ECN Forum Forums General Topics of the Trade General Discussion Area Heated ice/snow melting mat

Would a ice/snow melting mat require ground fault protection for equipment according to the NEC? According to the pdf below, it actually indicates no ground fault protection should be provided. I just wanted to make sure the instructions are not in conflict with the NEC.
http://www.barcoproducts.com/uploads/store_item_tabs/963B50AEF628490FA6BCCFF8CE85ACBE.pdf

Frank,
Should be okay if the installation is in accordance with NEC 2008 210.8[A] and 210.8[B] exceptions.

At least they have built-in ELCI, right?

They may be referring simply to capacitive losses- a mat of this design is, by nature, going to shunt some current straight to ground by simple capacitance and may nuisance-trip the GFCI.

Every 15A or 20A outlet pretty much anywhere a consumer would be putting a cord-connected mat like this would have GFCI protection as absolutely required by NEC. The only exception would be an inaccessible dedicated outlet specifically for this mat, which is where the sparky comes in. Of course, they don't qualify this, and is joe homeowner REALLY going to pay to have a new dedicated outlet installed, or just defeat the GFCI he's got his extension cord plugged into when it starts tripping?

I forgot to mention that the rating of the electric mat is 240 volts, 10 amps and is for a non-dwelling application.

This is my read.

From the link:
Some of the mats are 240 volts due to their large size. The exterior GFCI requirement from 210.8(A) and (B) only applies to 125 volt, 15 and 20 amp circuits. Although it is not required for larger circuits, the property owner needs to decide the level of liability they are willing to take with the mat, especially if the mat is going to be in a public area. I presume these mats are tough but not bullet proof. With shoe cleats, high heals, and just general traffic will eventually damage it. Although it has ELCI protection, it is not the same as GFCI protection. ELCI has a higher tripping point. If a 240 volt mat were to be used, I would consider using a GFCI breaker especially if there is anything conductive within hands reach where the mat was going to be installed and the level of relaibility in that the mat will be properly inspected.

426.28 requires ground fault protection for the mat, however the built in ELCI provides this protection.
Don

Thanks Don. That was the article I was looking for.