LumberJocks

Planer magnetic switch broken

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by giser3546 posted 12-27-2015 12:23 AM 1018 views 0 times favorited 38 replies Add to Favorites Watch
View giser3546's profile

giser3546

179 posts in 937 days


12-27-2015 12:23 AM

I have a 220V Sunhill 20” planer with a mag switch that has just stopped working. I’ve used a no contact voltage detector to verify that voltage is making it to the switch but not beyond it. Nothing happens when I hit the on button no click or anything. I have experience with electrical and electronics work but have no idea what I’m looking at. I’ve heard these kinds of switches commonly require ”... the contacts to be cleaned” but I have no idea how to go about doing that. Anyone have any experience with this kind of thing?

-- "If you wait for it to rain, It will"


38 replies so far

View lew's profile

lew

11340 posts in 3220 days


#1 posted 12-27-2015 01:53 AM

Not sure what’s wrong, but if you need to replace it, check with Grizzly.

Some of those switches have a thermal overload protection. Maybe it needs reset.

-- Lew- Time traveler. Purveyor of the Universe's finest custom rolling pins.

View sawdustdad's profile

sawdustdad

131 posts in 349 days


#2 posted 12-27-2015 01:55 AM

I’ve had trouble with grizzly’s magnetic switches. I replaced the one on my 20 inch planer twice then finally broke down and installed a 240v double pole circuit breaker in a small box. It’s a simple switch in this configuration, so the planer will restart on a return from loss of power, so be aware of that.

-- Murphy's Carpentry Corollary #3: Any board cut to length has a 50% probability of being too short.

View Quanter50's profile

Quanter50

273 posts in 1760 days


#3 posted 12-27-2015 02:12 AM

View giser3546's profile

giser3546

179 posts in 937 days


#4 posted 12-27-2015 02:17 AM

I’m thinking if the switch needs to be replaced I will go with a non magnetic replacement. The $70 to $90 price doesn’t seem worth the advantages of the mag switch given that I’m the only one ever in my shop let alone using my biggest piece of equipment.

-- "If you wait for it to rain, It will"

View TopamaxSurvivor's profile

TopamaxSurvivor

17671 posts in 3140 days


#5 posted 12-27-2015 07:15 AM



I ve had trouble with grizzly s magnetic switches. I replaced the one on my 20 inch planer twice then finally broke down and installed a 240v double pole circuit breaker in a small box. It s a simple switch in this configuration, so the planer will restart on a return from loss of power, so be aware of that.

- sawdustdad


The circuit breaker does not provide overload protection for the motor.

From what I can see, that may be a manually operated switch. Not enough info to even make a bad guess at the issue causing the failure.

-- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence

View Tennessee's profile

Tennessee

2410 posts in 1979 days


#6 posted 12-27-2015 02:08 PM

Normally, when you hit the green button, it energizes the coil, which pulls in the contactor and a latching circuit takes over and keeps the coil energized and the contacts engages. The click you hear is the contacts hitting home. With no click, no coil is being energized, so no contact engagement. When you hit the red button, you interrupt the coil circuit, allowing the contacts to spring away from each other and stop the unit.

Either you have a burned out coil, the overload (sometimes called a heater) is open and not allowing the coil to energize, or you have a loose wire.

Overloads can be reset. Sometimes overloads also burn out. A burnt coil may or may not be enough to replace the switch.

If you feel comfortable, you can read the coil continuity out with a multimeter to see if it is burnt and open. If it is OK then the overload is probably open. Wire coming off is doubtful, but check inside.

-- Paul, Tennessee, http://www.tsunamiguitars.com

View TopamaxSurvivor's profile

TopamaxSurvivor

17671 posts in 3140 days


#7 posted 12-28-2015 01:01 AM

Obviously those red and green buttons on the cover were not wired to the contactor. I don’t see any wires on the terminals of what looks like the auxiliary contacts. That is what makes me believe it is a manually operated contactor. The red button would be a combo stop and reset.

-- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence

View sawdustdad's profile

sawdustdad

131 posts in 349 days


#8 posted 12-28-2015 02:36 AM



The circuit breaker does not provide overload protection for the motor.
- TopamaxSurvivor

100% correct. But motor is a TEFC with thermal overload protection. So there is a trade off. The hassle of failing magnetic starters vs a reliable on-off switch.

-- Murphy's Carpentry Corollary #3: Any board cut to length has a 50% probability of being too short.

View TopamaxSurvivor's profile

TopamaxSurvivor

17671 posts in 3140 days


#9 posted 12-28-2015 04:11 AM


The circuit breaker does not provide overload protection for the motor.
- TopamaxSurvivor

100% correct. But motor is a TEFC with thermal overload protection. So there is a trade off. The hassle of failing magnetic starters vs a reliable on-off switch.

- sawdustdad

It is too bad that the US allowed the international motor starters. A NEMA control relay has better contacts than those motor starters. NEMA motor starters are permanent not a temporary installation. Of course, allowing that international garbage is a full employment act for those of us who know how to troubleshoot and repair ;-)

-- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence

View Tennessee's profile

Tennessee

2410 posts in 1979 days


#10 posted 12-28-2015 01:31 PM

So the start button is the black button to the right of the main coil. The overload protector would be the green dial next to the red button, and the red square button would be the stop button that would interrupt the coil circuit. It would also serve as the reset button for the overloads. If the motor also has thermal overload, it is totally internal to the motor with automatic reset, or is there a reset button on an end bell of the motor? (Probably not)

Obviously the one in the contactor is strictly an amperage overload.

-- Paul, Tennessee, http://www.tsunamiguitars.com

View giser3546's profile

giser3546

179 posts in 937 days


#11 posted 12-28-2015 07:05 PM

I appreciate the help guys but am still a little lost on what to do next. I have a multi meter but feel like I need to know more about this thing before unhooking connections. I’m looking for a wiring diagram to try to get an idea of whats what in this thing but nothing seems too helpful.

I was doing some electrical work and shut off the power to my shop, when I turned it back on the switch was bad. I didn’t shut off during use or anything.

-- "If you wait for it to rain, It will"

View pintodeluxe's profile

pintodeluxe

4856 posts in 2277 days


#12 posted 12-28-2015 08:17 PM

Is the green circle with a straight screwdriver slot actually a fuse holder? If you don’t find a re-settable overload switch, then I would look for a fuse before replacing the whole mag switch.

-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush

View giser3546's profile

giser3546

179 posts in 937 days


#13 posted 12-28-2015 09:15 PM

The reset switch is hit when the off button is hit, I’ve also tried it manually. I think the green circle is an amperage selector.

-- "If you wait for it to rain, It will"

View TopamaxSurvivor's profile

TopamaxSurvivor

17671 posts in 3140 days


#14 posted 12-29-2015 07:26 AM

The green circle sets the amp trip point. Now that you have a meter, it should be relatively simple to determine the problem. Do you have power in? Push the on button. Do you have power out? If not, firmly press the reset, you may feel it click. Check the power out again. Is it manually held? I don’t see enough wires in your pictures for it to be magnetic. Good luck.

-- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence

View giser3546's profile

giser3546

179 posts in 937 days


#15 posted 12-29-2015 02:33 PM

Did some digging and found this:

After work today I am going to get my multi meter out and test to see if its the “Contactor” or the “Overload Relay” that needs to be replaced. Assuming its one or the other that is bad could I replace just the contactor? I don’t see the relay on the grizzly site, any idea where I could get one if thats the issue? I’m also wondering which leads to test?

-- "If you wait for it to rain, It will"

showing 1 through 15 of 38 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com