Identifying Broken Connections on an Extensional Viscosity Measuring Instrument

[watson.894]

What is this component in the middle with the two broken connections? It is on an instrument for measuring extensional viscosity that is not working. It looks like a power amp and a wire wound resistor on the same board got real hot. Don't know if there is any relationship to the two broken connections pictured.

 

[phinds]

It's a fuse chip with four fuses, two of which have blown

 

[watson.894]

It's a fuse chip with four fuses, two of which have blown

Thank you very much! However, I am having a heck of a time finding similar parts on the internets. Do you have any suggestions on where to find it or how to search for it?

Regards,
Lucas

 

[Daz]

That looks more like an old-fashioned DIL jumper to me.
http://home.kpn.nl/a.dikker1/museum/diljumper.html

 

[phinds]

Thank you very much! However, I am having a heck of a time finding similar parts on the internets. Do you have any suggestions on where to find it or how to search for it?

Regards,
Lucas

Really? What did you try? Googling for "8-pin fuse chips" got a TON of hits

 

[anorlunda]

In an event, the fuses blew for a reason. If you replace them before fixing the cause, the new fuses will probably blow also.

 

[watson.894]

That looks more like an old-fashioned DIL jumper to me.
http://home.kpn.nl/a.dikker1/museum/diljumper.html

What is it for? The picture you attached was an exact match. This is instrument was bought new 1991.

 

[watson.894]

Really? What did you try? Googling for "8-pin fuse chips" got a TON of hits

What Daz posted looked like an exact match. If it was a fuse, would the top blow off like that?

 

[Daz]

A Dil jumper was used as a low-cost alternative for a DIP switch. They were used for configuration settings that aren't expected to change after manufacture. You plug (or solder) the thing in and then punch or snip the straps as required.

 

[maltman]

very doubtful that it is a fuse.. it would be hard to make accurate current control in that structure
I believe that it t is a programable ( well one time) jumper block.
A cheaper version of a DIP switch

 

[phinds]

What Daz posted looked like an exact match. If it was a fuse, would the top blow off like that?

I assumed that it was topless so the fuses could be replaced, but it could be, as others have suggested, a jumper chip. If it IS a jumper chip then something REALLY drew too much current.EDIT: yeah, now that I look, I don't see any "topless" fuse chips so I guess it must be a jumper chip that really got overloaded.

 

[CWatters]

Is it possible those two jumpers were cut at the factory when it was made?

 

[CWatters]

I would try tracing the circuit in that area. How thick are the PCB traces that connect to the jumpers?

 

[rootone]

Is it possible those two jumpers were cut at the factory when it was made?

The plastic looks melted under the two broken links, so that suggests probably not.

 

[anorlunda]

Why would jumpers narrow down to a thin bottleneck shape like that? If I was going to make a fuse out of foil, a shape like that would be perfect. You could fine tune the amp rating of the fuse by how narrow the bottleneck is.

 

[Averagesupernova]

My guess is that it is something that is one time programmable.

 

[davenn]

EDIT: yeah, now that I look, I don't see any "topless" fuse chips so I guess it must be a jumper chip that really got overloaded.

no, specific jumpers are cut to provide a certain function
and when used in this fashion, jumpers can always be rejoined and other combinations cut

I have used this method often in PLL radio systems where I want to set the n=counter number to give the correct frequency

there are many other uses

Dave

 

[phinds]

no, specific jumpers are cut to provide a certain function
and when used in this fashion, jumpers can always be rejoined and other combinations cut

I have used this method often in PLL radio systems where I want to set the n=counter number to give the correct frequency

there are many other uses

Dave

Oh, it looked to me like a blown fuse. Guess you're right, though.

 

[davenn]

Oh, it looked to me like a blown fuse. Guess you're right, though.

a trap for young players ( tease, tease knowing you are my senior )

 

[phinds]

a trap for young players ( tease, tease knowing you are my senior )

What? I can't be more than 30 or 40 years older than you

 

[davenn]

hahaha --- one needs a sense of humour to survive this world
Thanks buddy

Friday is here and it's time to go home from the salt mine yipeee

here's part of one totally wrecked bit of gear I dealt with today ... $15,000 GPS receiver very wet and corroded
you can still see the water droplets on those ribbon cables

 

[phinds]

Well, just remember that Friday is POETS day.

Piss
On
Everything,
Tomorrow's
Saturday

 

[meBigGuy]

I assumed they were programming jumpers and were opened with a hot soldering iron.