Sealing Terminations and Cables

[elmarea]

I'm a controls technician for a Natural Gas Utility. We're wiring devices in a C1D1 location.

The company lost its experienced technician who used to do all the hazardous location wiring. I've been asked to wire this device and use his previous installations as an example. I have no engineering support on this job.

The trouble arises when I get to the terminations. The devices are temp and pressure xdcrs rated for the location. (C1D1 XP) Rigid steel conduit with 2 conductor shielded cable.

I'm saying sealing at the device is required per Art 501.5 (D), (working from memory code bk at work) plus Mike Holt's guide on special occupancies, but the previous technician neither sealed the cable at the device end nor the terminations at the cable ends.

Is sealing of the cable and terminations at the device end required? What products do you use to seal if required?

Thanks

 

[pierre]

Re: Sealing Terminations and Cables

I admire your courage in trying to tackle this job, but you are in over your head. Hazardous location work is not something to guess at. Experience plays a major role in the successful installation and trying to duplicate someone's installation is not the correct way to go about it.

You need to convince your employer that this is too much for you and they need to hire an expert in this field.

Good Luck

 

[rbalex]

Re: Sealing Terminations and Cables

I?m assuming from the Sections you are citing you are referencing an NEC edition earlier than the 2005.

This is sort of an interesting application because, while the conduits in all likelihood don?t need to be sealed, the cables do.

Because the cables are shielded they aren?t required to be sealed by stripping back the insulation. See 501-5(D)(1) Ex. The conductors within a common jacket are permitted to be treated as a single conductor if the jacket is vaportight. Note UL product standards certify most multi-conductor cable jackets as vaportight.

In summary, I agree a seal at the terminations is an NEC requirement as you have described the application.