Zx45 wiring question

[Ken I]

J - This is how I see it wired up (complying with the motor's label) :-

It appears the original jumpers were correct.

This is what happens :-

U1U2 appears to be the run winding and is always switched on with the same phasing when running.
V1V2 is the start winding,
You will notice the start coil (V1V2) coil is reversed (with respect to phasing) when starting the other way. This coil is turned off by the cenrifugal switch once the motor is up to speed (70-80% thereof-ish)
(I have used red for live and blue for neutral to show phasing rather than preferred connection - it doesn't actually matter which is which).
I presume the bigger capacitor is the start capacitor.
The smaller capacitor - I suspect - is simply to drain down auto-induced voltages in the start winding - which it does in series with the larger capacitor once the centrifugal switch has opened - which I would presume is of some benefit to performance as well.

Since the smaller capacitor is hard on to the mains when starting - it might serve as a power factor correction capacitor to reduce demand during starting.

Other than that, I can't see what it does.

It's definitely incorrectly connected in the earlier photo you supplied - across the start switch.

I think your problem is partly due to the label diagram - though diagrammatically correct - does not correspond to the physical layout of the terminals.

Hope all this helps.

Regards - Ken

 

[Claudio Masetto]

Hi, I have attached a drawing showing how to connect your reversing switch. Note that U2 is permanently connected to the neutral terminal. The wires that cross do not connect. This will work provided that the wires going to the terminal block of the motor are connected as the photo shows in your number 15 post. As you can see the main winding U1 & U2 do not reverse but the auxilary winding V1 & V2 with both capacitors is reversed in respect to the main winding.
Ken, your wiring diagram does not allow for the smaller capacitor ( the run Capacitor) to remain in series with the auxilary winding. This capacitor gives the motor extra torque when it is running. Without it the motor will not develop its full power.

 

[Ken I]

Claudio - keeping the capacitor on the auxiliary winding totally negates the need for a centrifugal switch - other than to remove the bigger one once the motor is started (a possibility - but not one I'm familiar with)

The problem with running both windings is resultant phase angle between them which is load dependent - so typically used to drive pumps, compressors etc with pretty constant loading (even if it is intermittent).

For what might be sustained loads at almost any value the auxiliary winding is switched out - less torque to be sure - but also less heating due to parasitic currents caused by out of phase windings - effectively fighting each other (other than at whatever nominal output is correct).

Having said that - you could well be right. However guided by the switch and motor label, I think I'm correct. The switch configuration indicates to me its intention is to be an isolator in the off position - your set up isn't.

Your set-up will give more torque but also more heat and less efficiency (probably at the low end) - maybe J wants to try both set-ups.

Regards, Ken

 

[jcollings]

Run capacitor is on the left, Rin

capacitor is on the left

 

[jcollings]

Start capacitor is on the right

 

[jcollings]

J - This is how I see it wired up (complying with the motor's label) :-
View attachment 119398
It appears the original jumpers were correct.

This is what happens :-
View attachment 119399
U1U2 appears to be the run winding and is always switched on with the same phasing when running.
V1V2 is the start winding,
You will notice the start coil (V1V2) coil is reversed (with respect to phasing) when starting the other way. This coil is turned off by the cenrifugal switch once the motor is up to speed (70-80% thereof-ish)
(I have used red for live and blue for neutral to show phasing rather than preferred connection - it doesn't actually matter which is which).
I presume the bigger capacitor is the start capacitor.
The smaller capacitor - I suspect - is simply to drain down auto-induced voltages in the start winding - which it does in series with the larger capacitor once the centrifugal switch has opened - which I would presume is of some benefit to performance as well.

Since the smaller capacitor is hard on to the mains when starting - it might serve as a power factor correction capacitor to reduce demand during starting.

Other than that, I can't see what it does.

It's definitely incorrectly connected in the earlier photo you supplied - across the start switch.

I think your problem is partly due to the label diagram - though diagrammatically correct - does not correspond to the physical layout of the terminals.

Hope all this helps.

Regards - Ken

So you're saying install these jumpers on the below statement I made earlier before trying to fire it up?

"Originally this switch also had jumpers from 9 and 12 and 8 and 11 according to my numbering diagram."

 

[Ken I]

At your motor - the white wire labled V2 should be on ZW2 and the brown cap wire on ZW2 should be on V2 (ie swop them) to comply with the legend plate (It still feed V2 but via the cap).

Now as you have the caps the other way around to my diagram - it may be that is the way - it will work with the caps swopped - I'm just not sure which will be better. Try it with the caps either way around. The way around that starts quickest is correct (most torque / acceleration).
did the motor come with those caps assembled as they are ?

And Claudio's method may be more correct than mine.

Mine is the way the motor legend plate shows it - but the legend plate does not indicate which cap is the 150 and which cap is the 20.

Terminal connections at switch :-

White on to 9 + jumper to 12
Brown onto 8 + Jumper to 11
Black onto 10
Red on to 7

Live on to 4
Neutral on to 1

No other jumpers.

Did the kit come with those labels on the wires ? (unfortunately it doesn't mean it's correct as the cable may be for more than one kit and they don't bother).
Regards, Ken

 

[Claudio Masetto]

Hi Ken, this type of motor is called a capacitor start capacitor run motor. The larger starting capacitor cannot be kept energised for very long but it provides the motor with a large starting torque until the centrifugal switch picks up speed and cuts this capacitor out of the starting circuit.
The smaller value run capacitor is designed to remain in the starting circuit and provide the motor with extra torque. Manufactures use this method these days to enable a larger horsepower to be obtained from a smaller frame. 75% of the single phase motors produced these days use this method.
Jcollings reversing switch is a 3 pole changeover switch. This is a common setup on a Chinese single phase motor which is used for reversing.
This is why one side of the main winding is connected to the Neutral permanently. There are not enough poles on that switch. A proper single phase reversing switch is a 4 pole changeover switch. The Chinese do this because of cost. They use a 3 phase switch which they have plenty of.

 

[jcollings]

Excellent ! when I hook it up and test it I will be back with you on results.
All your help is Greatly appreciated.

Thank you!

 

[jcollings]

At your motor - the white wire labled V2 should be on ZW2 and the brown cap wire on ZW2 should be on V2 (ie swop them) to comply with the legend plate.

Now as you have the caps the other way around to my diagram - it may be that is the way - it will work with the caps swopped - I'm just not sure which will be better. Try it with the caps either way around. The way around that starts quickest is correct (most torque / acceleration).
did the motor come with those caps assembled as they are ?

And Claudio's method may be more correct than mine.

Mine is the way the motor legend plate shows it - but the legend plate does not indicate which cap is the 150 and which cap is the 20.

Terminal connections at switch :-

White on to 9 + jumper to 12
Brown onto 8 + Jumper to 11
Black onto 10
Red on to 7

Did the kit come with those labels on the wires ? (unfortunately it doesn't mean it's correct as the cable may be for more than one kit and they don't bother).
Regards, Ken

All the wire labeling and switch numbering that is on the switch was factory when received for the original 110 set up.
The only numbering that is different is from the diagram that I posted with my numbering just for convenience for me to understand better.

 

[Ken I]

Claudio, Thanks for your input - certainly confusing clues given by the switch used and poor plate illustration - so you are probably correct - I'm certainly not terribly familiar with this type of set up although my own Chinese lathe has a dual cap set up and the starting torque is awful - I've never pulled it apart - I now think that is something I should do - I was going to rewind and install a VFD - but I'll check out what the idiots have done first.
Regards - Ken

 

[jcollings]

Hi Ken, this type of motor is called a capacitor start capacitor run motor. The larger starting capacitor cannot be kept energised for very long but it provides the motor with a large starting torque until the centrifugal switch picks up speed and cuts this capacitor out of the starting circuit.
The smaller value run capacitor is designed to remain in the starting circuit and provide the motor with extra torque. Manufactures use this method these days to enable a larger horsepower to be obtained from a smaller frame. 75% of the single phase motors produced these days use this method.
Jcollings reversing switch is a 3 pole changeover switch. This is a common setup on a Chinese single phase motor which is used for reversing.
This is why one side of the main winding is connected to the Neutral permanently. There are not enough poles on that switch. A proper single phase reversing switch is a 4 pole changeover switch. The Chinese do this because of cost. They use a 3 phase switch which they have plenty of.

So you're saying a regular drum switch example furnas R44 or square D. 2601 type would be more appropriate?

 

[Claudio Masetto]

Hi J, a word of caution and advice. Even though the switch is in the OFF position and the motor is not running, one side of the supply will still remain connected to the motor. This is dangerous and if any electrical work is to be done on the motor the machine must be unplugged from the supply. I'm sure that this setup does not comply with your Electrical Codes.
You should consider installing a proper 4 pole single phase reversing switch. This way, when the switch is in the OFF position the motor will be isolated from both sides of the supply.
Unfortunately the Chinese pay little attention to safety and wiring codes and we find that a lot of machinery that comes from China has to be rewired to meet our Electrical Codes.
I am not familiar with the two types of drum switches which you have described.
Ken, you should not have poor starting torque with a dual capacitor motor. Maybe your start capacitor is faulty or it is not wired correctly in the starting circuit.

 

[jcollings]

Claudio,
Please review this paperwork insert for a selection of different scenarios for an AR14 switch, Do any of these sequence meet what you described.

 

[jcollings]

At your motor - the white wire labled V2 should be on ZW2 and the brown cap wire on ZW2 should be on V2 (ie swop them) to comply with the legend plate (It still feed V2 but via the cap).

Now as you have the caps the other way around to my diagram - it may be that is the way - it will work with the caps swopped - I'm just not sure which will be better. Try it with the caps either way around. The way around that starts quickest is correct (most torque / acceleration).
did the motor come with those caps assembled as they are ?

And Claudio's method may be more correct than mine.

Mine is the way the motor legend plate shows it - but the legend plate does not indicate which cap is the 150 and which cap is the 20.

Terminal connections at switch :-

White on to 9 + jumper to 12
Brown onto 8 + Jumper to 11
Black onto 10
Red on to 7

Live on to 4
Neutral on to 1

No other jumpers.

Did the kit come with those labels on the wires ? (unfortunately it doesn't mean it's correct as the cable may be for more than one kit and they don't bother).
Regards, Ken

When the motor was sent to me that's where the Were positioned V-1 Z1W1 and V-2 terminal on motor white block

 

[jcollings]

Ok, Running in both directions.
One leg amps 4.2 and 4.4
Other leg 4.2. 4.4
Those values for forward and reverse.
See pictures as to how wires are landed

 

[Claudio Masetto]

What's your connections on the other side of the switch?

 

[jcollings]

 

[jcollings]

Post 17 a picture might be clearer

 

[Ken I]

J - re: your prior post - is it now working wired as per photos ?
Regardless of anything else - that 150UF cap connected across ZW1/ZW2 (Centrifugal switch ?) goes nowhere and the centrifugal switch would be shorting out a non-functioning capacitor.
Makes no sense at all.
Unless.....
There are some links to the windings below the terminal block to the windings - or a jumper is missing - or ZW1/ZW2 is something else.... whatever..... something wrong right there.
But if it's working - put the covers back on and open a frosty.

(Image off internet - caps incorrectly drawn as electrolytics)

Claudio - I presume this is the set up ?

Start capacitor in parallel with run capacitor until switched out by the centrifugal switch - I would have thought the start capacitor would be the bigger value ?

I see in J's photo the 20UF is physically larger than the 150UF - presumably because being the run capacitor it has a higher continuous kVAr rating whereas the start capacitor is for intermittent duty.

The photos still don't make sense nonetheless.

Regards, Ken