Plugs less safe then fused connection unit?

[John D v2.0]

According to 2.22 of this

A plug isn't good enough to isolate a boiler. Not to correct standard. Sounds funny, you're never going to elbow a plug and plug it back in by mistake, but an fcu can do easily!
Is that just because fcu is easier to lock off? And does anyone ever lock them off when working on a boiler?

 

[Dan Robinson]

It is one of "those" rules.

 

[ericmark]

Does seem odd, you can only lock off the line with a fused spur, but with a plug you lock off line and neutral so it would seem safer, the only reason I can see for FCU is the earth is left connected.

 

[bernardgreen]

Bonding continuity check ( at 1:50 into the video ) found satifactory just because he could see the clamp was within 600 mm of the outlet. No check that the clamp had a cable with continuity to the MET ( Main Earth Terminal )

the only reason I can see for FCU is the earth is left connected.

True but if the Live and Neutral are disconnected ( plug removed ) then the boiler does not need an Earth. And anyway there will be a path to earth via the pipe work and bonding

 

[oldbutnotdead]

Only logic i can see is that old one about someone seeing a 13A socket and assuming they can unplug whatever is in it and plug their phone charger in. This does happen (best one i had was a visiting 'sound engineer' needed to charge his Iphone. Instead of asking us for a 4 way he unplugged something. Which turned out to be the supply cable to the ups running the sound desk...)

 

[JohnD]

Not to correct standard.

no doubt he mentioned the paragraph number of the regulation in his report to the landlady, so she has the advantage of us in being able to see what it actually says.

 

[picasso]

Personally I reckon he is talking boolocks but you never know

 

[gas112]

Absolute nonsense the only thing is the plug cannot be in a switched socket , so to isolate you have to remove plug and not just turn switch off as it may still be live if socket is wired wrong

 

[nwgs]

Less than 300mm is ncs. This lad is keen

 

[ianmcd]

As @gas112 says if it was a plug into a switched socket most would just switch it off and not remove the plug, the socket that the plug is plugged into is only single pole disconnection a fused spur is dual pole disconnection, a plug can be used into an unswitched socket so that the plug has to be removed

 

[gas112]

no mention of 1 min temp stabilisation just says next bit is 2 mins , on putting nipple back in and turning on no leak detection fluid used on nipple or ecv and inlet , cooker test no mention of checking oven bypass rate ...
nit picking but if he wants to mention a plug at least do or mmention mandatory things

 

[John D v2.0]

I reckon this is more of a marketing video than educational, he's trying to sound trustworthy rather than comprehensive.
But i take the point that the functional switch on many sockets is not an approved means of isolation, but non electricians may not appreciate that and so rely on it. Thanks all.

 

[Dan Robinson]

Not all spurs are double pole either

 

[John D v2.0]

no doubt he mentioned the paragraph number of the regulation in his report to the landlady, so she has the advantage of us in being able to see what it actually says.

Presumably in gas regs the manufacturer's instructions carry more weight than in the electrical regs, and you know what manufacturers are like for asking for local fcus on everything.
When we moved in, the boiler isolator here was a single pole light switch wired into a 15A rewireable fuse carrier for the lighting circuit that actually had a piece of 1mm conductor bridging it. So a local fcu would have made a lot of sense to be required in that situation.

 

[John D v2.0]

Not all spurs are double pole either

Electrically, if you're isolating something on a standard domestic single phase TN supply, single pole isolator is fine. This is because the neutral is physically connected to the supplier earth.
That's exactly how mcbs isolate a circuit when they trip, single phase only. And the supplier can pull the cutout fuse which is counted as isolation.
Yes the polarity must be correct, but incorrect polarity is a dangerous fault on an electrical installation regardless and must be confirmed as part ofoany electrical work.
Having said all that, domestic main switches must isolate both line and neutral as they are for unskilled people to use.