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Posted By Topic: heat pump

12345
Sep 24 2016 07:28

i know that the heat pump or air conditioning unit must be in a separate circuit protected by MCB. But what about the RCD. We really need to protect the circuit by RCD as well. i like to get a clarity in this matter. so, anyone please!!!
Cheers.
   

AlecK
Sep 24 2016 08:42

"i know that the heat pump or air conditioning unit must be in a separate circuit..."


Why? Might be a good idea, but there is no such rule.


" ...protected by MCB."

Again not necessarily true.


" But what about the RCD. We really need to protect the circuit by RCD as well"

Why? RCDs are "additional protection", meaning "additional fault protection".
We use additional protection where there is increased risk of a person being subjected to dangerous touch voltages from a fault.

There's nothing inherently dangerous about a heat pump circuit. People don't climb up to change lamps without isolating. People don't plug things into it.
   

Sarmajor
Sep 24 2016 12:17

The heat pump can be connected to any circuit that you want to connect it to as long as the circuit can
1. Supply the required current.
2. Meet the voltage drop requirement.
3. Meet or better the EFLI requirement (if not RCD protected.
4. Not have an adverse affect on the installation.

We don't protect appliances with MCB's or RCD's, we protect the installation cabling..

In some cases a standard RCD may actually cause nuisance tripping if the heat pump is poorly designed inverter typ