We bought a couple of tools at a school auction recently and all of
the 110 V tools there had a little yellow box called a Saf-Start on
the cords.
They seem to be a device to prevent re-start after a power failure or
a low voltage situation. Once you lose power you have to re-set the
button on the yellow box before the machine will run.
I checked the website http://www.jdsproducts.com/products.cfm
and it seems they have replacement pigtails or one model with a plug
so that you can add it to the existing power cord instead of having to
wire into the switch. There is also a 220v 3 wire model available.
At $90 it seems a little high but it may be cheaper than a new
magnetic switch.
I guess the school liked them because they had them on everything.

Mike O.

Mike O. said:

We bought a couple of tools at a school auction recently and all of
the 110 V tools there had a little yellow box called a Saf-Start on
the cords.
....
At $90 it seems a little high but it may be cheaper than a new
magnetic switch.

The same thing can be accomplished with a DPST 110v relay with
contacts sufficient to the load. About $8.00, plus the box, socket
and cords. Or a latching relay right out of the box.

You may also use more complicated devices such as TRIACs for quicker
switching times, but I don't think triggering on a several millisecond
'blip' in the power is something I want a tool to shut down for.

Or you can add fancy, lightning prone electronics to accomplish the
same thing - with a built in 'drop out' delay time.

I guess the school liked them because they had them on everything.

Law Suits and Government Waste - MMmmm, what a tasty combination.


Greg G.