intrinsically safe barrier safety rated

[jdbrandt]

OK I just got dropped in another somewhat odd job. I have to do have safety door switches E-stops in a classified area Class 1 DIV 1. The mechanics of installing them is not the issue my concern is the intrinsic barrier that I have found are not rated for safety devices. Anybody have a clue about this.

The last couple of jobs the customer has signed off on the barriers being non safety rated as-long as we did 4 wire 1 wire on an individual barrier. So we used 4 barriers per E-Stop and Gate Switch. I usually use 2 channel barriers but for these I only used 1 channel.



Any Ideas?

Thanks for your time

IMHO, you need to stop thinking electrically.
Why not use keyed-interlock devices, with the signalling portion in a non-classified area?
There are a variety of suppliers out there, but the concept is that a captive key stays on the control panel, and, when removed, initiates a stop. Then, the same key opens a MECHANICAL lock in the classified area.
Used them all the time 'back in the day' of solvent-based printing.

 

[JeffKiper]

We have people walking on the conveyor every 6~9 minutes at 3 different locations. On this one they will all enter at the same time but other systems they enter at different times.

 

[BTalbot]

Here is one style of "trapped key"
http://www.fortressinterlocks.com/index.php/16/what_is_mgard.html

 

[iant]

sorry but a traped Key is not an E/Stop

 

[James Mcquade]

Have you looked into Pilz?
they have zero volt contacts for their e-etop relay.
its been 8 years since i worked on one.

regards,
james