Record players and radiograms. Deck earthing?

[hayerjoe]

Hello again

I've just picked up an old Australian Kreisler radiogram from 1947. It has a rubber 2 wire flex, I will replace this with a 3 wire flex and attach the earth to the chassis (I've confirmed it's not a live chassis) but my question is should I earth the BSR record changer as well? in fact this is really a generic question, I have a fair few radiograms from the 50's and 60's none have the record changers earthed. Should I earth them? I've read conflicting advice on this, but what are people's thoughts?

My opinion is they are 240v and largely have a metal body well exposed to humans whose hands touch it all the time, and whilst the 240v motors are fairly well isolated on rubber grommets etc surely they are at risk of giving a shock if the 60 year old power supply wire is dodgy.

Look forward to your replies.

Joe

[Edward Huggins]

Well it is normal practice to earth the turntable deck plate assuming your Radiogram's chassis is fully mains isolated and uses a 3 core lead - and that you do not create an "earth loop". Trial and error will determine this.

[Techman]

All day and no replies - I think there could be a good reason for that.

I don't know what the laws/regulations regarding this sort of 'modification' are in Australia, but here in the UK it's strictly speaking illegal to modify the mains input to an appliance from the original design, such as fitting an earth where one wasn't fitted before. It may seem ridiculous not to make something electrically safer than it was originally, but that's the way it is, and there's some reasoning behind it. Here in the UK, modifying an electrical item in such a way would change its state and would mean that it would have to have government type approval, which could cost thousands, and then because of a lot of other factors it still wouldn't comply to todays standards, so you can't ever make it something it isn't or make up you own rules to suit yourself, although there's nothing to stop you breaking those rules and take ownership and responsibility for what you do.

So I'm not telling you what you should and shouldn't do, it's entirely up to you what you decide to do, and it could well be that the regulations are completely different in your country, I wouldn't know - I don't even know all the 'ins and outs' of how it all works myself in this country, other than you shouldn't fit an earth to a vintage radio etc. if no earth was fitted originally. You can fit like for like, say if an original rubber twin flex is rotten, then it's fine to replace it with a modern version of the same thing.

If a forum member told you that you should replace the twin mains cable with a three core type and earth the gram, then technically they could be responsible for advising you to do something illegal and against regulations, but it's also possible that there are no such regulations in your country. If someone advised you that it was OK to fit an earth to a radio that was originally made without an earth (this has got nothing to do with live or transformer isolated chassis or anything else), it's just about keeping to original design. The biggest problem is unskilled or unqualified people fitting earths in an incompetent way and making the appliance more dangerous than it was before and trust me, I've seen some dangerous examples.

Lastly, thousands of folk working on vintage equipment replace two core mains cable with three core and make a proper job and never have a problem, but it doesn't make it right, although arguably it makes it safer if done correctly. I've even done it myself, mainly because I happened to have a length of three core cable to hand at the time, when an original two core cable has been cut off or otherwise damaged, but if an original two core cable is fitted as original and is in good condition, then I'll always leave as original, or if damaged I'll replace it with more two core if I've got it to hand. The big difference is that I have a paper qualification that I can wave in front of the judge to justify what I've done in fitting an earth in the very unlikely event that the worst happened - and hope for the best!

You obviously don't have an official qualification, as you wouldn't need to ask the question in the first place (good that you did, though), but what I would say regarding what you want to do is consider one or two things - A continuity test will show whether there's a continuous earth connection between deck components and the main gram chassis. However, you then need to consider what constitutes that earth connection and would it be good enough to carry a fault current to earth capable of blowing a fuse, or would that earth connection just heat up and cause a fire without blowing a fuse, OK you might have an RCD or similar that would trip anyway. So you fit a good earth between deck components and gram chassis, but then you may have hum problems due to an earth loop, and so it goes on...you'll probably want to go and lay down in a darkened room after all that lot and I wouldn't blame you!

So the choice is yours - you do it, you own it. Good luck.

[Techman]

Just to note - Edward's post #2 has only just appeared in the last few minutes, yet he posted it this morning...I personally find this very irritating, as it sometimes causes unnecessary confusion - and I know it's not his fault.

[Radio Wrangler]

Some very good advice from Techman.

Electrical safety of period equipment s a bottomless mire of worries. In general, you can leave it as it is, and any blame for its design attaches to the period people who made it. You could get blamed for having it in use in a degraded condition, especially f it was being used by your children, visitors, or if you sold it. You are probably OK doing repairs that replace like with like... say a new mains calbe of the same style but in good condition.

Once you make any changes it gets a lot more complicated. You become responsible for the design changes because you did them, but you can, in some countries, become suddenly responsible for the whole thing meeting all current safety, design and proof testing requirements. THe cost of having the testing done in an accredited test house would buy several top end hifi systems.

You need advice from someone local, who knows Australian regulations.

Oh, and if you do something that relies on an RCD protected mains socket, how do you ensure that no-one in future will ever connect it to an unprotected one?

We're trying to keep you safe from legal entanglements.

David

[GrimJosef]

Originally Posted by Techman

... I don't know what the laws/regulations regarding this sort of 'modification' are in Australia, but here in the UK it's strictly speaking illegal to modify the mains input to an appliance from the original design, such as fitting an earth where one wasn't fitted before. It may seem ridiculous not to make something electrically safer than it was originally, but that's the way it is, and there's some reasoning behind it. Here in the UK, modifying an electrical item in such a way would change its state and would mean that it would have to have government type approval, which could cost thousands, and then because of a lot of other factors it still wouldn't comply to todays standards, so you can't ever make it something it isn't or make up you own rules to suit yourself, although there's nothing to stop you breaking those rules and take ownership and responsibility for what you do ...

As I understand it it's not at all illegal in the UK to make changes to equipment. What is illegal is to sell unsafe equipment (even if you sell it privately) and, in the case of equipment manufactured after a certain date, to sell equipment without a valid CE mark. If you modify equipment then you cannot rely on any previous CE mark. You need to mark it anew before you can sell it. The government isn't involved in this, other than as a legislator saying you have to do it and putting in place the standards you have to meet. You are the one who has to certify that you've met the standards. Many manufacturers choose to support their certification by paying an approved test house (these are private sector companies) to test the equipment for compliance.

It's not a specific legal issue, but you may want to consider how operating modified equipment might affect any insurance cover you have (in particular for fire) and also what your liability might be if someone should get a shock.

Cheers,

GJ

[Restoration73]

Technically the main benefit of connecting the turntable to amplifier signal earth is to
reduce or eliminate mains hum. Especially as the pickup wiring is adjacent to or threaded
through the turntable metal arm and chassis. In this case no additional mains earth cable should be attached to the record deck metalwork as no improvement would result.

[dave walsh]

There are no recorded examples of injury from unearthed record decks as far as I can see or even live chassis sets! One Forum member built a very advanced and expensive shack in his garden, a long way from any neighbour but to his credit, felt obliged to notify the local authority! He had to demolish it. He said to me. You were right! Having said that, we know from previous threads that the Australian Mains system is [literally] another country. In France, Spain or the USA for example, you can more or less build whatever you want wherever you want as long as it meets the regulations! Go figure

Dave W

[hayerjoe]

Well I woke up this morning expecting to find the usual swag of helpful information and there were 166 views and no comments! so I did think obviously a legal minefield for people. So many thanks to those who did answer, and I fully understand what was said

I tell you why I asked, with my 1947 radiogram I got a free 1946 radio. The radio had a 3 core flex and I opened it up and it was earthed to the chassis, it was obviously a retrofit as it was bit ugly soldering and the wire looked 1960s. The radiogram on the other hand had just 2 core.

Legislation in Oz is pretty severe, but many people ignore it, a good example of by stopping people doing the most basic electrical things you lose the confidence of the public so that they attempt things actually too complicated and I guess kill themselves in the process. I'm quite cautious, I'm no electrician, and i do nothing electrical on the radiograms I get other than bulb/fuse changes, cleaning, cartridge swaps etc, but I've now found a radio enthusiast who's also an electrical safety tagger, so I now get him to replace rat eaten capacitors, power supplies etc (something I probably could do but I won't). And it was that person who said we should replace that cord with a 3 core and earth it. and I thought that is something I can definitely do even if it's perhaps not to the letter legal

But now I'm thinking leave it as-is (I mean replace like for like) as I don't want to introduce any mistake that may hurt someone in the future