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Electronics => Repair => Topic started by: Eltax1693 on September 24, 2019, 03:52:13 pm

Title: REOMED 1000 VA Isolation transformer
Post by: Eltax1693 on September 24, 2019, 03:52:13 pm

Hello

Bought a second hand unit from Ebay, seems to be made 2007.
REOMED 1000 VA 230v isolation transformer.

Sent an email to the manufacture, but they couldn't/want to help.
https://www.reo.co.uk/medical-transformer-reomed-i-1000 (https://www.reo.co.uk/medical-transformer-reomed-i-1000)

Two wires got loose in delivery.

1: Brown wire from the NTC´s [closest to front]

2: Black top wire from the inlet/switch

Does anybody have a clue to which terminals I need to reconnect?
Must be the relay to the left with markings T1 T2 T3 14 A2

https://datasheet.eaton.com/datasheet.php?model=051608&locale=en_GB (https://datasheet.eaton.com/datasheet.php?model=051608&locale=en_GB)

https://www.klocknermoeller.com/dilet/dilet11-m-a.htm (https://www.klocknermoeller.com/dilet/dilet11-m-a.htm)

Tnx

Title: Re: REOMED 1000 VA Isolation transformer
Post by: goaty on September 25, 2019, 07:16:47 am

I would be surprised if they did come loose just by vibration. Probably someone already tried a repair.
Look at the terminals of the Moeller and the Eaton to see which screw therminals never have been opened/tighned at all, so you can narrow it down.

Title: Re: REOMED 1000 VA Isolation transformer
Post by: Eltax1693 on September 25, 2019, 02:37:02 pm

OK, tnx for your suggestion. I check that.

Title: Re: REOMED 1000 VA Isolation transformer
Post by: andy3055 on September 25, 2019, 04:20:19 pm

That does not look to me as a transformer. Is it not a contactor? If you can zoom out and post a photo, it may be more helpful.

Title: Re: REOMED 1000 VA Isolation transformer
Post by: andy3055 on September 25, 2019, 04:37:12 pm

Or, are you referring to the potted part on the left?

Title: Re: REOMED 1000 VA Isolation transformer
Post by: TheMG on September 29, 2019, 11:28:53 pm

Do you intend to use this isolation transformer for electronics bench use?

If so, I will caution you that medical isolation transformers usually have the "neutral" side of the secondary earth-referenced. For use as an electronics/safety isolation transformer you will need to disconnect the neutral-earth connection on the secondary side so the secondary is floating. Otherwise, you risk blowing up a scope lead, or worse...

Title: Re: REOMED 1000 VA Isolation transformer
Post by: andy3055 on September 30, 2019, 03:21:32 am

Both of his links show a contactor made by Klockner Moeller-leading manufacturer of Electrical distribution equipment. I am not sure what the deal is for a contactor to be installed unless it is taking a very high current.

Title: Re: REOMED 1000 VA Isolation transformer
Post by: ArthurDent on September 30, 2019, 04:05:41 am

It apparently has a 'soft-start' feature to protect sensitive medical equipment plugged into it. You'd have to know more about the model number and options to figure out what's what. This might be the option you have.

"Option 30*:NTC + contactor Suitable for higher power so that the NTC resistance is by-passed with a contactor and can cool itself; this  option can  also  be  used  at  lower  power ensuring a  high  degree  of  safety especially  in  instances where the mains may be turned OFF and ON again in quick succession."

Check this out to see if it helps.  http://www.reo.co.uk/shop/files/reomed-i_ga-en_v01_17_ed3_1-operating_instructions.pdf (http://www.reo.co.uk/shop/files/reomed-i_ga-en_v01_17_ed3_1-operating_instructions.pdf)

Title: Re: REOMED 1000 VA Isolation transformer
Post by: Eltax1693 on September 30, 2019, 03:03:34 pm

Yes I´am aware of it. I figured it out. The two loose wires are connected to terminal T1. Works fine now. Tnx for the help/suggestions.

Did these modifikations: https://www.youtube.com/watch?v=Kkb6QCMjfic (https://www.youtube.com/watch?v=Kkb6QCMjfic)

Quote from: TheMG on September 29, 2019, 11:28:53 pm

Do you intend to use this isolation transformer for electronics bench use?

If so, I will caution you that medical isolation transformers usually have the "neutral" side of the secondary earth-referenced. For use as an electronics/safety isolation transformer you will need to disconnect the neutral-earth connection on the secondary side so the secondary is floating. Otherwise, you risk blowing up a scope lead, or worse...

Title: Re: REOMED 1000 VA Isolation transformer
Post by: andy3055 on September 30, 2019, 11:04:02 pm

Good the hear that.

Title: Re: REOMED 1000 VA Isolation transformer
Post by: Electro Detective on September 30, 2019, 11:31:06 pm

fwiw I'd still go through ALL the connections and triple check the lot to check integrity, especially after scoring a loosie wire or two already,

and test/verify just what type of input to output 'isolation' it actually sports, using a multimeter in AC and Low-Z modes to confirm,
after the usual powered off continuity checks

FYI: Certain measurements with Low-Z selected WILL trip your RCD, so watch out for that,
people in the dwelling may not be too impressed  :rant:  >:(