E-STOP Circuit - will this cause any problems?

[audioandy]

As I said previously, K1 is the contactor. Terminals (1) and (2) are N.O. contacts that will switch the L and N when the contactor is latched following a reset. The latching circuit will obviously drop out if an E-Stop is active. BTW, there aren't any N.C. contacts on the drawing I posted...

No but you mention them in your post, my fault for assuming!

[Shinobiwan]

Andy, there's nothing wrong with wiring the mains through the estop. Pro's like Strike CNC have been doing it for years! Lol

[audioandy]

Andy, there's nothing wrong with wiring the mains through the estop. Pro's like Strike CNC have been doing it for years! Lol

It makes me cringe to think how many of their machines are out there still being used and a potential death trap!

[birchy]

K1 is the 24V DC contactor. All the safety stuff will be run from the 24V DC supply, so the E-Stops will be 24V and NOT 240V. I've not yet drawn the latching circuit. The above drawing is only for the AC side of things and doesn't show any E-Stops. I do have a Pilz safety relay but am limited on space due to its height, so will use a contactor instead.

[audioandy]

K1 is the 24V DC contactor. All the safety stuff will be run from the 24V DC supply, so the E-Stops will be 24V and NOT 240V. I've not yet drawn the latching circuit. The above drawing is only for the AC side of things and doesn't show any E-Stops.

Ok I will let you off this time

[Web Goblin]

240VAC can be used for estops but its not very common on machine controls these days. Most pro companies machinery that I have worked on always use 24VDC for control circuits.

[Web Goblin]

Birchy thats the safest way to do it especially if you are going to have a hand held control box at any time.

Damn Andy beat me. Need to type faster.

[birchy]

FWIW, I work in engineering and have built many machine control panels over the years, so am familiar with standard conventions. However, CNC conversions are new territory and I'm a little concerned that I might blow a drive card or something if I break the wrong circuits on an E-Stop.

[Web Goblin]

Birchy I take it that your control pcb does not have estop contacts?

[birchy]

Birchy I take it that your control pcb does not have estop contacts?

It's a PCPPS V3.0 board. Doesn't appear to have any E-Stop contacts on it. My thinking is that if I kill all the AC devices, then the 50V supply to the steppers will also be killed which should be as safe as it can get?