Thermocouple ribbon cable - does it exist?

[Fred]

We currently have a number of thermocouple sockets which are currently
hand wired with thermocouple cable and crimped into a 15 way sub-
miniature D-Type.

Can anyone say if there was such a thing as a ribbon cable Type - K,
where alternate wires are of the appropriate metal type so one end
could go into an IDC connector held at a known temperature? This
would also save on our assembly time and we could also clamp this
ribbon cable to an aluminium block to reduce the effect of conduction
along the cable.

I would be grateful if anyone could help or point me in any direction.

 

[Eeyore]

We currently have a number of thermocouple sockets which are currently
hand wired with thermocouple cable and crimped into a 15 way sub-
miniature D-Type.

Can anyone say if there was such a thing as a ribbon cable Type - K,
where alternate wires are of the appropriate metal type so one end
could go into an IDC connector held at a known temperature? This
would also save on our assembly time and we could also clamp this
ribbon cable to an aluminium block to reduce the effect of conduction
along the cable.

I would be grateful if anyone could help or point me in any direction.

Umm, if you terminate you thermocouples onto ordinary copper ribbon cable
and re-terminate onto thermocouple wire at the other end wouldn't that
work - or would there a PD due to temp differences at both splice
junctions ?

Graham

 

[Fred]

Umm, if you terminate you thermocouples onto ordinary copper ribbon cable
and re-terminate  onto thermocouple wire at the other end wouldn't that
work - or would there a PD due to temp differences at both splice
junctions ?

Graham

Any "termination" or change of metal must be carried out at a known
and stable temperature. So the cable from the thermocouple socket (at
an unknown temperature) must of the same type as the cable from the
thermocouple.

It's essential that the thermocouple cable is then terminated into
copper at a known temperature. In our case this is a block of
aluminium where we can accurately measure it's temperature.

The existing D-Type socket plugs into our PCB which has precision
thermocouple amplifiers. This plug and the PCB is also in contact
with this aluminium block to ensure the "cold junction" is at this
measured temperature.

Many thanks for your post and interest.

 

[Glen Walpert]

We currently have a number of thermocouple sockets which are currently
hand wired with thermocouple cable and crimped into a 15 way sub-
miniature D-Type.

Can anyone say if there was such a thing as a ribbon cable Type - K,
where alternate wires are of the appropriate metal type so one end
could go into an IDC connector held at a known temperature? This
would also save on our assembly time and we could also clamp this
ribbon cable to an aluminium block to reduce the effect of conduction
along the cable.

I would be grateful if anyone could help or point me in any direction.

I have never heard of such a thing, and have questions about the
reliability of an IDC connector attaching to Chromel and Alumel solid
thermocouple wires when they are designed for stranded copper. But if
your quantities justify it you could check with specialty cable
manufacturers like Cooner Wire, or find a harness assembler which
could make your harness and connector assembly with automated
equipment at lower cost than hand assembly.

 

[Fred]

I have never heard of such a thing, and have questions about the
reliability of an IDC connector attaching to Chromel and Alumel solid
thermocouple wires when they are designed for stranded copper.  But if
your quantities justify it you could check with specialty cable
manufacturers like Cooner Wire, or find a harness assembler which
could make your harness and connector assembly with automated
equipment at lower cost than hand assembly.

I doubt the quantities we need would be worthwhile for a special run.
I accept what you say, but it seems the easiest way to kill 2 birds
with one stone, one being ease of assembly and the other to clamp the
cable between two blocks of aluminium.

Many thanks for your reply.

 

[Paul M]

We currently have a number of thermocouple sockets which are currently
hand wired with thermocouple cable and crimped into a 15 way sub-
miniature D-Type.

Can anyone say if there was such a thing as a ribbon cable Type - K,
where alternate wires are of the appropriate metal type so one end
could go into an IDC connector held at a known temperature? This
would also save on our assembly time and we could also clamp this
ribbon cable to an aluminium block to reduce the effect of conduction
along the cable.

I would be grateful if anyone could help or point me in any direction.

Take a look at this.

http://www.freepatentsonline.com/5111002.html

 

[Fred]

Take a look at this.

http://www.freepatentsonline.com/5111002.html

Thanks for the link. The ribbon refers to a single conduction which
is wide but very think. I was hoping someone may have made a multi-
conductor ribbon. I can get cables with multiple conductors but they
won't do the same job.

 

[whit3rd]

We currently have a number of thermocouple sockets which are currently
hand wired with thermocouple cable and crimped into a 15 way sub-
miniature D-Type.

Can anyone say if there was such a thing as a ribbon cable Type - K,

Type K is nickel-alloy wiring, Chromel and Alumel in the old
brandname scheme, and doesn't crimp well. You'd do better
with acid flux and soft solder, or welding.

Omega sells multipair cable, but it isn't 'thermocouple' cable,
but the lower-precision 'thermocouple extension wire' cable.
See <http://www.omega.com/ppt/pptsc.asp?
ref=4KX_MULTIPAIR_CABLE&Nav=temh10>

For best results, even the connector pins should be of the
thermocouple material, and only screw-barrier and some of the
familiar thermocouple plugs are really available in that
form. The easiest quick-connect to find (like, at Radio
Shack) is the tube-with-a-setscrew type wire splice.

I think (not completely sure) one can gang multiple plugs
side-by-side to make a complex connector. The sockets
stack, and the plugs have a through-hole that allows one to
bolt them together. These are listed as type NMP or SMP
connectors...

 

[Archimedes' Lever]

Thanks for the link. The ribbon refers to a single conduction which
is wide but very think. I was hoping someone may have made a multi-
conductor ribbon. I can get cables with multiple conductors but they
won't do the same job.

You should talk to those Mylar/Kapton "flex circuit" makers.

They could likely laminate your wires into a cable form.

You could actually do it yourself if you can find the kapton sheet
stock and an appropriate adhesive or surface prep that allows you to
laminate your runs inside it. Double space it, and fold the ribbon in
half to get the offset right for the pin spacing.