Capacitor ?

[Ralph Okonieski]

Will you educate me on capacitors, please?

The motor on my saw hummed and would not turn under load. It did turn without belt attached. I called SCM service and talked with technician. Kudos to them, they called me an hour after I had submitted my support request. Diagnosis is to replace the capacitor. There only appears to be only one capacitor which was located outside the motor. I opened the box on the motor and only see wires, nothing else that looks like a capacitor. I plan to contact SCM on Monday for a replacement but am hedging my bets in case I need to replace with an aftermarket. I searched online for comparable but nothing matched exactly. Motor is 240v single phase. Capacitor has two wires coming out of it into the electric box on the motor. It is 1.75 inches in diameter and 4 inches long. The machine is a Minimax c26 genius multi-function machine, having three separate motors. So, my questions are:

- can only one capacitor act as both start and run capacitor?
- There are two voltages listed on the label (400v and 450v). Does the capacitor need to have those exact voltages or would 450v be sufficient.
- It is going to be a real challenge to get into the electric box because of the tight space, so I would like to cut the wires near the capacitor and just splice wires to the new one (when it comes). Any issue with doing this?
- other threads on this forum discussing capacitors indicated that one could go a little higher in micro farads. This one is 35uf, so how high could it go and still be a good replacement? Is that what +5% indicates?
- anything else to be aware of?

Thanks in advance,

Ralph

[Josh Molaver]

I can't answer all your questions, but this appears to be an exact replacement: https://www.buyspares.com/motor-capacitor-sintex-35uf/product.pl?pid=5144284 for $20

You can cut the wires and splice them but the splices should be in a box, not exposed.

[Rod Sheridan]

Will you educate me on capacitors, please?

The motor on my saw hummed and would not turn under load. It did turn without belt attached. I called SCM service and talked with technician. Kudos to them, they called me an hour after I had submitted my support request. Diagnosis is to replace the capacitor. There only appears to be only one capacitor which was located outside the motor. I opened the box on the motor and only see wires, nothing else that looks like a capacitor. I plan to contact SCM on Monday for a replacement but am hedging my bets in case I need to replace with an aftermarket. I searched online for comparable but nothing matched exactly. Motor is 240v single phase. Capacitor has two wires coming out of it into the electric box on the motor. It is 1.75 inches in diameter and 4 inches long. The machine is a Minimax c26 genius multi-function machine, having three separate motors. So, my questions are:

- can only one capacitor act as both start and run capacitor?
- There are two voltages listed on the label (400v and 450v). Does the capacitor need to have those exact voltages or would 450v be sufficient.
- It is going to be a real challenge to get into the electric box because of the tight space, so I would like to cut the wires near the capacitor and just splice wires to the new one (when it comes). Any issue with doing this?
- other threads on this forum discussing capacitors indicated that one could go a little higher in micro farads. This one is 35uf, so how high could it go and still be a good replacement? Is that what +5% indicates?
- anything else to be aware of?

Thanks in advance,

Ralph

Hi, at 35uF that’s most likely the run capacitor, that’s why the motor can start under no load.

Check inside the control panel or inside the machine cabinet for additional capacitors.

There should be another capacitor to start the motor, do not change the value of the run capacitor.

Regards, Rod.

[Ralph Okonieski]

Thank you, Josh and Rod. I appreciate your help.

[Rod Sheridan]

You’re welcome.

Do you have a schematic for your machine?

If so please post a copy of it here.

Regards, Rod

[Ralph Okonieski]

Rod, Here are the schematics. There are more in the manual but think these three are the appropriate ones.

473871 473872 473873

[Rod Sheridan]

Thanks Ralph, as there are only 2 wires going to the motor I learned 2 things

1) your shaper doesn't have reverse

2) all the capacitors are local to the motors (on many multifunction machines the 2 capacitors are shared by all the motors)

I expect that the motors have a centrifugal starting switch which may be the problem with your saw motor.......Regards, Rod.

[Ralph Okonieski]

Rod, as far as I can see, there is only one capacitor on each of the three motors. There are no other cylindrical or oval cylindrical components that look like they might be another capacitor. From what I’ve read from various sites (yeah, I know can’t believe everything on the internet), some capacitors act as both start and run. So, my plan at this time is to find a suitable replacement for it.

I’ve never used the shaper and have no tooling for it although some day may.

thanks for your insight.

This is the plaque on the motor.
473938

[Myles Moran]

- can only one capacitor act as both start and run capacitor?

Yes, but it'd have 3 wires, not 2. Not all motors need a start and a run. Some use both, some use a start, and some have a permanently connected capacitor.

- There are two voltages listed on the label (400v and 450v). Does the capacitor need to have those exact voltages or would 450v be sufficient.

That i don't know for sure, but I'd error on the side of caution


- It is going to be a real challenge to get into the electric box because of the tight space, so I would like to cut the wires near the capacitor and just splice wires to the new one (when it comes). Any issue with doing this?

As long as it fits i don't see why not. Most are connected with spade terminals, so if you have the means to crimp one on, that's what I'd do.

- other threads on this forum discussing capacitors indicated that one could go a little higher in micro farads. This one is 35uf, so how high could it go and still be a good replacement? Is that what +5% indicates?

The +/-5% is the tolerance in the capacitance of the capacitor. So if it's within 5% of the listed value it's in spec.

- anything else to be aware of?

Not sure where you're ordering from, but I've had good luck buying from Grainger, at least for having a spare A/C capacitor on hand. Got it the same day via order pickup, so no waiting on shipping.

[Rod Sheridan]

Hi, still looks like a failed start switch to me……Rod

[Ralph Okonieski]

Just a follow up to close down this question that I originally posed.

My saw is now running fine. The run capacitor (only capacitor visible that I can find) was replaced. The failed capacitor was bulging and had actually “popped” one end cap. I tried to source a replacement from SCM because it is a MiniMax machine, but they did not have a replacement. I’ve lost some faith in SCM for not having or being able to source a replacement for such a common maintenance item.

My thanks to everyone that provided information related to my questions. I felt quite confident going into the actual repair; it was quite straightforward. Knowledge is powerful.

Ralph