Saf-Start

[Mike O.]

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

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.

[Greg G]

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.

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

Greg G.