Author Topic: POMONA Test Leads - repeated failure  (Read 1801 times)

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Offline k1mgy

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POMONA Test Leads - repeated failure
« on: May 11, 2018, 02:21:37 pm »
The POMONA 6275 test lead set is great for probing micro-size circuits.  These are my go-to for most work.  However, over the past year or so I've had to replace them three times.  Each time, I've repaired the problem only to have the leads fail again and end up in the dumpster.

Today one of them failed, and of course led me on a wild goose chase searching for a rail that showed up as intermittently present!

This is more of a bitch, than looking for a solution - although if anyone can recommend a better engineered test lead set with very tiny spring loaded probe tips, I'm listening.


 

Offline metrologist

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Re: POMONA Test Leads - repeated failure
« Reply #1 on: May 11, 2018, 02:50:09 pm »
that looks like a break right at the end of the strain relief. Maybe add a couple pieces of shrink tube to extend the strain relief and provide a little more support. I'd probably stagger a couple, few inch long pieces.
 

Offline k1mgy

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Re: POMONA Test Leads - repeated failure
« Reply #2 on: May 11, 2018, 03:19:53 pm »
Doing so will just cause the break to happen further down.  The bend occurs when holding the probe.  Gravity pulls on the lead and creates a bend near the end of the strain relief.  I know, because my previous repairs failed again, right past the point where I had made the repair and where my heat shrink strain relief terminated.
 

Offline grifftech

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Re: POMONA Test Leads - repeated failure
« Reply #3 on: May 11, 2018, 03:26:20 pm »
Heat shrink the entire thing ;D :D ;)
 

Offline k1mgy

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Re: POMONA Test Leads - repeated failure
« Reply #4 on: May 11, 2018, 03:47:44 pm »
In a blast furnace.
 

Offline Samogon

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« Last Edit: May 11, 2018, 04:20:25 pm by Samogon »
 
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Offline k1mgy

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Re: POMONA Test Leads - repeated failure
« Reply #6 on: May 11, 2018, 04:21:16 pm »
Perfect!  Will give these a go.
 

Online floobydust

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Re: POMONA Test Leads - repeated failure
« Reply #7 on: May 11, 2018, 05:33:51 pm »
The Pomona leads, great but tips break if you bump them. The spring-loaded ones (6342) have an aluminium tube and a crappy contact resistance. 6341 kit $70 at Digikey! :rant:

I copied the Russians and make SMT probes from office pens, using a sewing needle and silicone wire. You can also use a PCB test pogo pin, as they have a spring.
Just glue it into a gutted pen ink cartridge tip. This is for the poor but actually works great.

 
 

Offline Smith

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Re: POMONA Test Leads - repeated failure
« Reply #8 on: May 11, 2018, 06:16:57 pm »
I have been using the Pomona 6341 probes for quite some time now, and I never had any troubles with hem. My colleagues have started using them too, they work like a charm for SMD. For bigger stuff I do still use my Fluke Tl175's.
Trying is the first step towards failure
 

Online MarkL

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Re: POMONA Test Leads - repeated failure
« Reply #9 on: May 12, 2018, 09:24:11 pm »
I have a set of the Pomona 6275 probes too, and have encountered the exact same problem with wire fatigue right at the strain relief.

I cut back the strain relief, cut out the break, and resoldered the ends with flexible heat-shrink to form a new strain relief with a more gradual curve.  I'm sure it will happen again at some point, but this has been holding for about 5 years now.

I bought a second set as a backup in case I'm in the middle of something and don't want to stop to deal with probe issues.

The ProbeMasters look ok, but the grip area seems too far from the tip.  It's not like I need all that distance when probing low voltage.  I think I'd rather have better positioning precision.
 

Offline chris_leyson

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Re: POMONA Test Leads - repeated failure
« Reply #10 on: May 12, 2018, 09:49:21 pm »
The Fluke TL910 test leads are not much better, the wire keeps breaking "inside" the probe ! After the second set of probes failed I hacked one apart. Inside the probe body there is a brass barrel to hold the replacable probe tips and the wire is soldered onto the end of the barrel and that is where it fails. If fluke had used a bit of common sense and crimped the wire they might have been decent probes.
I ended up replacing the probes with Hirschmann needle point probes with 2mm sockets and they're still going good. Hirschmann 973 531-100 and -101. Works out a lot cheaper than Fluke probes and more importantly they don't go open circuit.
 

Offline k1mgy

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Re: POMONA Test Leads - repeated failure
« Reply #11 on: May 12, 2018, 09:54:20 pm »
The Hirschmann look to be very sweet.  Unfortunately there appears to be a lack of US distribution, although Newark will import them for a little extra:

http://www.newark.com/c/test-measurement/test-leads-test-probes/test-lead-probe-kits?brand=hirschmann-testmeasurement
 

Offline andy2000

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Re: POMONA Test Leads - repeated failure
« Reply #12 on: May 13, 2018, 02:42:53 pm »
I've been relatively satisfied with Huntron MicroProbes.  They have very sharp adjustable tips, and the probe end can be disassembled completely if the wire ever breaks.  Their main weakness is that the plastic screw in tip can break just above the threads if it's handled roughly.  There are some cheap MP-10s on ebay right now if you don't need safety banana plugs. 
 

Offline k1mgy

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Re: POMONA Test Leads - repeated failure
« Reply #13 on: May 13, 2018, 03:52:26 pm »
Having used the very first Tracker years ago, I remember those probes.  But don't recall if they were gold plated.

A Dave Jones video demonstrated (not very scientifically, but convincingly nonetheless) that the gold plated tips are superior.

I've gone ahead and ordered up a pair from ProbeMaster, and will report back here once I've used these a bit.
 

Offline particleman

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Re: POMONA Test Leads - repeated failure
« Reply #14 on: May 13, 2018, 06:44:35 pm »
I have the Fluke TL81A lead set. So far they are the best leads I have ever had.
 

Offline Samogon

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Re: POMONA Test Leads - repeated failure
« Reply #15 on: May 13, 2018, 08:27:03 pm »
I have the Fluke TL81A lead set. So far they are the best leads I have ever had.
We are talking about micro spring loaded leads. Different breed cows
 
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Offline particleman

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Re: POMONA Test Leads - repeated failure
« Reply #16 on: May 13, 2018, 09:36:58 pm »
I have the Fluke TL81A lead set. So far they are the best leads I have ever had.
We are talking about micro spring loaded leads. Different breed cows

Figured the IC probes that come in that kit would work. I guess not. My bad
 

Offline Samogon

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Re: POMONA Test Leads - repeated failure
« Reply #17 on: May 13, 2018, 11:24:11 pm »
I have this set
Needle point are ok to reach tight spaces and isolation helps a lot,
But to probe dense IC is hard because they flex and your grip is too high.
 

Offline tooki

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Re: POMONA Test Leads - repeated failure
« Reply #18 on: May 15, 2018, 07:21:42 am »
The Fluke TL910 test leads are not much better, the wire keeps breaking "inside" the probe ! After the second set of probes failed I hacked one apart. Inside the probe body there is a brass barrel to hold the replacable probe tips and the wire is soldered onto the end of the barrel and that is where it fails. If fluke had used a bit of common sense and crimped the wire they might have been decent probes.
It’s no surprise the Fluke leads aren’t any better than the Pomona: it’s the same product. Fluke owns Pomona. They sell the same items under both brands.
« Last Edit: May 15, 2018, 11:20:47 am by tooki »
 

Online Whales

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Re: POMONA Test Leads - repeated failure
« Reply #19 on: May 15, 2018, 07:44:52 am »
I copied the Russians and make SMT probes from office pens, using a sewing needle and silicone wire. You can also use a PCB test pogo pin, as they have a spring.
Just glue it into a gutted pen ink cartridge tip. This is for the poor but actually works great.

This sounds interesting, but I'm having troubles with search keywords.  Do you have a link?


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