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Spookydad
02-02-2013, 10:41 AM
I was finishing up a conversion of my Grizzly lathe from its' AC motor to a DC motor from a treadmill. I got careless and unplugged my mill instead of the lathe. When removing the control panel to wire in an E-stop, I touched two contacts of the speed control pot to the frame. Despite a 15 amp circuit breaker, it sparked and the motor controller got fried.

I don't have the skills required to track down the blown components so I am looking to replace the controller board. Should I replace it with another MC-60 or switch to another brand?

I have a 115v treadmill motor that is spec'd at 2 HP / 130 v, but I suspect that may be generous. Most of the cheaper controllers seem to max out at 90v and 1.5 HP.

I have a budget of $150 max.

Any thoughts would be appreciated.

Thanks

Neil

chucketn
02-02-2013, 11:46 AM
I have a MC-60 treadmill controller running a 2 hp motor on my X2 Mill and love it. Also have another spare that I use whenever I need variable speed. Next best controller in my opinion is KBIC-120. If you can't find another MC-60, I'd invest in the KBIC, around $70 US before shipping. Have you been watching your local Freecycle? That's where I got all 5 or 6 of my treadmills.. I've only used the MC-60 controllers, though I have a couple others.
link to some info on KBIC: http://www.galco.com/buy/KB-Electronics/KBIC-120

Chuck

firbikrhd1
02-02-2013, 11:52 AM
Hopefully MaxHeadRoom will chime in here. He has often given good knowledgeable advice regrading these issues to other members including me.
You can find good controllers on Ebay by KB electronics for reasonable prices. I have gotten 2 there for uses on 90V industrial DC motors and one for a treadmill motor I plan to use on my drill press. I suspect that the 90V/1.5HP controller would suit your purpose, but don't take my word for it. Max is the go to guy IMHO, but others here are probably just as able to give accurate advise.

Spookydad
02-02-2013, 12:50 PM
I have a MC-60 treadmill controller running a 2 hp motor on my X2 Mill and love it. Also have another spare that I use whenever I need variable speed. Next best controller in my opinion is KBIC-120. If you can't find another MC-60, I'd invest in the KBIC, around $70 US before shipping. Have you been watching your local Freecycle? That's where I got all 5 or 6 of my treadmills.. I've only used the MC-60 controllers, though I have a couple others.
link to some info on KBIC: http://www.galco.com/buy/KB-Electronics/KBIC-120

Chuck

How do you handle reversing the spindle?
Can you just wire in a switch on the two leads going to the motor?

MaxHeadRoom
02-02-2013, 02:11 PM
With the lower end 2 quadrant KB/Baldor drives, the reversing has to be done in conjunction with the I1 & I2, closing these cause the drive to got through a accel process to avoid shock in reversing the armature leads in mid rotation.
You can get the higher end 4 quadrant drives, these not only have dynamic braking but can be wired with a pot where centre is at zero spd, and either side is fwd/rev if required, so no reversing contactor/relay is needed.
Max.

chucketn
02-02-2013, 02:12 PM
Reversing a DC motor is accomplished by wiring in a Double Pole Double Throw switch between the motor and output of the controller.
Its a toggle switch available at most electronics shops like Radio Shack.
Here's an image of how it's wired.

http://www.google.com/imgres?imgurl=http://www.eleinmec.com/figures/012_02.gif&imgrefurl=http://www.eleinmec.com/article.asp?12&h=275&w=285&sz=5&tbnid=IQOa6WakjHlQNM:&tbnh=88&tbnw=91&zoom=1&usg=__fTaHDhplK2OpW1v7n4rRuwtMXVg=&docid=pOoqJYmpJh8geM&hl=en&sa=X&ei=1WQNUai6G4_a8wS3t4HIDg&ved=0CDsQ9QEwAg&dur=4464

Chuck
edit to correct switch name and description

MaxHeadRoom
02-02-2013, 02:17 PM
Reversing a DC motor is accomplished by wiring in a Double Pole Double Throw switch between the motor and output of the controller.
Its a toggle switch available at most electronics shops like Radio Shack.
Here's an image of how it's wired.


See post #5 on I1-I2 and KB manual for more info on reversing.
If you buy one of these units that is in an enlosure with reversing switch, there is a special switch that does not allow going from fwd to rev in one action and also has two terminals for the Inihibit pins
Max.

Mike Amick
02-02-2013, 03:02 PM
I use Dart's and KB's and really don't think you can go wrong .. as long as you get one that
handles the volts and current.

You could try and grab a couple more treadmills .. and hope to get lucky .. but most treadmills use
use those damn controllers that have the time delay when starting.

I think that link by Chucketn was pretty good and well within your budget.

Mike

chucketn
02-02-2013, 05:07 PM
The MC-60's I have don't have a time delay, but do require turning the speed control to zero, like the safe start feature of the SEIG lathes and mills. To be honest, I haven't used a MC-60 controller with a reverse switch like I described. Haven't had an application for them that needed reversing.
I did build a home brew X axis power feed from a DC gear motor, PWM Controller from China, and a laptop power supply that did include a reversing switch as I described earlier.
Chuck

caveBob
02-02-2013, 08:24 PM
See post #5 on I1-I2 and KB manual for more info on reversing.
If you buy one of these units that is in an enlosure with reversing switch, there is a special switch that does not allow going from fwd to rev in one action and also has two terminals for the Inihibit pins
Max.

That's what I did after your advice... went with the KBMD-240D as it already was mounted in the enclosure, was easy to add fwd/reverse switch and heat sink.



over at ebay...:

New KB Electronics DC Motor Control, KBMD-240D
$114.99 + $11.69 Economy Shipping
Item number: 290804385109

The optional forward-brake-reverse switch is part number 9860, $54.99, listing 290758111920.
The optional heatsink is part number 9861, $31.23, listing 300734056087.

Cost a little more, but when I upgraded my treadmill motor to a Baldor CDP3440 that I found dirt cheap on ebay, just had to pop a new $2 - 3/4 hp resistor and was good to go:

http://oi46.tinypic.com/rseqo6.jpg

http://oi45.tinypic.com/jq293t.jpg

new motor:

http://www.myimg.us/images/12.01.12/30543.jpg

with belt tension jack:

http://www.myimg.us/images/12.01.12/30542.jpg

Saw a nice article where he used the same motor on his Grizzly here (where I first heard of this great little motor):

9x20 Lathe Variable Speed DC Spindle Motor
http://www.micro-machine-shop.com/Variable_Speed_DC_Spindle_Motor.htm

also look at the "KBIC-125" when you're at ebay it's ~$75 new.

caveBob
02-02-2013, 08:43 PM
As much as I like the vari-speed for the spindle... I like it also for the leadscrew, Evan here helped me with the wiring config. Pardon the gloat, but it is well worth considering doing if you haven't already:

http://oi47.tinypic.com/i27v2p.jpg

http://oi47.tinypic.com/5xmo8g.jpg

no springs just gravity... loose:

http://oi49.tinypic.com/kcywaq.jpg

slide the motor back to tension the belt:

http://oi47.tinypic.com/2irkso1.jpg

I was just cutting some stress-proof steel this week and it's a little... I don't know what... not gummy, but kept getting a mouse tongue surface finish untill I ramped up the spindle speed pretty high with a verrry slow feed rate on the leadscrew... awesome finish. I like variable speed...