In article ,
Mike Gilmour wrote:
When you've tightened down a bare cable to a binding post wait a few
hours then retighten - you'll always get a bit more clamping power
without overtightening the connection. The same applies to 'choc bloc'
terminal strips - when they are fully tight, wait - then tighten again.
(The clamped cable does relax over a short time).

Good grief. Considering the number of such terminals in the average house
carrying a great deal more current, I'm surprised there's not fires
everywhere. ;-)

--
*Born free - taxed to death *

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
In article ,
Mike Gilmour wrote:
When you've tightened down a bare cable to a binding post wait a few
hours then retighten - you'll always get a bit more clamping power
without overtightening the connection. The same applies to 'choc
bloc' terminal strips - when they are fully tight, wait - then
tighten again. (The clamped cable does relax over a short time).

Good grief. Considering the number of such terminals in the average
house carrying a great deal more current, I'm surprised there's not
fires everywhere. ;-)

The number of mains plugs I've removed that are very very loose is amazing.

--
"Get a paper bag"

"Tim S Kemp" wrote in message
...
Dave Plowman (News) wrote:
In article ,
Mike Gilmour wrote:
When you've tightened down a bare cable to a binding post wait a few
hours then retighten - you'll always get a bit more clamping power
without overtightening the connection. The same applies to 'choc
bloc' terminal strips - when they are fully tight, wait - then
tighten again. (The clamped cable does relax over a short time).

Good grief. Considering the number of such terminals in the average
house carrying a great deal more current, I'm surprised there's not
fires everywhere. ;-)

The number of mains plugs I've removed that are very very loose is
amazing.

--
"Get a paper bag"



Not only mains plugs I've just selected two ring mains sockets at random and
one terminal was loose and the others could take a tightening.
the loose wire had not arced because the two conductors were twisted
together. Some sunny day I'll go around the lot.
How's your mains?.......is that a burger frying? Don't lose any sleep over
it ;-)

In article ,
Mike Gilmour wrote:
Not only mains plugs I've just selected two ring mains sockets at random
and one terminal was loose and the others could take a tightening. the
loose wire had not arced because the two conductors were twisted
together.

Twisting single strand mains cable is frowned on these days. With the
standard two cables into each ring main socket it isn't needed. For a
socket which is a spur, and therefore only one cable, I double over the
conductor.

--
*Caution: I drive like you do.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Tim S Kemp wrote:
Good grief. Considering the number of such terminals in the average
house carrying a great deal more current, I'm surprised there's not
fires everywhere. ;-)

The number of mains plugs I've removed that are very very loose is
amazing.

Well, yes. Not properly tightened in the first place.

--
*If love is blind, why is lingerie so popular?

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Tim S Kemp wrote:
Good grief. Considering the number of such terminals in the average
house carrying a great deal more current, I'm surprised there's not
fires everywhere. ;-)

The number of mains plugs I've removed that are very very loose is
amazing.

Well, yes. Not properly tightened in the first place.

--
*If love is blind, why is lingerie so popular?

Dave Plowman London SW
To e-mail, change noise into sound.

I knew I'd seen something in print about terminal block tightness - This is
a quote from a doppler log installation manual (obviously non metric.... but
American nevertheless) just one from all the pointless manuals I still hold
on to... (I really must have a clear out one day) :-)

"Tighten PCB mounted terminal blocks to 3 inch-pounds of torque. Always
tighten terminals twice - First initially, then once again after 5 to 10
minutes. This prevents the terminal block from loosening due to relaxation
of the metal in the wire"

That's good enough for me....

Mike

In article ,
Mike Gilmour wrote:
"Tighten PCB mounted terminal blocks to 3 inch-pounds of torque. Always
tighten terminals twice - First initially, then once again after 5 to 10
minutes. This prevents the terminal block from loosening due to
relaxation of the metal in the wire"

3 in.lbs? Easy to exceed that with a jeweller's screwdriver...

That's good enough for me....

Perhaps. Doubt it has any relevance to speaker terminals, though. They're
likely to need checking once in a while through vibration.

--
*Learn from your parents' mistakes - use birth control

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Mike Gilmour wrote:
"Tighten PCB mounted terminal blocks to 3 inch-pounds of torque. Always
tighten terminals twice - First initially, then once again after 5 to 10
minutes. This prevents the terminal block from loosening due to
relaxation of the metal in the wire"

3 in.lbs? Easy to exceed that with a jeweller's screwdriver...


Yep, a mini-block on a pcb, its just an example - thats all.


That's good enough for me....


Perhaps. Doubt it has any relevance to speaker terminals, though.

Very relevant I would have thought with bare wire connections.


They're likely to need checking once in a while through vibration.

Exactly!


--
*Learn from your parents' mistakes - use birth control

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Mike Gilmour wrote:
When you've tightened down a bare cable to a binding post wait a few
hours then retighten - you'll always get a bit more clamping power
without overtightening the connection. The same applies to 'choc bloc'
terminal strips - when they are fully tight, wait - then tighten again.
(The clamped cable does relax over a short time).

Good grief. Considering the number of such terminals in the average house
carrying a great deal more current, I'm surprised there's not fires
everywhere. ;-)

--
*Born free - taxed to death *

Dave Plowman London SW
To e-mail, change noise into sound.


Its just informing HiFi folk (who are generally fussy) that they can tighten
down connections some more - no harm in that. Considering houses are not
subject to constant vibration this hardly applies to domestic ring mains,
cookers etc. Actually there are quite a few incidents of arcing and
localised heating due to loose 13A socket terminal connections but because
the area being metal clad and grounded it generally goes no further (ask any
leccy)

Mike

In article ,
Mike Gilmour wrote:
Actually there are quite a few incidents of arcing and localised
heating due to loose 13A socket terminal connections but because the
area being metal clad and grounded it generally goes no further (ask any
leccy)

Yes - I've come across it several times. Due to inadequate tightening in
the first place. I'm inclined to think even deliberate by some
electricians to make more (chargeable) work for them later. However, I've
not known of any of the things I've installed - quite a few over the years
- give trouble in this respect. I do them up until they groan. ;-)

--
*Why is the man who invests all your money called a broker? *

Dave Plowman London SW
To e-mail, change noise into sound.