I have a couple of henley blocks on my incoming electrics board
located after the meter. The henley blocks have seals on them. (The
incoming electrics run through the meter, through henley blocks to the
I need to change my consumer unit, so I would like to open the henly
blocks up and connect the new CU tails.
Is it illegal to open these seals even though they are placed after
Thanks in advance for your help,
On Mon, 19 Jan 2004 07:52:12 UTC, email@example.com (Mark) wrote:
MY feeling is that in a lot of cases, Henley blocks have seals put on
them 'because there is a place for them'.
However, you make no mention of any isolator, so I would guess that they
are there to make people think twice about opening them, since there is
no real way of making them 'dead' short of pulling the main fuse. It is
dangerous to work on the tails live, the problems not just being with
Of course, if you're pulling the main fuse anyway, that's different (but
that would be breaking a seal too, and you didn't mention that one). The
general consensus seems to be that the leccy board don't worry much
about it these days.
Again, you could have an isolator immediately after the meter, but you
don't mention it.
There isn't an isolator, but I was under the impression that it would
be reasonably safe to do this live, since you would only be working
with one wire, which would only become live once it inserted into the
On 19 Jan 2004 08:56:20 -0800, firstname.lastname@example.org (Mark) wrote:
Whilst I've worked with live wires quite often I think I'd draw the
line at working with a live wire which had an almost limitless current
capacity and no human-friendly protective devices downwind.
Slightly different matter when you've got an RCD on the circuit
protecting your arse.
Sending email to my published email address isn't
guaranteed to reach me.
I guess provided the first thing you do is remove the one tail from
one henley block and then put the cover back on and tape over the
hole. Then do the other it wouldn't be to bad as you don't have a free
end of 25mm cable waving about with 240v on it.
Getting the new tails in might be fun 25mm cable is not the easiest
stuff to work with. I know I was swearing fairly loudly at the last
lot of 16mm I had to deal with and that was ona fully dead system. Not
sure I'd want to do it with this big exposed lump of brass directly
connected to the mains in front of me.
Pull the fuse, the boards don't appear to care anymore. What would you
prefer 6' under or a slapped wrist?
Dave. pam is missing e-mail
On Mon, 19 Jan 2004 22:11:32 +0000 (GMT), "Dave Liquorice"
True, last one I did was a 3 phase job, phoned Scottish Power, "Just
cut the seals and do it, phone us when you're done and we'll come out
and reseal it."
Most new installations seem to have isolators.
IIRC I did suggest that but they weren't interested. Not sure there
was room without major alterations. Huge old house, 3 ph supply,
electric underfloor heating. Only private house I've ever seen with a
If its a Scottish Power area Dataserve will usually sort them out for you
(the new name for the metering dept.), but if you need a cutout change
then the relevant operations dept (Power Systems) for the area will fit
one at the same time as changing it.
The preferred method is one of the above, but if its a rush job then
*sometimes* we can arrange another way (without saying how, and it
doesn`t include cutting the seals yourself !)
Please add "[newsgroup]" in the subject of any personal replies via email
* old email address "btiruseless" abandoned due to worm-generated spam *
I had just this situation a week or two ago. Took seals off henley block
after meter and on the main fuse before it.
I then changed the CU. However I noticed the elec company's short cable from
the incoming cable to main fuse had perished insulation.
So I called them out to replace it. When they came they made no mention of
the seals being removed.
Neither did the meter reader
Replaced both my dodgy consumer units by withdrawing the tails from the unsealed
Henly block - if that is what the Bakelite box with two stacked busbars is
called. I used a seriously insulated screwdriver to undo each tail in turn and
then refitted the cover. Removed and replaced the consumer units and mounting
board. Remade new tails and then refitted them to the Henly. All without
removing the company seal.
This was all done after watching the bod from the Lecy board replace the company
fuse by hammering the tar filled remains off the incoming cables (live) without
any protection apart from the wooden handle of his hammer (and plenty of
PS he didn't seal my Henly block.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.