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 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:
IMG_1838.jpg

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:
IMG_1841.jpg

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-F.../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-F.../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.