Eliminating zero speed start on a dc motor control

[RaisedByWolves]

It looks like there is another way to do this which is shown in the article
The wiper circuit is opened with another switch to stop the machine which would reset the return-to-zero circuit
Might be better than a cap

This sounds like what we are doing with the Custom Crafter controls.

I’m going to employ a mini Estop button which will act as on/off for the lathe/mill and also obviously an Estop.

Video outlining the hookup for the CC unit. Not a direct correlation for wiring, but proof of concept as the basics for the two are similar.

Found and purchased this tiny Estop button. Most compact one I could find even if it is a bit pricey, but it is high quality and waterproof.

https://www.ebay.com/itm/334082045010?var=543091439667&_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20221115143302%26meid%3De78860d75bcc4a719dc5d1001c61108b%26pid%3D101613%26rk%3D1%26rkt%3D1%26mehot%3Dnone%26itm%3D543091439667%26pmt%3D1%26noa%3D1%26pg%3D4375194%26algv%3DRecentlyViewedItemsV2Mobile%26brand%3DUnbranded&_trksid=p4375194.c101613.m146925&_trkparms=parentrq%3Aed24ab4f18b0ab8f6339eeb5fffc323c%7Cpageci%3A7bf70016-87b1-11ee-a352-9eab04fc32fd%7Ciid%3A1%7Cvlpname%3Avlp_homepage

 

[rrrickert]

Probably the cap would be connected between the O volt terminal of the pot and either the wiper or the top terminal:
I'm guessing it's likely the second way as that wouldn't affect the action of the speed control knob and make it sluggish to respond
View attachment 467269

Well the cap did not work. I did however figure it out. I disconnected one of the resistors. I will upload a photo tomorrow. Thanks for the help

 

[mattthemuppet2]

If it's an MC60 you're working with, disconnect the resistor going to (I think) the middle leg of the speed pot, pretty sure it's R13 from memory. Either way, it's the one next to RPS3 in the pic below

 

[markba633csi]

The 15K resistor? (brn, grn, org)
If that works then by all means- much simpler to do

 

[homebrewed]

I found an annotated schematic for the MC60 controller here. The 15K resistor you disconnected may be "R19" in the schematic. If so, it's part of the safe-start circuit. Considering what you want to do, I can see where you'd need to disable that feature.

BTW there are some things on that schematic that don't look right to me, so I would be careful when it comes to doing extensive mods if they are based on the schematic. I could get more specific on why I think it's got at least one serious error, but that really isn't needed for your purposes. Pulling that 15K resistor, you're OK in that regard.

 

[rrrickert]

This is a Minarik MM21030A. I have found that it is a better board then the MC60. But now the slow start is gone. I just had to disconnect one resistor. I had to play a little but it only took 2 tries to get the right one. Thanks everyone for your help.

 

[rrrickert]

I found an annotated schematic for the MC60 controller here. The 15K resistor you disconnected may be "R19" in the schematic. If so, it's part of the safe-start circuit. Considering what you want to do, I can see where you'd need to disable that feature.

BTW there are some things on that schematic that don't look right to me, so I would be careful when it comes to doing extensive mods if they are based on the schematic. I could get more specific on why I think it's got at least one serious error, but that really isn't needed for your purposes. Pulling that 15K resistor, you're OK in that regard.

My board is not an MC60. There is all kinds of info on those.

 

[homebrewed]

My board is not an MC60. There is all kinds of info on those.

That explains the different resistor numbers.....nevermind .