Help with small lifting motor wiring? Where does the other end of this resistor go?

[Osteo1]

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On opening up case wire came free where does the resistor connect to? Apologies for unprofessional diagram I did it to try to understand it myself

 

[Wilko]

That looks ugly (sorry) - what's it off ?

 

[westward10]

That looks like an ad hoc addition.

 

[SparkyChick]

Looking at the length of wire that is left protruding from the end of the red sleeving on the resistor, you might get lucky and be able to identify which terminal it was connected to by looking for a piece of it in the terminal clamps. It's very short as it is and I suspect the rest of it is left in the terminal block.

I tend to agree with @westward10 though especially given the big splash of solder on the yellow jacket of the capacitor.

 

[westward10]

Nice spot SC.

 

[westward10]

Could be a discharge resistor for the capacitor but if that is a 2R2 that is an unusual resistance for that purpose.

 

[SparkyChick]

Could be a discharge resistor for the capacitor.

That was my thought as well. But if the diagram is correct, the cap would then only have one connection outside the discharge resistor. I'm also curious about the up/down switch as I don't see how you can achieve up/off/down (which I'm assuming is the operation) with only two wires.

 

[westward10]

It isn't correct that is the problem.

 

[SparkyChick]

A few more pictures of both sides of the terminal block may help, along with one looking down on the whole assembly maybe.

 

[westward10]

Op does it run without it connected. Can you show the terminal end of the capacitor.

 

[Osteo1]

It is the motor for an electric treatment plinth. motor has a worm drive to wind hydraulics up and down the switch has two buttons one makes it go up the other down. I couldnt find any residual wire in connector block unfortunately I did wonder if it was soldered to the outside of the capacitor? I also need to replace that resistor ideally as it has disintegrated a bit! The Motor works I just need to sort this switch unit

 

[Osteo1]

I haven't plugged it in to be honest just incase! The cap is sealed with just the two white wires poking out of the top so no visible connections will take a couple more photos in a bit when I get back to it

 

[Specialist]

As has already been said, it may well have been lashed in as a Bleed resistor to discharge the cap on switch off.
But you'd normally use a carbon resistor of 1 to 2 watts not a wire wound & definitely not a 2R2 more like around the 100k mark.
If it is used as a Bleed resistor then it will connect across the leads of the cap on the terminal block.

 

[westward10]

I am wondering if it was somehow used to reduce its torque but it doesn't seem man enough because assuming the drawing is correct there is no other wire connected to the capacitor possibly putting the resistor in series with the start winding??

 

[Wilko]

As a sufficient quantity of cold drink has now been consumed to make me bold, I'm going to hazard a guess :
This is a single phase induction motor with 2 windings, one start one run. The capacitor is used to create the starting field to make the rotor spin. Changing which coil has the cap connected reverses the spin. A low value R (as this seeems to be ?) can be misused in place of the C to create a lopsided field and get the rotor to start. This is just a thought and could be all rubbish

 

[Marvo]

I don't think it's a cap bleed resistor, it's the wrong type and value. It's a high power resistor that's designed to dissipate heat so it shouldn't even really be in that connection box. I'd guess it comes from either the top terminal or the third one down as you look at the photo depending on which direction you want the motor to run. I'd emphasise this is a guess so don't blame me if there's smoke....

 

[SparkyChick]

My question stands though... how can you make the motor run and change direction with only two wires to the directional switch? There appears to be a wire missing from the diagram.

 

[westward10]

As a sufficient quantity of cold drink has now been consumed to make me bold, I'm going to hazard a guess :
This is a single phase induction motor with 2 windings, one start one run. The capacitor is used to create the starting field to make the rotor spin. Changing which coil has the cap connected reverses the spin. A low value R (as this seeems to be ?) can be misused in place of the C to create a lopsided field and get the rotor to start. This is just a thought and could be all rubbish

Nearly there the start winding needs a change to reverse.

 

[westward10]

I don't think it's a cap bleed resistor, it's the wrong type and value. It's a high power resistor that's designed to dissipate heat so it shouldn't even really be in that connection box. I'd guess it comes from either the top terminal or the third one down as you look at the photo depending on which direction you want the motor to run. I'd emphasise this is a guess so don't blame me if there's smoke....

To what end. As I surmise to reduce the torque?

 

[Marvo]

We'll probably never know why but maybe torque or speed limitation. Either way that resistor is likely to get pretty warm.