UL508a Pressure Transducer

[doomed9]

A customer was looking to mount a UL listed pressure transducer inside of a UL508a control panel that also contains a meter and terminal blocks. I have not done this before and would like other's opinions on if this is allowed as I have seen conflicting information about whether or it can be in the same panel as electronic components.
If it is allowed, my current plan of action is to use a UL listed sealing washer where the customer would install the piping to the pressure transducer.
Is this a good idea or should I take a different route?
Thanks.

 

[Jraef]

Done all the time for compressor and pressure booster pump control panels. It's not a problem with UL, so long as the transducer is listed. We would typically run the tubing to fittings on the exterior walls so that no plumbers were having to get into our panels.

 

[doomed9]

We would typically run the tubing to fittings on the exterior walls so that no plumbers were having to get into our panels.

Don't the fittings need to be UL listed? I was looking to use the swagelok bulkhead connectors, but I thought I couldn't as it is not a recognized component.

 

[Jraef]

It's a "delicate" issue. Technically, if you have anything other than a Type 1 box, the fittings would have to have the same environmental rating as the box, i.e. Type 12, Type 4, etc. But by the same token, a plumbing pipe or tubing fitting is inherently watertight, so I never had a UL inspector challenge that.

If you get a persnickety UL inspector, you can use a UL listed cord grip bulkhead fitting (aka "CGB") or a "transit fitting" like Roxtec that will seal against the tubing. and just leave a stub of tubing on the outside for the installer to connect to in the field. I hated that option though, because no matter how well you protect it, those tubing stubs get bent or smashed before the plumber gets there.