Foot control switch power box

[Stacy E. Apelt - Bladesmith]

In the Spinning Helicopter of Death thread I made a note of a foot control switch being a good way to safely turn things on and off. This is especially handy when both hands are needed to hold and control the object.

I drew up a schematic, and am building a prototype. The basic design will allow one of four tools to be controlled easily.
The operation is super simple:
Plug the control box into an outlet.
Plug the foot switch into the box.
Plug the tools into the box.
Turn on the power switch on the desired tool.
Step on the foot switch and the tool runs....step on it again and the tool stops.

The 125VAC control is managed by a 40 amp SSR. The control circuit is 12VDC and low current, so safety is no problem.
The switch is attached to the circuit by a phono jack. This allows the same switch to be jacked into your VFD and turn it on and off by foot,too. All you need to do to the VFD is put a NC jack in the remote start line. If the foot switch is there it runs off the foot switch. If it is not jacked in, the VFD runs as normal.

The schematic shown is the basic design. I will add some whistles and bells on the final build. Things like status lights for the foot switch ( On/OFF) and a fuse in the control voltage circuit.

More to come.

 

[johnnym]

Thanks Stacy, That looks like it will be very useful in the shop. There is a small wiring error in the schematic, both fan poles are connected to the 12 volt return.

 

[S R Floyd]

Man..... I would love to visit your shop one day! I think I would be in tech gadget heaven! I thought I was slick when I hooked up a sewing machine pedal to my sausage stuffer.

 

[Fellhoelter]

Very cool, this could be useful.

For lower amp stuff, HF sells a foot switch that works great.

Rated for 15a if I remember correctly, I have quite a few...

Item # 96618 for On/Off, or Item # 96619 for a momentary...

 

[stevomiller]

Nice job Stacy ;-).

 

[Frank Niro]

I had one for years on a buffing machine. It was commercially made . When it went down I chaged it to a regular switch and never really missed it. Frank

 

[Stacy E. Apelt - Bladesmith]

Johnnym,
Thanks, I was drafting too fast. I changed it.
I also took a look at what I had in project boxes, and an 8X8X4 box will fit the items just fine.

The HF foot switches and similar types mentioned are fine for some tasks, but when dealing with shop situations where hot or sharp objects could cut/melt into the power cord there can be a safety issue. By using the foot switch to control a low voltage circuit, there is no danger if something severs the cord. Those HF units could easily be converted for the task.