Minimax CU 300 Smart electrical question

[Frank Martin]

The jointer/planer does not start when I push the start button. Instead I hear an inital light thud and then a very light whiny noise. The white light at the switch comes on too. Before this happened, I accidentally activated the micro switch at the planer dust hood. This was because I attempted to remove the hood before turning the machine off. All of the red reset buttons are at the right position. Saw function works without any issues.

It feels like I need to reset something but don't know what to reset other than the obvious red button next to each of the start switches. All those have been reset.

What am I missing?

[Frank Martin]

I found Erik Loza's following response to a similar question recently"

*************
1.) Confirm all E-stops out.
2.) Confirm selector switch in proper position, since there is often a neutral stop between funtions on the rotary switches.
3.) Confirm all saw doors/shaper doors/etc. closed and secured. There are often interlock switches there.
4.) Confirm 220-240V at the machine's terminal. Not, "I know I've got 220V", or, "the electrical dude said I have 220V". Cornfirm voltage at the terminal. Not the wal or at the socket, at the machine's terminal.

If, as the OP has reported, the main start switch feels mushy, that indicates that the coil is not being energized, which means either the machine is not getting power or that the circuit is being broken. Often, it is one of the safety interlock switches. On the CU300C, there is on that is actuated by the sawblade access door, one on the door to change the shaper speeds, and one down in the chassis, behind the jointer table hinges. That one, in my experience, is a frequent culprit, since there is a gravity-operated rod that helps disengage it when you open or close the jointer tables. OP, you can download a schematic for your machine from www.partspronto.com (http://www.partspronto.com/) and see schematics of all these switches. I have seen that drop rod get clogged with junk, moisture/corrosion make it stick, etc. Not saying that is the issue, just that of the microswitch issues, it's one of the more common ones.

**************

Based on this, most likely reason is the micro switch behind the jointer tables. However, I looked at the diagrams on partspronto but without knowing what it looks like and where exactly it is location it is hard to figure it out. Any pointers on the location would be much appreciated.

[Mike Hollingsworth]

sounds like the motor's running but you have a broken belt

[Frank Martin]

sounds like the motor's running but you have a broken belt

Belts are fine and the motor is not running. Do you happen to know where the micro switch referenced above is located?

[Erik Loza]

All the micro switches do is break the circuit that allows the machine (the entire machine, not just one function) to start. It's an on/off proposition, nothing "part way".

I agree with Mike: It sounds like a mechanical issue. I would start pulling the chassis access panels and see what's really going on in there.

Erik

[Mike Heidrick]

Is it a single or 3phase machine? Any phase converters involved. The thud is a contactor latching. Guessing there are mutiples of contactors in a saw with multiple motors.

Actuate the microswitch you triggered a couple times and try again. Make sure all estops are in their NC state (not pushed in) and that all access doors are closed.

[Frank Martin]

Thanks for the responses. I will check into the chasis to see what may be going on.

This is a single phase machine. I don't know the exact location of the micro switch to check. But, planning to do that when I figure out its location.

[Frank Martin]

I looked into the chassis to see if there was anything unusual mechanically. First, I found that there was some amount of chips/dust inside from when I had a problem with my cyclone dust collector. Cleaned it all out. There was nothing wrong visually with the jointer/planer mechanism. I could turn the motor using the belts.

The only problem I could find was that the electrical box on the saw motor was broken with the capacitors hanging down. See picture below:
340551

I did not see anything unusual with the electrical box on the jointer/planer motor. Opened the box to see if the capacitors look fine and they do. See picture below:
340552

Is it possible that somehow the capacitors in the jointer/planer motor be damaged? The symptom so far is still that when I press the on switch while in the J/P mode, I get a light thud and very light whiny noise. Saw function (despite the damaged electrical box on the motor) still works fine.

Any ideas on what could be the culprit?

[Erik Loza]

Weird on the saw area: Looks like the machine had a rough ride or something. That's a first for me.

Capacitors can be tested with a digital multi meter. There are probably a ton of videos on Youtube that describe the procedure. Please have an electrician do it if you are not comfortable dealing with stuff like this. A charged capacitor can shock you badly. Best of luck.

Erik

[Frank Martin]

Weird on the saw area: Looks like the machine had a rough ride or something. That's a first for me.

Capacitors can be tested with a digital multi meter. There are probably a ton of videos on Youtube that describe the procedure. Please have an electrician do it if you are not comfortable dealing with stuff like this. A charged capacitor can shock you badly. Best of luck.

Erik

Tested the capacitors and they are shot. One of them visibly deformed, which was not obvious while they were still in the electrical box, but once I took them out, it was pretty clear. Placed an order for the capacitors, which should arrive on Friday.

Electrical box is not something stocked, so will need to come from Italy, which may take several months. Has anyone used an aftermarket, locally available box for this?

Erik, several times I had very narrow waste from ripping get caught in the blade shroud, and I am guessing perhaps one of those somehow hit the electrical box. Inside looked very clean, so clearly something that happened recently and not long time ago while being transported.

Thanks for all the help! I will update once I install the new capacitors, to see if that solves the problem.

[Erik Loza]

Is the box damaged beyond use? I can't really tell from the photo. In other words, can you re-assemble it to get you by?

Erik

[Frank Martin]

Is the box damaged beyond use? I can't really tell from the photo. In other words, can you re-assemble it to get you by?

Erik

Sides are cracked and the screw holes for the cover are damaged. I just duck-taped it, should get me by until the part arrives...

[Erik Loza]

I recently used silicone "tape" to patch together an electrical component. It is self-adhesive and self-healing, non-conductive, and removes without residue. It also applies compression to the joint.

https://www.amazon.com/RESCUE-Self-Fusing-Silicone-Tape-Black/dp/B000ZTK6CI

Erik

[Frank Martin]

I recently used silicone "tape" to patch together an electrical component. It is self-adhesive and self-healing, non-conductive, and removes without residue. It also applies compression to the joint.

https://www.amazon.com/RESCUE-Self-Fusing-Silicone-Tape-Black/dp/B000ZTK6CI

Erik

This is a more elegant solution than the heavy duty duct tape. I will keep this in mind for future. Thanks for the tip.

[Mike Hollingsworth]

When my capacitors failed MM sent me replacements. They wouldn't fit into the original box and the new box wasn't available. Amazon had smaller ones with the same specs.
Just make sure you wait a good while until you mess with a capacitor thats been charged.

[Frank Martin]

When my capacitors failed MM sent me replacements. They wouldn't fit into the original box and the new box wasn't available. Amazon had smaller ones with the same specs.
Just make sure you wait a good while until you mess with a capacitor thats been charged.

Mike, I believe the ones I am getting are straight swaps, so I am expecting them to fit into the existing box. In any case, that is why I ordered them from Minimax as I can probably get other brands less than half the price. In fact, when I was placing the order, the Minimax person offered this option (very nice of him to let me know I can get them cheaper elsewhere), but I still went with them to make sure they fit into the box.

About waiting, not sure what you mean, as long as I discharge them (by connecting the two terminals), is there a reason to be worried about this? I did this before wit another motor on a different machine (thankfully no longer own that machine) and did not have any issues

[Mike Hollingsworth]

Mike, I believe the ones I am getting are straight swaps, so I am expecting them to fit into the existing box.

You'd think. But mine didn't.





About waiting, not sure what you mean, as long as I discharge them (by connecting the two terminals), is there a reason to be worried about this?

No guarantees, but I guess they'd be safe after discharge.
Any electricians here?

[Mike Heidrick]

You use a "bleeder" resistor to bleed a start capacitor. Measure it with a meter to make sure it is fully discharged. Just waiting will not discharge a cap. Also do not just short them.

https://www.youtube.com/watch?v=9xzvfsaGKKw

[Frank Martin]

You'd think. But mine didn't.


You were right! The package arrived and the new capacitors are larger and would not fit into the existing box. Disappointing given the only reason I ordered from Minimax was to make sure it is straight swap, which I had mentioned to the person while I was placing the order. Anyway... So, how did you install your capacitors, did you use any bracket, etc.? Do you have any pictures?

[Jim Becker]

They may not be able to get the "original" caps currently...that might account for the size difference. Bummer that you have to deal with that, but hopefully, you'll have things back up and running once you figure the best way to protect them. (Perhaps a second box?)

[Frank Martin]

I have installed the 60 uF capacitor and still have the same symptoms. The other, 70 uF capacitor, is fine and tested exactly where it should be and visually looks good. So, back to square one. What else could be wrong?

Erik, I know you had said the micro switch tied to the planer hood cannot be the problem because it would not let other functions operate, but I still would like to check to make sure it looks okay. Can you please point me to its location, I could not locate it.

Regarding the second box for the new larger capacitor, I will order a project box from Amazon as I could not find it at the big box store.

[Mike Hollingsworth]

You were right! The package arrived and the new capacitors are larger and would not fit into the existing box.

Got mine from Amazon.

I believe that the start was 60
The run was 70.

Or was it the other way around?

Anyway, they're a fraction of the cost of the ones that we got from SCMI.

[Frank Martin]

Got mine from Amazon.

I believe that the start was 60
The run was 70.

Or was it the other way around?

Anyway, they're a fraction of the cost of the ones that we got from SCMI.

Mike, did the ones from Amazon fit into the existing box? If so, do you happen to have the link to the ones you ordered. You are definitely right about the Amazon price being a fraction, the 70 uF is about a third of the SCMI price. Would have been okay if it were a straight swap to avoid the pain but not the case...

Looks like I have another problem beyond the capacitors, so back to square one...

[Erik Loza]

Frank, the parts manual for the machine (if you don't have it, you can download it from partspronto.com) shows the locations of the various micro-switches. Again, the switches are an on-off proposition: If any function on the machine starts, then it's not one of the switches. The switches, any of the switches, kills power to the entire machine. Assumimg the new capacitors are correct and didn't start the motor and assuming there is nothing mechanical obstructing the cutterhead from turning, my next step would be to pull the motor in question and have it tested by a motor shop. Best of luck with it.

Erik

Oh, by the way, I would call Martin ot woever you dealt with and and see about returning those capacitors. Just tell them they won't physically fit the enclosure. I wondered about the size thing, myself. Actually did not realize SCM sold just the capacitors. The whole motors, yes, but not just the caps. Most of my guys have, as Mike is talking about, just sourced them locally or online. Generally, they call out the physical dimensions of the cap. in the supporting info. I bought some at thelocal Grainger once. Sorry I did not step in this sooner: Been traveling the last few days.

[Frank Martin]

Frank, the parts manual for the machine (if you don't have it, you can download it from partspronto.com) shows the locations of the various micro-switches. Again, the switches are an on-off proposition: If any function on the machine starts, then it's not one of the switches. The switches, any of the switches, kills power to the entire machine. Assumimg the new capacitors are correct and didn't start the motor and assuming there is nothing mechanical obstructing the cutterhead from turning, my next step would be to pull the motor in question and have it tested by a motor shop. Best of luck with it.

Erik

Oh, by the way, I would call Martin ot woever you dealt with and and see about returning those capacitors. Just tell them they won't physically fit the enclosure. I wondered about the size thing, myself. Actually did not realize SCM sold just the capacitors. The whole motors, yes, but not just the caps. Most of my guys have, as Mike is talking about, just sourced them locally or online. Generally, they call out the physical dimensions of the cap. in the supporting info. I bought some at thelocal Grainger once. Sorry I did not step in this sooner: Been traveling the last few days.

Erik,

I will test everything once last time and then take it to a motor shop. It looks like to remove the J/P motor I need to first remove the shaper motor.

About returning the capacitors, I think Martin was just trying to help me. He did tell me that I can buy those from many other sources at a cheaper price. I went with SCMI just to make sure they fit into the box. However, from our conversations about the electrical box on the saw motor, I realize some of these electrical components do change over time, which looks like is the case in my situation. I will call Martin about returning these and look into getting the right size capacitor.

One question about the capacitor spec, in addition to the microfarad rating, there are voltage ratings on the original ones showing three values such as 500V, 450V, 400V and next to each 25/085/21. Given my machine is 220 V, other than matching the microfarad rating, making sure they are rated for at least 220V and the size match do I need to worry about anything else? Do you have any links to the those available online?

Thanks for the help, really appreciate your support!

[Mike Hollingsworth]

Frank

For the life of me I can't find my Amazon order.
I will send a photo of the actual unit when I return home tomorrow.

It is smaller than the original cap, fits fine.
I've found that most 4.7 hp single phase from MM use the same caps.

The capacitors that they are sending out are useless.
MM should get their act together.

[Frank Martin]

Frank

For the life of me I can't find my Amazon order.
I will send a photo of the actual unit when I return home tomorrow.

It is smaller than the original cap, fits fine.
I've found that most 4.7 hp single phase from MM use the same caps.

The capacitors that they are sending out are useless.
MM should get their act together.

Mike, that would be very helpful! I checked on Amazon and the ones I think would fit are not small enough. Thanks!

[Frank Martin]

I think I may be closer to the root cause of the problem. I removed the J/P motor based on Erik's recommendation with the plan to take to a motor shop. Once I got it out I direct wired it to make sure the problem is really with the motor. It was not. It started just fine, multiple times.

Here are some other facts:

* I checked the leads that normally go the J/P motor (while the motor is out), one of the hot leads read the expected 120V the other one was only showing 37V.

* When the main function selector switch is at the J/P mode and I hit the power button, I still get the light thud, the whiny noise and the white light between the on (I) and off (0) button on the main power switch comes on. So, these noises are coming from the main switch area, not from the motor.

* I get the same light thud, the whiny noise and the white light when the switch is at one of the 0 (zero) positions between each function on the rotary selection switch and I hit the power button.

So, it must be either the rotary function selector switch, a fuse, or some other electrical component. What do you think may be the root cause and how can I check it?

[Jim Becker]

Frank, you may be onto something. I did have to replace the rotary switch on my FS-350 J/P a number of years ago when it failed prematurely.

[Mike Hollingsworth]

Here's the replacement I got from Amazon.
Can you believe it? Something made in the USA.

Google the numbers on the switch.
Lots of suppliers for MM parts. Most from Siemens.

340933

[Mike Hollingsworth]

Frank

I know a really good repair guy if this continues to boggle.

[Frank Martin]

Here's the replacement I got from Amazon.
Can you believe it? Something made in the USA.

Google the numbers on the switch.
Lots of suppliers for MM parts. Most from Siemens.

340933

Mike, thanks so much for going through the trouble to get the capacitor out and take the picture. This is even smaller than the original one and should fit in the box perfectly.

[Frank Martin]

Frank

I know a really good repair guy if this continues to boggle.

Mike, I will wait for Erik to chime in and like Jim, I am suspecting it may be the switch. In any case, please pm me your guy's info. I would rather spend my very limited time woodworking instead of machine repair. Thanks!

[Frank Martin]

Frank, you may be onto something. I did have to replace the rotary switch on my FS-350 J/P a number of years ago when it failed prematurely.

Jim, I am also suspecting this may be the case and hoping Erik can chime in and shed some light. Did you have the same noise symptoms on your switch when yours broke?

[Frank Martin]

I have finally fixed the jointer / planer motor, so wanted to provide an update in case anyone has a similar problem in the future.

As I suspected, in addition to the capacitor, the main rotary switch (used to select different functions) was broken. So, I ordered the part through SCM, which took 3 weeks to arrive from Italy. Unfortunately, the part that came in was not a direct replacement to the original one. Although, the new switch looks a lot better made. Someone at the SCM technical service provided a wiring diagram for the new switch. It was for a 3-phase machine and mine is 1-phase. I did some testing with the multimeter and figured out the correct configuration. Installed everything back and it works fine now.

Now, I have a new problem that I did not have before. The shaper motor is a lot noisier then before. I know it is the motor and not the rest of the spindle assembly because I tested to make sure. It was not like that before. So, I need to check into that but that can wait for now as I don't need the shaper for my current project. If anyone has any pointers on what to look for I would appreciate. I plan to check the fan to make sure it is freely rotating as I remember hearing that to be a somewhat common problem. I am guessing with uninstall and reinstall the fan may have dislocated. There is no damage to the outside and I set it on foam board during removal. Perhaps just a coincidence, but I definitely did not mishandle the motor during this process.

One of the most painful part of this process was removing and reinstalling the jointer / planer and the shaper motors. The motors are heavy and accessing through the small shaper door made it less than easy. This is clearly one of the compromises of a combination machine, fitting a lot of functionality into a small footprint. I hope I don't have to do this again anytime soon (other than fixing the shaper motor of course!).

Thanks again to all for helping me with this. Great to have this machine up and running again.