Foot Switch for VFD?

AVigil said:
My disc has a KBMA-24D and I just plugged in the HF foot pedal and have been using it for months
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Ahh, that is the difference. That type is for 1HP and lower and has an internal relay. The switch stays in the ON or OFF position from what the circuit diagram shows. The OP has a KBAC-24D drive.


Ken,
Your last scenario would be the same as using the toggle switch. The whole purpose of the foot switch is having both hands on the blade when the belt starts moving. Turning it off can be done by hand with no issues. If a single foot switch was wired in parallel with the RUN contact (RUN to COM) the grinder could be started with the foot pedal, but would need the toggle flipped down to stop. That isn't a big deal, but start and stop function would be better.
A dual momentary contact pedal isn't all that big and would solve all issues. I ordered one to convert my TW-90 to full foot control. I'll post how it worked out.
 
Good catch Stacy - I didn't pick up on the KBMA drive being different than the KBAC drives. I've never even seen either drive, only looking at schematic manual for KBAC drives.

Stacy, if you look at the schematic in section 5.8 starting page 15 then on page 16 there is a remote NO "enable" switch shown. That switch "should" allow a single NO switch to be used, close switch to RUN, open switch to STOP - all with the single switch. from the manual: "The Enable function is established by wiring a switch or contact in series with the orange Main Speed Potentiometer lead which connects to Terminal “P2”. When the Enable Switch is closed, the motor will accelerate to the Main Speed Potentiometer setting. When the Enable Switch is opened, the motor will decelerate to stop."

With the enable switch you wouldn't have dynamic braking (if it's setup on drive) but should work just fine.

The switch I linked to before on https://www.amazon.com/dp/B07C17ZTL9 will NOT work as I described. The switch is a OFF-ON switch, press switch one time and contacts are closed, press switch again and contacts open. While that would work, it's not how I would wish it to work. I think best would be a NO switch to press down with foot to close (RUN), lift foot to open (STOP).

I just found this switch https://www.ebay.com/itm/392464657312? and think it's going to be exactly what is desired for foot switch. I placed the order and should be here next week. $8 shipped.
 
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That is good to know, Ken. Thanks.
The only issue is you have to keep your foot on the pedal. That may changing your stance and may cause you to be a bit "unbalanced" when grinding.
 
Stacy E. Apelt - Bladesmith said:
That may changing your stance and may cause you to be a bit "unbalanced" when grinding.
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I hadn't even considered that aspect - I was thinking I'd want my foot on pedal while grinding, but maybe not for all folks. My disk grinder usage is while sitting down so the feet are not moving around all that much. Perhaps the contact switch I linked to on Amazon might be better for some folks since it does "latch" in OPEN and also in CLOSED positions.
 
After posting that I realized all you would need was a latching ON/OFF foot pedal wired to the NO enable contacts. Step on the pedal to run, step on it again to stop.
 
An update on my comments about a footswitch for a diskgrinder. I did order the footswitch in the ebay link above and it's ok. It's a cheap plastic switch, but for $8 I wouldn't expect a good heavy duty metal enclosed switch. I wired up my VFD by putting the NO contact in series with the common line of the FORWARD-OFF-REVERSE circuit. This allows the grinder to be OFF when power is applied with the FORWARD-OFF-REVERSE in the OFF position. Placing the FORWARD-OFF-REVERSE in the FORWARD position the grinder is still OFF until I press down on footswitch. It continues to run until I remove foot from switch. I can then move FORWARD-OFF-REVERSE to the REVERSE position and control the RUN STOP function with footswitch.

Before I commented I wasn't sure if I felt this was a useful thing, didn't really feel it would be. I did a bit of grinding today on a blade with a grind line. Now I do feel this option is useful. I can place blade on disk, position exactly how I want it, then press with foot to run grinder. It seems to help. If I had the experience and skills of many of these folks perhaps it wouldn't be needed, but at my level of limited skill it does seem to help keep blade positioned properly.

Later
 
Update for this, picture attached
RWUUGk8.jpg


Sorry, i've been out on business all week, but i'm back tomorrow and finally get to try to mount my disk in the shop! Also got another tool that you'll see a thread up here about shortly. Still have questions about this guy though, so have we found what is the best solution for this (i need to be baby stepped, i'm serious electrically illiterate). Also, this has a main switch it seems? Should this always be on? Do i shut it off? It seems to store power if i turn it up, run the disk, stop the disk, put it in the down position, i can flip the motor on for half a second? Should i not be touching this switch? Can someone educate me?
 
I've not took time to dig thru the manual and figure how the KBAC drives are controlled. BUT, from looking at the photo it looks like it would as follows.

The switch in lower right corner seems to be the main power switch. Turn that switch to ON to power VFD. Is that correct?

The right most switch that says "START-STOP" (is that a maintained position switch?) seems to be the switch that would be used if the optional FORWARD-OFF-REVERSE switch wasn't installed. Since the FORWARD-OFF-REVERSE switch is installed the START-STOP seems to be no longer needed, so put it in the START position and forget about it. Use the FORWARD-OFF-REVERSE switch to STOP and select which direction to run.

Since I've never seen a KBAC drive much less used one the above is only supposition and VERY much open to correction. Does that seem to be how it works?

Your comment about "main switch", is that the main power switch in lower right corner? If so, YES, that switch should stay on the total time you're using the drive. Only turn it off at end of day. What you're seeing when it runs for a moment after turning that switch OFF is the capacitor bleeding down.

Ken H>
 
Ken H> said:
I've not took time to dig thru the manual and figure how the KBAC drives are controlled. BUT, from looking at the photo it looks like it would as follows.

The switch in lower right corner seems to be the main power switch. Turn that switch to ON to power VFD. Is that correct?

The right most switch that says "START-STOP" (is that a maintained position switch?) seems to be the switch that would be used if the optional FORWARD-OFF-REVERSE switch wasn't installed. Since the FORWARD-OFF-REVERSE switch is installed the START-STOP seems to be no longer needed, so put it in the START position and forget about it. Use the FORWARD-OFF-REVERSE switch to STOP and select which direction to run.

Since I've never seen a KBAC drive much less used one the above is only supposition and VERY much open to correction. Does that seem to be how it works?

Your comment about "main switch", is that the main power switch in lower right corner? If so, YES, that switch should stay on the total time you're using the drive. Only turn it off at end of day. What you're seeing when it runs for a moment after turning that switch OFF is the capacitor bleeding down.

Ken H>
Click to expand...


I think you're right on the money except the fact that the "START-STOP" isn't a maintained position. It returns to the middle after being pushed up - to start. Still trying to figure out what to buy to wire this, and where to try? Do i risk damaging anything if i don't get it right? Would reaching out toe KBAC be the best idea?
 
Ken H> said:
An update on my comments about a footswitch for a diskgrinder. I did order the footswitch in the ebay link above and it's ok. It's a cheap plastic switch, but for $8 I wouldn't expect a good heavy duty metal enclosed switch. I wired up my VFD by putting the NO contact in series with the common line of the FORWARD-OFF-REVERSE circuit. This allows the grinder to be OFF when power is applied with the FORWARD-OFF-REVERSE in the OFF position. Placing the FORWARD-OFF-REVERSE in the FORWARD position the grinder is still OFF until I press down on footswitch. It continues to run until I remove foot from switch. I can then move FORWARD-OFF-REVERSE to the REVERSE position and control the RUN STOP function with footswitch.

Before I commented I wasn't sure if I felt this was a useful thing, didn't really feel it would be. I did a bit of grinding today on a blade with a grind line. Now I do feel this option is useful. I can place blade on disk, position exactly how I want it, then press with foot to run grinder. It seems to help. If I had the experience and skills of many of these folks perhaps it wouldn't be needed, but at my level of limited skill it does seem to help keep blade positioned properly.

Later
Click to expand...

...told ya so. :)
 
Ken H> said:
I've not took time to dig thru the manual and figure how the KBAC drives are controlled. BUT, from looking at the photo it looks like it would as follows.

The switch in lower right corner seems to be the main power switch. Turn that switch to ON to power VFD. Is that correct?

The right most switch that says "START-STOP" (is that a maintained position switch?) seems to be the switch that would be used if the optional FORWARD-OFF-REVERSE switch wasn't installed. Since the FORWARD-OFF-REVERSE switch is installed the START-STOP seems to be no longer needed, so put it in the START position and forget about it. Use the FORWARD-OFF-REVERSE switch to STOP and select which direction to run.

Since I've never seen a KBAC drive much less used one the above is only supposition and VERY much open to correction. Does that seem to be how it works?

Your comment about "main switch", is that the main power switch in lower right corner? If so, YES, that switch should stay on the total time you're using the drive. Only turn it off at end of day. What you're seeing when it runs for a moment after turning that switch OFF is the capacitor bleeding down.

Ken H>
Click to expand...

Ken it sounds like you wired it like I need to, shooting you a dm.
 
DustinY said:
I think you're right on the money except the fact that the "START-STOP" isn't a maintained position. It returns to the middle after being pushed up - to start. Still trying to figure out what to buy to wire this, and where to try? Do i risk damaging anything if i don't get it right? Would reaching out toe KBAC be the best idea?
Click to expand...

By "trying to figure out what to buy to wire this, and where to try?" are you talking about a footswitch? If for a footswitch look at post #22 where I write: look at the schematic in section 5.8 starting page 15 then on page 16 there is a remote NO "enable" switch shown. That switch "should" allow a single NO switch to be used, close switch to RUN, open switch to STOP - all with the single switch. from the manual: "The Enable function is established by wiring a switch or contact in series with the orange Main Speed Potentiometer lead which connects to Terminal “P2”. When the Enable Switch is closed, the motor will accelerate to the Main Speed Potentiometer setting. When the Enable Switch is opened, the motor will decelerate to stop."

Reaching out to KBAC tech support is ALWAYS the best option, just ask him about this function referencing the above listed section.
 
DustinY said:
Ken it sounds like you wired it like I need to, shooting you a dm.
Click to expand...
Not sure you can send me a dm on this site since I'm not a member, but you can always send email to sailingtoo using the gmail service. Be happy to hear from you.
 
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