This Fuse Never Gonna Blow!

by Editor on March 12, 2015

On a recent electrical inspection job I was intrigued when I saw that the cut out fuse carrier had no seal and was red rather than the usual black.  I removed the carrier to check the rating of the HRC fuse and found that there was no fuse, but instead it had a piece of metal pipe. Therefore no overload protection to the incoming side of the consumer’s installation, mains tails etc. . Potentially very dangerous!

I guess this was a temporary solution to a blown main fuse that never got to be made permanent. Maybe the red fuse with a solid pipe link is a standard piece of kit for DNO electricians for situations where no HRC fuse is required. So if you ever see a red cut out fuse don’t take it for granted that there’s the correct size fuse inside.

I replaced the pipe link with a 60 amp BS88 / 1361 HRC fuse as show above.

Prices for HRC & Cartridge Fuses

{ 5 comments… read them below or add one }

Graham J. Ellis March 29, 2015 at 21:26

Cautionary note!!!

“I hope I did the right thing…” — Well, yes and no. It all depends how much further investigation you did first!

As Steve says, a red device in the position of the cut-out fuse (which is indeed generally a piece of pipe the dimensions of a 1361 fuse, but rarely a pair of straight legs with a link bar between) is the “clear indication” from the DNO that this device is not fused, and exclusively used when the actual supply protective device is up-stream. Most commonly seen in shared accommodation (“residential” as opposed to “domestic” installations), such as a block of flats, where each premises has a CCU but the “service head” (meter and cut-out-that’s-not-a-cut-out) are in a common service riser/enclosure, often locked to the residents so that the DNO can disconnect a resident without having to go back to source. Sometimes (say in sheltered accommodation) the meter and fake-cut-out are in the flat’s own enclosure. The common part is that each set of tails will lead back to another riser/cabinet/etc. where there will be a neat set of real cut-out fuses (or sometimes a few “master” cut-out fuses each feeding several sets of tails) near the main incomer to the block.

Before replacing this red device with an appropriately populated black one (or, in this instance, the solid link inside with an appropriate fuse and then *clearly labelling* the red warning device to indicate that it is now a *fused link*!) you should fully investigate whether this property is in fact fed from a common shared service somewhere up-stream. If truly not, it may be true that some daft electricity board man in times past has needed to reconnect the property, not had a fused link in his van, and yet still had one of these unusual solid links fetching about, and forgot to return to properly complete the job… Would be very odd, though, and should be properly investigated.

kung March 29, 2015 at 17:57

That’s not a fuse it’s a link normally fitted in flats the header fuse carrier is black they fit the black tip inside the flat and the cutout fuse normally in a meter room phone s&s they will confirm. Hope that helps as I used to work for Southern Electric as a metering engineer.

jon March 29, 2015 at 17:22

Hi, the carrier is red to signify it has no fuse in! They are only intended for use where there is a cutout fuse prior to it. Commonly in flats where a MSDB/ ryefield unit is used.
They are fitted to enable the supply to be isolated not to provide overload or short circuit protection.

Editor March 29, 2015 at 16:30

Thanks for the info Steve. I hope I did the right thing in replacing the blank with a fuse, but I reckon that you can never have too much protection especially with the state of much of the old incoming supply equipment nowdays.

steve white March 29, 2015 at 16:13

I have come across these before they are indeed blanks fitted by the DNO where the main protective device is further down the line. Years ago when voltage operated trips where all the rage these where often used.

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