VRF Ground Leak Detector

[xguard]

Looking through the manual for a VRF we may use I see the following note:

"Be sure to install a ground leak detector. (This unit uses an inverter, which means that a ground leak detector capable of handling high harmonics must be used in order to prevent malfunctioning of the ground leak detector.)"

I've used ground fault detection on ungrounded systems and ground fault relays on control systems using phase to phase control voltage. I haven't used a ground leak detector and haven't came across anything with that specific name. This will be in a typical office building with a grounded electrical system. Anyone familiar with this? What type of 'detector' is used, where it's installed, relevant code requirements? Thank you.

 

[Jraef]

Given that they are likely a foreign manufacturer, I would interpret that to be their way of generically referring to what we in North America would call “Equipment Ground Fault” protection, or GFEP (but not GFCI which is far more sensitive). In some parts of the world this is called “RCD” (Residual Current Detection), elsewhere it might be called an “ELCB” (Earth Leakage Circuit Breaker), etc. The point being rather than trying to include all of the different names, they tried to come up with a more generic term.

Which of course backfired on them...

Our code would not dictate the need for GFEP unless it was over 1000A, except under the more generic issue of “install per the manufacturer instructions”, which in this case seems to say that. Then, they are putting in a CYA statement about it needing to be insensitive to harmonics in order to avoid any responsibility for it causing nuisance tripping, which is unfortunately common on equipment with inverters. Since they don’t specify a level, I would go with a 100mA trip level to avoid that.

 

[priyankasethi]

ASHRAE 15 requires the checking of refrigerant breaks under specific conditions inside a mechanical room, however shouldn't something be said about a consumed space where refrigerant is coursed through VRF/VRV (Variable Refrigerant Flow) Indoor Fan Coils? When is a VRF Refrigerant Leak Detection framework needed in a consumed space? The chance of a break is consistently present and its relocation into the consumed space makes certain to occur if this happens. In certain pieces of Europe a refrigerant screen is needed for consumed spaces that have the ability of being weakened with a refrigerant break. In spite of the fact that in the United States generally this necessity is met by applying the ASHRAE 15 and 34 count for the adequate least room size dependent on the volume of refrigerant in the framework. The refrigerant screen framework is sufficiently little to fit into an electrical outlet box, which makes for a snappy establishment and accommodates a stylishly satisfying appearance as it is flush mounted. The refrigerant break indicator ought to be mounted between 12" to 18" of the floor, as refrigerant is heavier than air and will collect along the floor. The refrigerant observing framework can likewise be situated in upper room spaces where line manifolds, fittings or gear associations may spill. Abstain from putting refrigerant hole location gadgets in zones that need air development, for example, in corners or behind entryways.