Safety switch test

[Warren Lake]

if power went out and a machine was running it would not start when the power came back on. The switches take care of that when the coil disengages when the power went off. Anyone running a roto then its even more so as there are other things supplying the power that are not going to start.

I wont be putting a mag starter on my belt sander though, more weight if I enter the sander into belt sander races.

Can a mag starter fail and stay engaged. Yeah it can but its rare. Ive had one in over 30 machines do that when my compressor would not shut off cause the coil had arced in the engaged position. It was 37 years old and its mounted on the compressor so its had its ass rattled off for many years.

[Bill Dufour]

If I am ripping a long heavy board and it starts to bind then the lights and power go off I do not want to have to fumble around to stop the saw while staying out of the path of any kickback in case it restarts.
I was surprised to find my jointer push button switch was just off/on and no way to tell which before I plugged it in after changing the knives. I must have touched the switch because it was on as soon as I plugged it in.
Bill D

[Warren Lake]

ripped tons of 10 foot solid, if a board started to close and some amount did I just lifted them off.

[Edward Weber]

I
Now, I'm not saying I wouldn't buy a tool with a mag switch. It's fine if it has one. I just wouldn't treat it any differently if it had a mag switch or not. If the power goes out, I'm immediately turning the machine off so I know it's off. So the mag switch doesn't offer me anything because I'm not willing to risk my health and well being on a convenience.

If the power goes off, a machine with a mag switch is physically disconnected from the power source. There is no "turning it off" it's already off.
It's off as soon as the power is gone. You can press the switch all day long, it won't do anything once the power is cut.
I also didn't imply that they were a substitute for good safety practices, I just said they're not doo-dads or gizmos. They're probably one of, if not the best, safety systems out there. A bit more than a convenience.

You can choose to use them as you like but not everyone on the forum knows what they are or how they work. Simply dismissing them out of hand doesn't inform or help those members.

[Warren Lake]

Switches are a part of machines.

Gizmos are all those plastic and other things with wheels and. No use for most of them but a mag switch yes for sure. A number of machines came with no starter and ive had to source and instal and on some machines, now over time replaced some of them. One brand not around anymore had a number of failures in time.

I had the best luck with Danfoss and likely one of them is 60 years old or very close. They got cheaper than the originals over time metal cases became plastic then made in Poland and those were still fine. Danfoss stopped making those switches and ive been able to find some old stock.

[Rollie Meyers]

A safety switch is a enclosed switch, either fusible, or non fusible, general duty, (240V max), and heavy duty, (240V & 600V), available in NEMA type 1, or 3R, for general duty, & heavy duty, plus NEMA type 4, watertight, 4X watertight corrosion resistant usually stainless steel, NEMA 12 dust & oil tight, which the NEMA type 12 is what I prefer for wood & metalworking machines. What is described as a "safety switch" by the OP is simply 3-wire control with two push buttons with one with NO, normally open contacts, and a NC, normally closed contact, wired with a magnetic starter, or if overload protection is not desired a magnetic contactor.

[Ken Flesher]

"safety switch' is a generic term.
For those little yellow "keys" and lockouts, they're just nonsense. They do nothing other than to let you know they're there. I know of no ono who has ever actually used one of those little plastic keys as they're intended. They break easily, get lost easily, they are just the manufacturers way of covering their backside.

Well now you do.

Much of my career at a University was overseeing a shop space used by students in various coursework. Woodworking, welding, metal fab, etc. If a tool had one of those keyed switches, you better believe the yellow key was pulled out and locked away when classes were not using them. I never had one break, and I never lost one.

[Edward Weber]

Well now you do.

Much of my career at a University was overseeing a shop space used by students in various coursework. Woodworking, welding, metal fab, etc. If a tool had one of those keyed switches, you better believe the yellow key was pulled out and locked away when classes were not using them. I never had one break, and I never lost one.

I never lost one either because I leave them in place and don't have children or students or anyone who would/could possible lose one on me.

I do think I may have Jinxed myself, after my post I had to buy one of those (4 pack actually) for a saw I'm rehabbing. Karma set me straight.