Old Reefer Containers and RCDs

[Eugenio]

Hi,
I design, and install switchgears for local farmers (berries production),
I live in El Bolson, Patagonia, sometimes I find reefers containers
(they are used here to store fruit and sometimes to get BQF and IQF fruit).
These reefers are old equipments, sold after to fullfill Its cycle on ships.
I do not repair these equipments, but some times I have to install switchgears
with protective devices, contactors, fault relays (phase and sequence, sub and over voltage)
and….. (here the trouble) RCD (Residual Current Devices) to protect against contact and earth fault currents.
I found reefers with earth fault currents.
Are RCDs used with reefers? What are the typical causes of these currents (if any)?
I am sorry if my electric lexical is not enough.
Thanks in advance.
Eugenio

[et0]

Are RCDs used with reefers? What are the typical causes of these currents (if any)?
I am sorry if my electric lexical is not enough.
Thanks in advance.
Eugenio

RCD is a good idea for any electrical equipment outside.

The cause is usually moisture in wiring or terminals, allowing current to flow to earth. If you are unlucky it could be the compressor motor. Check with a megger to find the leak (disconnect parts and check phase to ground).

An earth leakage, if left, will develop into a failure or a hazard eventually, so it's wise to fix it!

[Eugenio]

Thanks your reply.
“Yesterday” reefers were connected some years ago,
and I “inserted” the new switchgear with RCD,
so I had to bypass It to maintain 1 ton of fruit, but,
I explained customer (yesterday) similar ideas you point out in yours words.
(I smile when I read your words).
This post was to know if particular requirements should be apply to reefers
(i.e. no RCDs!!) since reefers I saw, comes originally without these protective devices.
Regards. Eugenio

[et0]

Ah, when I read your first post more clearly I see you are a sparky so you understand these things, of course :)

Sorry I don't know of anything specific to refrigerated units, hope someone else does - good luck!

[Eugenio]

Please, do not missunderstand me, your words were exactly I want to read. Thanks again.

[Brian_UK]

A common problem, as discussed here before...

http://www.refrigeration-engineer.com/forums/showthread.php?t=10389

[Eugenio]

thanks Brian your link,
I agree with some solutions
The use farmers gives to these equipments is opposite reefers where designed!
They open the doors often to put fruit from field.
I put reefers to earth through earth rod, to protect people from electric shocks.
But I bypassed RCD until resolve earth fault current.
I was re-reading a chapter from Schneider Electric, It may help another people too.
I do not know if the name is exact since some times I rename files.
Electrical_Installation_Guide_Schneider_F_ProtectionElectricalShocks.pdf
But with these data the file can be reached.
I do no attach the file. because It is 1.22 MB.
It analyzes several causes and solutions.
regards
Eugenio