Enclosure for Inverter

[derek hall 1Participant @derekhall1]

Hi

Just wondering what would be a suitable enclosure for an inverter?

I have a small 3 ph parvalux 190w motor that I wired up to a suitable inverter. All working fine. I plan to use external stop, start and forward/reverse buttons on the outside of a suitable enclosure instead of the small controls directly on the inverter itself.

However I have seen pics on here and elsewhere of inverters just hanging on a wall near the machine, complete with exposed terminals ….this seems very unsafe!

So I was thinking about putting the inverter in an enclosure but should it be plastic or steel?, and what about suitable ventilation as inverters tend to get warm? Would a steel enclosure act as a heat sink for example?

Looking forward to suggestions

Kind regards

Derek

[derek hall 1Participant @derekhall1]

[Ian ParkinParticipant @ianparkin39383]

Either metal or plastic will be fine

just a fan to let out the heat and an inlet filter to let cool air in

[David JuppParticipant @davidjupp51506]

Perhaps start by reviewing the documentation for the chosen inverter – that will often include guidance on how much space to leave around the inverter when mounting.

A metallic enclosure will to some extent act as a heat sink – but depending on size of enclosure it may still be necessary to arrange ventilation of the enclosure. Typically 2 grilles, and perhaps a fan. Some inverters include a fan on the integral heatsink that might help stir the air around any enclosure.

A metallic enclosure is generally preferred for EMC reasons as well as thermal management.

Some (not many) inverters are designed for installation without a protective enclosure, but most are designed to be mounted inside a suitable control panel or other enclosure.

Ventilation grilles, dust filters, fan modules etc are typically available as accessories for electrical enclosures.

[John HaineParticipant @johnhaine32865]

I haven't used any inverter that doesn't have covers on the terminals – though they may be exposable for wiring up.

[Benjmain PoweskiParticipant @benjmainpoweski98989]

Many inverter manufacturers like Invertek offer models with different nema rated housings but it certainly looks nicer to have it all in an enclosure.

I suggest strongly measuring it all out first as I always think a smaller enclosure works and playing Tetris once mounted is a pain. Be mindful of spacing requirements. I setup air vents in mine but it probably wasn’t necessary.

Restoration

[Robert Atkinson 2Participant @robertatkinson2]

Derek,

Someting from this range or similar is ideal

https://uk.rs-online.com/web/c/enclosures-server-racks/enclosures/wall-boxes/

Sometimes you can pick up a used one (with bonus par inside sometimes) on ebay wth creative search.

Follow the inverter manual for minium space required around the inverter. Don't forget strain releif glands for the cables.
Yo cn of course DIY box. If you use wood or similar I'd increase th sisze a bit and put ventholes (with protection against swarf ingress) in it.

John,

None of the typical inverter drives are suitable for mounting without an enclosure in an accessible or exposed location. They do not have proper environmental protection, touch protection for terminals or strain reilef for the cables.
Just because "everyone does it" and they mostly get away with it is no reason not to do it right.

Robert G8RPI.

[derek hall 1Participant @derekhall1]

Thanks for all the replies…..Robert, I never thought of a wooden enclosure…!

Regards to all

Derek

[old martParticipant @oldmart]

I bought a locking electrical box on ebay for the Tom Senior at the museum and added top and bottom shielded ventilation. It is mounted on an arm which can be moved up and down and swung back and forth.

 

 

 

Edited By old mart on 14/11/2021 18:09:32

Edited By old mart on 14/11/2021 18:10:57

[EmgeeParticipant @emgee]

Derek

FLC on such a small 3 phase motor will be next to nothing, I can't imagine a VFD becoming overheated with such work.
Some/most models have an IP20 rating which I would happily use in my dry and heated workshop without any further enclosure provided there was provision for glands for cable connections and the unit was fitted away from any flying metal particles.

If you really feel the need to mount in an enclosure I would advise metal with good area around the VFD, unless you intend to run the VFD at it's maximum rating for long periods I don't think forced ventilation will be needed but you sound like a belt and braces person so perhaps you will also fit a fan and inlet and outlet grills/louvres.

Emgee

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