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Old 8th Jul 2022, 12:21 am   #1
Michael Maurice
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Default Antique Belarusian Samovar

I have been asked to repair a Samovar.

There is a problem with the ceramic parts that hold the element in place.

What concerns me is that there is no earth on the thing, and no provision to connect an earth on it.

Do I try and repair it or just return it on the basis that I can't be sure how safe it would be either now or in the future?

I'll supply pictures next week if you want.
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Old 8th Jul 2022, 7:57 am   #2
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Default Re: Antique Belarusian Samovar

I think we both know what the "official" answer is.

If I were doing it for myself, I'd either modify it so that it can be earthed, or consider permanently wiring an isolating transformer to it (I have no idea what power these consume though).
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Old 8th Jul 2022, 9:07 am   #3
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Default Re: Antique Belarusian Samovar

Personally I would just return as not able to be repaired safely, modifying it is another can worms as was discussed on another thread.

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Old 8th Jul 2022, 9:52 am   #4
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Default Re: Antique Belarusian Samovar

Thank you both for your advice.
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Old 8th Jul 2022, 10:01 am   #5
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Default Re: Antique Belarusian Samovar

From looking at other threads about these here, power consumption seems fairly low, and they seem intended to be run for extended periods. So maybe an isolation transformer might be realistic.
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Old 8th Jul 2022, 10:05 am   #6
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Default Re: Antique Belarusian Samovar

It should certainly only be used with an RCD as it is, either plug-in or at the consumer unit.
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Old 8th Jul 2022, 10:11 am   #7
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Default Re: Antique Belarusian Samovar

A candidate for a permanently attached RCD plug maybe.
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Old 8th Jul 2022, 12:11 pm   #8
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Default Re: Antique Belarusian Samovar

Don't forget that as far as UK regulations are concerned, an RCD must not be used as the primary means of preventing electric shock.
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Old 8th Jul 2022, 1:26 pm   #9
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Default Re: Antique Belarusian Samovar

It's exempt as a "historical item", exactly the way that historical vehicles that can never meet modern safety standards are exempt from testing and can still be insured and used legally on the roads. We're all aware that vehicles can't be discussed on here, but in the outside world that's always the comparison that I make when asked this question. Thank goodness that the auction houses are now finally realising this and are now generally stopping the ridiculous practice of cutting off or completely removing mains leads from vintage electrical goods. The item in question is still lacking in the modern electrical safety department and the best thig to do is to tell the customer that it can be repaired, but warn them that it doesn't comply to modern standards and can't be legally made to do so. There's one complete answer to the problem and that is to run it from an isolation transformer of the correct power rating, which would be the equivalent to putting your historic, classic vehicle on a suitable trailer and towing it with your 'modern'. We know we can't start talking about vehicles, but this comparison exactly covers the question perfectly.
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Old 8th Jul 2022, 1:32 pm   #10
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Default Re: Antique Belarusian Samovar

Quote:
Originally Posted by Techman View Post
It's exempt as a "historical item... There's one complete answer to the problem and that is to run it from an isolation transformer of the correct power rating, which would be the equivalent to putting your historic, classic vehicle on a suitable trailer and towing it with your 'modern'.
I think that comparison's a bit harsh; after all, the tx. could be hidden away out of sight and the item would function as intended, but I agree with your overall point.

But are the legal people out there as down-to-earth and sensible as you?
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Old 8th Jul 2022, 2:00 pm   #11
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Default Re: Antique Belarusian Samovar

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Originally Posted by Nickthedentist View Post
after all, the tx. could be hidden away out of sight and the item would function as intended
I think it was said that the item doesn't use as much power as one would think, but all the same it has a heater, so I'm thinking that any suitably rated transformer couldn't easily be hidden away. Another thing is that strictly legally speaking, any isolating transformer would have to be a purpose made and bought item and not something popped into a wooden box or grafted to the inside of the unit in question (if it's for a general member of the public), therefore I stand by my trailer comparison.
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Old 8th Jul 2022, 2:06 pm   #12
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Default Re: Antique Belarusian Samovar

Agree with the above. In the workplace one takes all reasonable measures in order to comply with PUWER and EAWR. That can mean applying newer standards than were in force when something was made, leading to automatic upgrading and obsoleting of older equipment. But these don't apply in the domestic environment, where product regulations are not retrospective. And while you are carrying out the repair in a workplace you can be taking special measures to ensure safety.

I would repair as-is, if the repair can be made at least as sound as the original configuration and that this can easily be shown to be true. If there is any doubt about the mechanical integrity of the insulation due to the damage and subsequent repair, I would not repair.
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Old 8th Jul 2022, 3:46 pm   #13
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Default Re: Antique Belarusian Samovar

Quote:
Originally Posted by Michael Maurice View Post

Do I return it on the basis that I can't be sure how safe it would be either now or in the future?
If it was me, that's what what I'd do, Michael.
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Old 8th Jul 2022, 4:35 pm   #14
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Default Re: Antique Belarusian Samovar

Replacing the mains lead would be regarded as a responsible repair approach. Using a 3-core replacement lead with the earth wire connected to the Samovar metalwork would equally be a responsible approach, assuming that the metalwork is continuous.

The ceramic element supports do sound like a potential risk area because it may be difficult to effect a replacement without serious design modification which introduces its own safety responsibility problems as we discussed here in connection with the dangerous amplifier toggle switch.

I agree with the suggestion to use an RCD, but wouldn't be at all surprised if it were to give problems with tripping.

Martin
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Old 8th Jul 2022, 5:25 pm   #15
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Default Re: Antique Belarusian Samovar

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Replacing the mains lead would be regarded as a responsible repair approach. Using a 3-core replacement lead with the earth wire connected to the Samovar metalwork would equally be a responsible approach, assuming that the metalwork is continuous.
You can't legally do that!

It will change its class of operation, putting it into a new class the specifications of which it can never meet or comply with. I used to keep saying this regarding non-qualified people fitting earths to record players and radios where no earth was originally fitted. I've pretty much given up trying to tell folks and just let them get on with it now - they have to do what they have to do!
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Old 8th Jul 2022, 5:42 pm   #16
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Default Re: Antique Belarusian Samovar

Sometimes it’s the regulations that are the problem.

Martin (erstwhile regulator)
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Old 8th Jul 2022, 5:45 pm   #17
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Default Re: Antique Belarusian Samovar

Just to add a bit more to the above, fitting a three core lead with an earth conductor adds another potential danger if the item is then connected to a purpose built and bought isolation transformer, as these nearly always have an earth connection from the input 13 Amp plug to the output 13 Amp socket. When using an isolation transformer such as this, the power cable needs to be two core ONLY, but fitted to a plug suitable for the socket on the transformer. If this socket is a standard 13 Amp square pin type, then there should be no earth connected to the earth pin on the plug on the end of the power cord from the appliance.

There really is only two answers to this and that's to either refuse the job or quote for a repair and a separate isolation transformer such as RS sells (or did sell - I haven't checked lately). I've got one from RS myself, but I've had it for years.

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Old 9th Jul 2022, 3:00 pm   #18
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Default Re: Antique Belarusian Samovar

The mains earth on an isolation transformer should not be connected to the output socket's earth pin. I know they usually are. When I worked at the BBC all RS isolation transformers were modified to comply with this.
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Old 10th Jul 2022, 9:48 am   #19
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Default Re: Antique Belarusian Samovar

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The mains earth on an isolation transformer should not be connected to the output socket's earth pin. I know they usually are......
YES! At last! I’m always trying to convince people that this is correct. The whole advantage of an isolation transformer is lost when people continually insist on connecting the earth of the transformer supply lead to the earth terminal on the isolated socket!

Anyway, let’s not start an argument on this here.
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Old 10th Jul 2022, 2:03 pm   #20
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Default Re: Antique Belarusian Samovar

No, you're both 'slightly' incorrect in this particular instance.

If you read my last post carefully I'm trying to explain it, but perhaps didn't make it clear enough.

It would be incorrect (and probably even illegal) to modify a purpose made safety item that you were going to sell on as a 'business', which the OP is, to a member of the general public. You can't have something with a thirteen amp 3 pin socket which doesn't have an earth connection connected to it, regardless of isolation transformer or no isolation transformer. There may be special 'in-house' commercial exemption for this sort of thing, as mentioned in post #12 and at such places as the BBC as mentioned in post #18, but you can't do it to an item you're supplying to Joe public. So that's why the isolation transformer has to be left exactly as supplied and the appliance has to be fitted with a two core cable with NO earth connected to the earth pin in it's three pin plug.

What we do in our own workshops with isolation transformers and disconnecting their internal bypass earths so that we can safely use them with ALL classes of equipment is quite another matter, but when supplying the public who may not know of the modification if the unit gets passed around is a whole different ball game.

I was wrong when I said that there were only two answers to the question, there's actually three in that the OP would be correct to just repair the unit back to original state if it can safely be done and leave it at that, but I would advise the customer verbally and also in writing on the invoice of the potential risks.
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