Tripping Mains circuit - how to isolate?

[John B]

Ken Taylor scrobe on the papyrus:

..
..

Glad you have (or soon will!) find the problem. Rather than gaffer
tape, get hold of some heatshrink tubing, the type with the 'glue' in
it - much better weatherproofing.

Cheers.

Ken

Self-amalgamating tape is great. We used miles of it in permanent cable
installations for outside broadcasts. Never had a problem.

RS stock number 494-433.

 

[Terry Pinnell]

Glad you have (or soon will!) find the problem. Rather than gaffer tape, get
hold of some heatshrink tubing, the type with the 'glue' in it - much better
weatherproofing.

I like heatshrink tubing for neat joints (although I've never used any
containing glue). But for joints of several wires of different sizes
and condition, some with outers, possibly also using a screw-type
connector, it's not versatile enough.

 

[I.F.]

I like heatshrink tubing for neat joints (although I've never used any
containing glue). But for joints of several wires of different sizes
and condition, some with outers, possibly also using a screw-type
connector, it's not versatile enough.

Spread a little hot melt glue on the join before sliding the heatshrink
sleeve over it, if you do it right the heat applied to shrink the sleeve
makes the hot melt glue spread either side of the join and makes a
completely moisture proof seal.

 

[I.F.]

:

[snip]

A ring main has a single source (the fuse for that circuit) its simply
both
ends of the ring are connected to the fuse, the ring main can have any
number of radial spurs.

That modifies the problem slightly. A fault on one of the radials can be
detected by fusing or putting some sort of overcurrent indication on
each. But for a problem on the ring itself, both sides of the loop will
carry part of the overcurrent. So either the ring must be split or
overcurrent detection placed in the middle of the ring must also sense
power direction.

Hi Paul...

For the benefit of the OP, may I add that if he does go the route
of fusing or GFI'ing one of those spurs, that it still won't
necessarily tell him anything.

The one that opens is going to be the one that is either/or more
sensitive to a ground fault, or failing that the one that's faster

Take care.

Ken

Its probably worth mentioning that ELCBs rarely actually measure ground
current, its more common to measure the difference between the currents
flowing in live & neutral - obviously if there's more current in the live
wire than the neutral, then it must be going somewhere it shouldn't! This
eliminates the need to put an additional component in the earth lead (which
could fail!) It senses a fault current flowing to earth via a person and
also works on 2 wire appliances with no earth wire.

 

[Ken Weitzel]

Spread a little hot melt glue on the join before sliding the heatshrink
sleeve over it, if you do it right the heat applied to shrink the sleeve
makes the hot melt glue spread either side of the join and makes a
completely moisture proof seal.

Hi...

Fantastic idea; thanks for sharing it

Take care.

Ken

 

[I.F.]

Hi...

Fantastic idea; thanks for sharing it

Take care.

Ken

It takes a little practice to get it right - at first you might find the
sleeve splits quite easily!

 

[Rich Grise]

It takes a little practice to get it right - at first you might find the
sleeve splits quite easily!

Do "hot-melt" glues come in different temperature ratings? I've seen pre-
glued heatshrink things - actually, they were little boots, that you'd put
over a twisted connection, much like a wire nut, and they already had the
meltable glue inside them.

ISTR the number 105C, i.e., at 105 degrees C, the heatshrink loosens and
shrinks; I'd think I'd want the glue to melt before the tubing gets much
hotter than that.

Then again, I've also seen coax terminators made out of two wires, a
couple of rings of solder, and heatshrink. It must have been some very
low-melting solder, but they were pretty kewl to install too.

Thanks,
Rich

 

[Don Lancaster]

Do "hot-melt" glues come in different temperature ratings? I've seen pre-
glued heatshrink things - actually, they were little boots, that you'd put
over a twisted connection, much like a wire nut, and they already had the
meltable glue inside them.

ISTR the number 105C, i.e., at 105 degrees C, the heatshrink loosens and
shrinks; I'd think I'd want the glue to melt before the tubing gets much
hotter than that.

Then again, I've also seen coax terminators made out of two wires, a
couple of rings of solder, and heatshrink. It must have been some very
low-melting solder, but they were pretty kewl to install too.

Thanks,
Rich

There are all sorts of ultra low temperature melting alloys, some of
which will melt in your hand.

Small Parts is one source.


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com

 

[I.F.]

There are all sorts of ultra low temperature melting alloys, some of which
will melt in your hand.

Small Parts is one source.


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com

Pure metallic sodium might melt in the hand - only trouble is, it'd melt the
hand too!