M5 Contactor

[bill]

For Vacuum control.....
"S,2,1/0" will turn on/off M5 w/START Router. Is there any way to defeat the "START" requirement and have full control via "S,2,1"?
OR.....
Where/What to buy for a 5VDC relay in order to use one of the other user outputs to then control M5.
Thanks,
Bill

[richards]

The reason you'll find self-latching contactors/relays in industrial equipment if to protect you. When a "Start Switch" has to be pushed before a device is activated (especially when two switches have to be pushed, one with each hand), the operator is protected from any unexpected movement of the machine.

If you really want to run a relay that doesn't require a start switch, just find a relay or contactor with a 5VDC coil that only requires 5mA to 10mA for activation. Wire one side of the coil to +5VDC and the other side to the output , if the output is active LOW. If the output is active HIGH, then wire one side of the coil to ground and the other side to the output signal.

[bill]

Thanks Mike. Point well taken w/safety as now retired from Industrial Controls. Just trying to use the current hardware in a different application.
The M5 contactor was purchaced from ShopBot just for this vacuum task and to keep all the hardware "like". Anyone have any part/mfg. suggestions for a solid state 5VDC relay to drive the 24VDC contactor?

[richards]

A solid-state relay may not work when it is used to drive the coil of a contactor or relay. A solid state relay needs to have a heavy enough load that it will positively turn off. If the load is too light, the SSR will stay turned on.

When I first started using SSRs, I had that exact problem. A call to Opto-22's tech support department helped me to understand how a SSR works and what the specifications on the data sheet mean.

[bill]

Mike, know what you mean. Been through the problems with lite loading along with the "undocumented" open collector and open emitter I/O devices. Annaway... ShopBot offers an interface board for 4 outputs designed to mate with their TTL outputs. Going that route. Thanks again.