UPATED WITH PICTURES Help!! Lightning does and did strike twice.

[ScottM]

A few weeks back I posted that we had a lightning strike so close it knocked pictures off the wall and blew out the metal crawl space hatches out. A week and half ago lightning struck a large white oak about 30 feet from my shop. One 240 circuit breaker popped in my shop as the result. Any way I went out to the shop and trying to use my SuperMax 19-38 drum sander. The drum turned on but when I turned the belt drive on, I heard a pop like a breaker popping and nothing. The sound came from the sander. Per the SuperMax site there are not fuses or circuit breakers built into the machine. I have removed all the screws except the two on the top, they just spin, and control box does not open. SuperMax does sell a replacement switch/control box/motor assembly which is very pricey but even if I went that route, I can't see how to remove the old one. I checked YouTube but could not find any videos. This is a $2k machine which I use regularly so I am willing to pay to get it fixed.

 

[bowman]

It looks like the switchbox slides off after removing the 2 front facing screws and the 1 screw above the motor. I'm assuming you tried that?

 

[ScottM]

It looks like the switchbox slides off after removing the 2 front facing screws and the 1 screw above the motor. I'm assuming you tried that?

Correct

 

[CharlieGator]

Would you take a couple more pictures from other sides? That might help.

 

[kserdar]

Conveyor And Motor Diagram - SuperMax 19-38 Owner's Manual [Page 28]

SuperMax 19-38 Manual Online: Conveyor And Motor Diagram. 19-38 DRUM SANDER OWNER'S MANUAL Technical Specifications 28...

www.manualslib.com

 

[wndopdlr]

It is too late for the most recent events, but I offer the following for the future. When I bought my Robust AB lathe, I was concerned about the same thing you are experiencing because I, too, have experienced lightning damage. I had an electrician wire whole house surge protectors into my service panel. If I remember correctly it was in the $200 range, but I no longer fear thunderstorms.

 

[ssmith]

+1 on more pictures. Maybe the motor is mounted to the control box and has to be removed before the control box can be opened?

The schematic doesn't show enough detail, but DC motors don't run directly off AC so there's definitely electronics in the controller. Usually, they're the weak point with line transients so the motor may be OK.

 

[mdbuntyn]

Using the schematic that Ken linked to I found a link for the control board (16-32, 19-38, 25-50 Drum Sander Intellisand Control Board - Laguna Tools Parts & Accessories). Those top two screws go into posts/stand-offs in the control board, and the posts are probably spinning in their mounting holes.

 

[ScottM]

I will get more pictures tomorrow. Thanks for the suggestions already given.

 

[oldtexasdog]

I also put in a whole house surge protector but as was explained to me by the electrician a finger from God supersedes everything. Direct hits are just too fast and powerful.

 

[mkepke]

Man, that sucks.

Not much I can add, but I did notice that Laguna may sell just the control board for <$150

16-32, 19-38, 25-50 Drum Sander Intellisand Control Board - Laguna Tools Parts & Accessories

CONTROL INTELLISAND 110V (72-2250)

www.shop.lagunatools.com

I’ve heard the Intellisand is a pretty simple feedback circuit, but who provides electronics repair services these days?

-Mark

 

[ScottM]

It took a bit, but I did get the control box off. Here are more pictures of the open control box. I do not see anything burnt or exploded. Short of having someone who can check out the various components on the circuit board my next option is probably purchasing the control board that mkepke found.

I do have a question. The motor is a 90V DC motor. See last picture. I see the two leads going the motor (one black and one white). Is there any easy way I myself can test the motor. Where I live there are not electric motor shops.

 

[ssmith]

This is a tough one. Looking at the control board from Matt's link, there is only one thing on the board that could be a fuse (red circle) unless there's one on the other side .

You may be able to get your local electronics servicer to check the fuse, if that's what it is. Unfortunately, the problem could be that, a blown component on the board that's not obvious, or the motor.

No easy way to generate 90V for the motor comes to mind. TBH, though it's a bit of a gamble it may be easier to just replace the board and hope it's not the motor.

 

[ScottM]

No easy way to generate 90V for the motor comes to mind. TBH, though it's a bit of a gamble it may be easier to just replace the board and hope it's not the motor.

Since the motor is listed as currently unavailable, I am thinking the same way you are.

 

[JNCarr]

There look to be two surge devices on board - the one noted by @ssmith which may be a fuse and the blue object in the upper left (in the published picture) labelled "Z1". That's definitely a varister and as the name says it offers a variable resistance dictated by the applied voltage across it. It's normally very high resistance, but at a certain threshold its resistance drops to near zero and shorts out the lines. They are often used with an on-board fuse and the traces on the board would give the right wiring for that. The solder on the tan object looks to have been overheated. To test - UNPLUG THE UNIT. If you have an ohm-meter test across the tan part and you should get very close to zero ohms. Test across the blue part and you should get a very high reading. If either has been fried, the readings will be in reverse for which one (or both) is fried.

Those can be replaced for <$20 ($4 for parts, $16 shipping ), but as said above, there's no guarantee that other components have not been zapped also, so it's probably best to replace the board.

 

[Rick Mainhart]

The lumpy solder on what Scott identified as a fuse may well be pointing at one of the problems. Also, if the solder and/or fuse let loose, Z1 (looks like a Transient Voltage Suppressor or TVS) may well have fired.

I'm assuming you don't have a volt-ohm meter. At 40 RPM, you are NOT likely to turn the motor (gear reduction being what it is) ... if you can and do have said meter, you can put the meter onto the motor leads, turn the motor, and watch for a voltage (DC permanent magnet motors will act as a generator).

You CAN connect the motor to a 12 volt power source (car battery, etc) and see if the motor turns at all.

Scott, you're more than welcome to bring the board and motor by and I'll take a look at it for you ... Kernersville isn't THAT far away. Ping me if you're interested.

Good luck,

Rick

 

[kserdar]

There looks to be lots of poor solder joints in the picture ... Can you post a picture of the underside?

A cheap ($7 harbor freight) volt meter would tell you if the board is passing 90 Volts to the motor.

 

[ssmith]

Your comments about the solder blob and MOV prompted a look at the actual board. Looks like the varistor shunted a spike big enough to melt the solder and literally burn off the circuit foil on the board. The fuse couldn’t begin to stop it.

It might be possible to patch the board up, but it’s likely other parts on the board are damaged too. I’d suggest you just write the board off, pick up a new one, and hope the motor’s good.

 

[ScottM]

The board pictured above is off the Laguna website. Let me get a picture of my actual circuit board.

 

[ssmith]

The board pictured above is off the Laguna website. Let me get a picture of my actual circuit board.

Hey Scott - The picture I posted did come from Matt's link at Laguna but maybe I'm confused. Isn't this, the 2nd picture in your series, your actual board? Assuming it is, the circled area shows the apparent damage.