

Regards, Ken
 
Yes I have a South bend laithe that I put it in inverter duty motor on and VFD that makes it easier for reversing and hook up
 
Put back to this wiring here and motor much happier forward reverse no issues no problem 4.3 amp draw on all legs
OK, everything working good except forward in reverse is backwards.
can you suggest which wires to switch to correct?

Thank you,
John C
 
John, if you swop U1 & U2 wires around that should solve your forward / reverse problem.

You can do it at the motor - probably the easiest - or you can accomplish the same by swopping wires 10 & 12 at the switch - (terminals U1 & U2 come to at the switch in your photo - in my diagrams above it would be 7 & 10 - ignore that).

In the meantime I have rewound my single phase to three phase :-

Single Phase To Three Phase Rewind - Lathe Uprate

Regards, Ken
 
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John, if you swop U1 & U2 wires around that should solve your forward / reverse problem.

You can do it at the motor - probably the easiest - or you can accomplish the same by swopping wires 10 & 12 at the switch - (terminals U1 & U2 come to at the switch in your photo - in my diagrams above it would be 7 & 10 - ignore that).

In the meantime I have rewound my single phase to three phase :-

Single Phase To Three Phase Rewind - Lathe Uprate

Regards, Ken
Ken,
so that's what I thought I was doing it just as you sent the reply, so you rewound the motor for 3 phase instead of just doing a VFD?
 
John, You do get single phase to single phase VFD's - but I had a single phase to 3 phase to hand and I wanted to use it to crank way more power out of the existing motor. I have effectively ramped up my piddley underpowered 550W motor to 2.2kW.
You get more torque and smoother torque delivery from three phase as well.
Regards, Ken
 

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