Overland Conveyor E-stop oull cords wired through PLCs

[majesus]

We have a 3km overland conveyor project that requires emergency pull-cord stops. The customer wants to know which safety switches is pulled via a PLC/HMI.

Anyone have experience with this type of application?

Thanks

 

[roydm]

Some of the posters suggest a Safety PLC, I don't see that.
No-one is going to be working on the conveyor with just the pullcord pulled. It must be locked out!
The problem with long conveyors is finding the switch that has beem pulled. I don't think running each switch back to a common point is an option. My suggestion uses 1 4c cable to pick up all the switches in series.
Roy

 

[majesus]

The solution used was a Pull Stop with two NC contacts.
One switch was wired in series along the conveyor using a DC source then hard wired directly to the conveyor's power source using an interposing relay.

The second switch were grouped per 200ft, and then wired into a remote I/O port, they were then radio back to the main PLC for "pulled switch" detection.

Maj

 

[itsmoked]

Thanks for the update!

Keith Cress
kcress -

http://www.flaminsystems.com

 

[roydm]

Sounds like a good solution
Thanks for the feedback
Roy

 

[majesus]

Thank you guys as well.

Love it.

 

[tbmcontrolsengineer]

The Austdac stuff is wicked expensive. plus their system is a 3 wire system. Ringline is a copy of dupline. I use the new Dupline safe system. all of the safety components are SIL3 cat4. It is possible to do a 3km run using #12 AWG depending on your switch spacing.

regards.
CE