RCD for Heat Trace

What's your definition of an RCD?

RCD = residual current device = GFCI I think in america, detects current to earth and trips circuit accordingly

If the pipe is for something like water or air then I can't see the point. But if the pipe is carrying something that may degrade the insulations integrity then yes I would fit one.

Heat trace on air? Interesting...

To prevent condensation

Electrical heat tracing systems may be required to have Earth Leakage (Ground Fault or RCD) devices for personnel and equipment protection. The system design must minimize leakage current to prevent nuisance tripping.

First question: Where is the heat tracing installed?

This is an important question as where IEC rules are required the RCD is obligatory.

IEC 62395-1:2006 section 4.3 Electrical circuit protection requirements for branch circuits: The minimum requirements for trace heating systems are: c) ground fault equipment protection for each branch circuit. (page 11)

The same you will find in IEC 60079-30-1:2007-01 (which is the valid standard for EX classified zones) on page 23.

On top of this you will find that some manufacturers do require the use of an "RCD" on their cables. You just have to use them, even when you would have your own country were RCD's are not invented yet.

Why: the braid is there to be sure that each perforation with an object will result in tripping of the RCD.

Over the years the insulation of the tracing is continuously stressed, mechanically and thermally. In case it would fail it is important that the power is cut immediatly.

I know that there is still trace heating cable without braid on the market. They use a glitch in the standards, knowing that it will result in a product with a very competitive price or really nice margin. But other companies are really fighting these products as they know the danger behind.

This little line in the standards upon request of the manufacturers, who know from the past.

So what happens to the contents of the <...pipe...> between the time that the <...RCD...> trips, and someone investigates, tests for a fault, carries out a repair if needed, tests the integrity of the <...heat trace...> after repair if needed, and the time that that person resets it?