Author Topic: Workbench electrical safety advice  (Read 7256 times)

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Offline nightfire

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Re: Workbench electrical safety advice
« Reply #50 on: December 19, 2022, 07:30:51 pm »
Yes, exposed bends are not nice to look at, but the usual way it is done. There are things you *could* do, like premade 90 degree tubes or flexible tube to wrap, but thats a bit more ugly in most cases. In areas with some condensation it is also mandated that in some cases you should do some lower point/bend so that water will collect there and drip down, and you have some free air circulation in the straight tubes to prevent moisture buildup.
 

Online themadhippy

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Re: Workbench electrical safety advice
« Reply #51 on: December 19, 2022, 08:08:49 pm »
Quote
There are things you *could* do, like premade 90 degree tubes
or learn how to make bends in pipe ,for plastic all you need is a spring and a knee.
 
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Offline Monkeh

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Re: Workbench electrical safety advice
« Reply #52 on: December 19, 2022, 08:11:14 pm »
Quote
There are things you *could* do, like premade 90 degree tubes
or learn how to make bends in pipe ,for plastic all you need is a spring and a knee.

And for the last week or so a hot air gun...
 

Online nctnico

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Re: Workbench electrical safety advice
« Reply #53 on: December 19, 2022, 09:43:38 pm »
Quote
There are things you *could* do, like premade 90 degree tubes
or learn how to make bends in pipe ,for plastic all you need is a spring and a knee.
And strong hands. Watching my family member working with plastic pipe always amazed me how he managed to create all kinds of odd shapes to make the piping look nice. My own pipe bending results don't look so nice  :'(
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Black Phoenix

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Re: Workbench electrical safety advice
« Reply #54 on: December 20, 2022, 04:07:30 am »

I have been chatting in Discord about this with one of our German members, and it seems DEU regs on containment differ considerably from UK ones. I still think it looks terrible to have exposed bends!

I don't see how glaring it is. It's common to see such in Industrial applications both in Germany, Portugal (my country) and even China (were I'm currently stationed).

It meets and in some cases (China) suppass the regs.

In UK is different, but for me the most outrageously thing is how home installation in the UK is done, with the CUs under stairs or high in the ceeling or inside cabinets in kitchens and cables under floorboards, in some case just laying down there. And the ring circuits...

Give me the inside wall PVC pipes with singles and junction box on each room every single day and radial circuits as it's done in Europe and China. Ahh and let's not talk about the cluster fuck it is the Australian CUs (just look at Dave's video about it).

CUs should be in a easy accessible, at a proper height level without needing steps or going inside a cramped place to do any work. But if it meets regs of the country then it's just a different way of doing it.
 

Offline AVGresponding

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Re: Workbench electrical safety advice
« Reply #55 on: December 20, 2022, 11:27:00 am »

I have been chatting in Discord about this with one of our German members, and it seems DEU regs on containment differ considerably from UK ones. I still think it looks terrible to have exposed bends!

I don't see how glaring it is. It's common to see such in Industrial applications both in Germany, Portugal (my country) and even China (were I'm currently stationed).

It meets and in some cases (China) suppass the regs.

In UK is different, but for me the most outrageously thing is how home installation in the UK is done, with the CUs under stairs or high in the ceeling or inside cabinets in kitchens and cables under floorboards, in some case just laying down there. And the ring circuits...

Give me the inside wall PVC pipes with singles and junction box on each room every single day and radial circuits as it's done in Europe and China. Ahh and let's not talk about the cluster fuck it is the Australian CUs (just look at Dave's video about it).

CUs should be in a easy accessible, at a proper height level without needing steps or going inside a cramped place to do any work. But if it meets regs of the country then it's just a different way of doing it.

It is in the regs that consumer units, panel boards, distribution boards, should be readily accessible for maintenance and testing purposes.

The BS7671 regs are not a legally binding document though, just guidance for making safe and reliable installations, ie, if you follow the guidance and someone dies from a problem with your installation, you're unlikely to be prosecuted. If you deviate and someone dies however, you're in trouble.
If you deviate and can provide a good engineering explanation/risk assessment for how and why your deviation is as safe as the preferred method, and why it's necessary, you'll get it signed off (as long as the Clerk of Works/Installation Tester is knowledgeable enough to understand, not guaranteed...).
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Offline Monkeh

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Re: Workbench electrical safety advice
« Reply #56 on: December 20, 2022, 03:43:51 pm »

I have been chatting in Discord about this with one of our German members, and it seems DEU regs on containment differ considerably from UK ones. I still think it looks terrible to have exposed bends!

I don't see how glaring it is.

.. well, for us 'containment' means containing, not covering some parts of and leaving all the difficult bits open because it's too much bother to get it right.
 

Online themadhippy

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Re: Workbench electrical safety advice
« Reply #57 on: December 20, 2022, 04:27:50 pm »
yea it looks crap,but even in the uk ,that particular installation would comply with the regs as the cables are double insulated, all its doing is offering  additional mechanical protection.
Quote
And for the last week or so a hot air gun..
:-DD ya big girls blouse,rubbing  yer hand up and down the pipe a few times gets it warm enough.
« Last Edit: December 20, 2022, 04:32:56 pm by themadhippy »
 

Offline AVGresponding

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Re: Workbench electrical safety advice
« Reply #58 on: December 20, 2022, 04:45:47 pm »
yea it looks crap,but even in the uk ,that particular installation would comply with the regs as the cables are double insulated, all its doing is offering  additional mechanical protection.
Quote
And for the last week or so a hot air gun..
:-DD ya big girls blouse,rubbing  yer hand up and down the pipe a few times gets it warm enough.

Yes, it's not outside the regs, it just looks shit. It would look better just tower clipped.

Having to wank the tube is extremely tedious, especially if you have many bends to do.
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Offline Monkeh

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Re: Workbench electrical safety advice
« Reply #59 on: December 20, 2022, 04:47:52 pm »
yea it looks crap,but even in the uk ,that particular installation would comply with the regs as the cables are double insulated, all its doing is offering  additional mechanical protection.

I don't know, I'm not convinced that qualifies as good workmanship!

I was also under the impression PVC conduit (and trunking) was not classed as mechanical protection, although let's be honest, we all consider it better than bare cables to be bumped and scraped. Metal conduit just isn't needed in most cases.
 

Online nctnico

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Re: Workbench electrical safety advice
« Reply #60 on: December 20, 2022, 04:55:41 pm »
yea it looks crap,but even in the uk ,that particular installation would comply with the regs as the cables are double insulated, all its doing is offering  additional mechanical protection.

I don't know, I'm not convinced that qualifies as good workmanship!

I was also under the impression PVC conduit (and trunking) was not classed as mechanical protection, although let's be honest, we all consider it better than bare cables to be bumped and scraped. Metal conduit just isn't needed in most cases.
Over here PVC conduit can be bought in 2 grades: 'regular' (typically yellow) and 'impact resistant' (typically grey). The 'impact resistant' variation is typically used to guide sheathed cable (with the bends open indeed) where the regular variant is used inside walls, cement floors and piping along a ceiling (for example) to carry individual wires. When individual wires are used, the pipes are supposed to cover these end-to-end to inside the junction boxes.
« Last Edit: December 20, 2022, 05:00:28 pm by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline nightfire

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Re: Workbench electrical safety advice
« Reply #61 on: December 20, 2022, 05:21:22 pm »
The BS7671 regs are not a legally binding document though, just guidance for making safe and reliable installations, ie, if you follow the guidance and someone dies from a problem with your installation, you're unlikely to be prosecuted. If you deviate and someone dies however, you're in trouble.
If you deviate and can provide a good engineering explanation/risk assessment for how and why your deviation is as safe as the preferred method, and why it's necessary, you'll get it signed off (as long as the Clerk of Works/Installation Tester is knowledgeable enough to understand, not guaranteed...)
The german VDE standards are also privately developed recommendations how to do stuff- but there is a referral from the law (ยง49 enWG) that the people erecting installations have to work accordingly to the acknowledged rules of technology- and this is considered to be followed if people work accordingly to VDE standards.
 

Offline vad

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Re: Workbench electrical safety advice
« Reply #62 on: December 21, 2022, 06:06:19 am »
What is some advice you would give to someone who is setting up a bench from scratch? Do I need GFCI outlets? An AFCI breaker? Something I should do to ground my workbench? Anything else?

Currently I have planned:

1. A separate 20A breaker for the workshop area, shared between lights and all the outlets in the room.

It is always a good idea to have GFCI protection in workshop.

Lights may or may not be on GFCI protected circuit, depending on local code. In Massachusetts, where I live, it is against the code to wire every lighting outlet behind GFCI: "210.70(D): GFCI Protection of Lighting Outlets in All Occupancies: The operation of a single GFCI device shall not deenergize all lighting outlets in a given area."

AFCI is debatable. I do have AFCI breakers on two out of three 20A circuits in my workshop. My DIY Controleo3-based reflow oven used to trip AFCI, so I am now plugging it into GFCI-only circuit. I also had incidents when conducted EMI from misbehaving DUT (SMPS) was tripping the AFCI.
« Last Edit: December 21, 2022, 06:11:41 am by vad »
 

Offline nightfire

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Re: Workbench electrical safety advice
« Reply #63 on: December 21, 2022, 11:35:31 am »
In germany we have similar regulations, but here it is ok to wire them half/half behind 2 RCDs.
I would also read this regulation in a similar way- the aim is not to have everything in the dark when a group RCD trips.
 
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