Russellc,
We have deduced that the PEM that is installed has Failed. If you bypass the failed PEM with a temporary switch and fuse is everything normal
within the amp itself.
You stated that the amps have worked for years, I have worked for years but I sure have some bad days.
We have deduced that the PEM that is installed has Failed. If you bypass the failed PEM with a temporary switch and fuse is everything normal
within the amp itself.
You stated that the amps have worked for years, I have worked for years but I sure have some bad days.
No. If the fuses are the cause they will also fail in another fuse holder. It would help if you could reply to suggestions/questions.
1. Do you know the fuse brand/series?
2. Can you test the fuse with a load and PSU (in a cheap fuse holder) ?
3. Can you measure if the fuse is 5 x 20 mm?
For a correct follow up you need to determine if it is the IEC inlet or the fuses that have caused this issue. It would not be wise to trust either one of them at this point.
Exactly what I'm complaining about. I use one of those for each channel in new builds, not to replace the ones in the schurter unit, just so I can power up one channel at time.
Do t know what they are like then, but now are cheap plastic with beer can metal inside.
Russellc
Do t know what they are like then, but now are cheap plastic with beer can metal inside.
Russellc
Not all fuse holders are created equal.
https://www.digikey.com/en/products/detail/eaton-electronics-division/BK-HTB-52I-R/1024132
https://www.digikey.com/en/products/detail/eaton-electronics-division/BK-HTB-66I-R/1024146
High temperature, flame retardant thermoplastic meets UL 94 V-0
https://www.digikey.com/en/products/detail/eaton-electronics-division/BK-HTB-52I-R/1024132
https://www.digikey.com/en/products/detail/eaton-electronics-division/BK-HTB-66I-R/1024146
High temperature, flame retardant thermoplastic meets UL 94 V-0
Pretty standard. Even the subject has those features. No manufacturer wants to be in the news with products that caught flames.
But even when made of McDonalds plastic cups a 10A rated one should be able to be used to 10A.
Maybe it were unreliable fuses bought on Aliexpress. I guess we’ll never know.
But even when made of McDonalds plastic cups a 10A rated one should be able to be used to 10A.
Maybe it were unreliable fuses bought on Aliexpress. I guess we’ll never know.
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Just a thought here, Russell…
I’m not familiar with this model Schurter, are the wire connections on the back designed to accommodate Faston female connectors?
If soldering hookup wires to this PEM, is it possible to overheat and distort the plastic that would result in a misalignment of the fuses when the drawer is installed?
I’m not familiar with this model Schurter, are the wire connections on the back designed to accommodate Faston female connectors?
If soldering hookup wires to this PEM, is it possible to overheat and distort the plastic that would result in a misalignment of the fuses when the drawer is installed?
This is a very intriguing thread. Is it possible these amps were exposed to large temperature fluctuations at times when humidity was high? Thinking about it a little wildly, could condensation have occurred at any point leading to galvanic corrosion? Only the parts in a tiny enclosed space show this corrosion, where moisture can get trapped. This is why you may not see corrosion on any other interfaces.
They obviously got really hot. A poor electrical contact would be one likely cause of this heat. Corrosion being a possible cause of a poor connection. Moisture is probably the biggest culprit to cause corrosion. I just like tossing out wild ideas to think "outside the box". If it worked fine for years, clearly something changed over time.....pointing to something like corrosion, which takes a lot of time to manifest.
This is where ZM says "this is why I don't use spade connectors and instead solder direct".
They obviously got really hot. A poor electrical contact would be one likely cause of this heat. Corrosion being a possible cause of a poor connection. Moisture is probably the biggest culprit to cause corrosion. I just like tossing out wild ideas to think "outside the box". If it worked fine for years, clearly something changed over time.....pointing to something like corrosion, which takes a lot of time to manifest.
This is where ZM says "this is why I don't use spade connectors and instead solder direct".
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Soldering spade connectors 6.3 or 4.8 mm and this while the fuses are still in the fuse holders would be a double user error.
The versions meant for soldering wires have much smaller contacts for shorter soldering.
The versions meant for soldering wires have much smaller contacts for shorter soldering.
Not at all, maybe you are. Like always I try to find a root cause why stuff breaks down if only to prevent people getting hurt (home fire is a terrible phenomenon). You wrote "this is why I don't use spade connectors and instead solder direct". If that has been done (take a look around here and see how often this is done) erroneously to the 6.3 or 4.8 mm faston connector type while the fuses were still there both the fuse holder and the fuses would have been weakened considerably. This could very well be a root cause for defects in time. If it is a solder version things are different. That version is designed to be soldered.
It exists in both versions, either with solder lugs or "6.3 or 4.8 mm blade terminals" as they call it. The pictures do not show which exact one was used.
Corrosion because of condensation is unlikely as there is a hole to prevent such. Also the device likely is used in a normal home and not in an igloo.
It exists in both versions, either with solder lugs or "6.3 or 4.8 mm blade terminals" as they call it. The pictures do not show which exact one was used.
Corrosion because of condensation is unlikely as there is a hole to prevent such. Also the device likely is used in a normal home and not in an igloo.
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Zero connection. You misunderstood. It was a joke is all based on known bias to using spades by ZM. Apologies for corrosion 🙂...I mean confusion. I was not implying they are linked in any way other that corrosion takes time.
I am simply proposing the failure is caused by condensation and then subsequent corrosion. Per evidence from visual inspection.
Please don't discount this. I personally think it's the likely cause of the failures. Could I be wrong, of course, but it sure seems like a very plausible cause.
I am simply proposing the failure is caused by condensation and then subsequent corrosion. Per evidence from visual inspection.
Please don't discount this. I personally think it's the likely cause of the failures. Could I be wrong, of course, but it sure seems like a very plausible cause.
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Wouldn't know that known bias. I used faston professionally and when branded ones are used (like those by Klauke, AMP/TE) they are OK. There are way better connectors out there but faston has gained a large market share because they are cheap. Cheap wins.
In DIY faston connectors are misunderstood like many simple things. I stopped commenting on that as it seems generally accepted many are using 4.8 and 6.3 mm faston connectors incorrectly. Often by soldering or using the wrong size for the cable like the blue version for 1.5 mm2 cable, both crimping and soldering, Aliexpress versions etc.
Fault finding can be done by excluding factors. I just wanted to contribute to that as prevention of home fires is a serious thing but it was enough (or too much 🙂) it seems.
In DIY faston connectors are misunderstood like many simple things. I stopped commenting on that as it seems generally accepted many are using 4.8 and 6.3 mm faston connectors incorrectly. Often by soldering or using the wrong size for the cable like the blue version for 1.5 mm2 cable, both crimping and soldering, Aliexpress versions etc.
Fault finding can be done by excluding factors. I just wanted to contribute to that as prevention of home fires is a serious thing but it was enough (or too much 🙂) it seems.
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Apologies.....just a joke. ZM prefers soldered joints is all. We can't solder fuses into fuse holders. (Well, maybe we can, but no one tries to do that). I personally like faston connectors, but don't tell ZM I said that please 😉 I do solder on my chassis safety earth faston so it can't be removed. (I have already said too much....I might be in trouble with ACME police now)
To be clear......There is clearly observed corrosion on the base of the fuse holder where the bottom of the fuse engages/contacts the fuse holder in the pictures. What caused this rust? Any chance that corrosion is linked to the heat related failure?
I'm probably misguided. I just like to think "out of the box" with troubleshooting.
Any chance we can get pics of the fuses that were in the failed fuse holders?
I'm probably misguided. I just like to think "out of the box" with troubleshooting.
Any chance we can get pics of the fuses that were in the failed fuse holders?
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Corrosion also can occur when reinforced plastics melt/burn and give off fumes/gasses. In electrical failures of proportions the parts are usually corroded after the fact.
Still it can be a factor. We don't have enough information and the more input (by anyone!) the higher the chance the root cause is discovered. Any fire or failure that can be prevented is one to count.
Still it can be a factor. We don't have enough information and the more input (by anyone!) the higher the chance the root cause is discovered. Any fire or failure that can be prevented is one to count.
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You're probably right. Corrosion was caused by the overheat. I'm 99% wrong most of the time. It's my gift.
Not sure why I even try to propose possible issues with my noob background. I'll leave it up to the experts to figure out. I'm just interested in the final conclusion so I can avoid the same issue. Apologies for the ridiculous off the wall, wildly crazy thoughts that always get me in trouble.
Not sure why I even try to propose possible issues with my noob background. I'll leave it up to the experts to figure out. I'm just interested in the final conclusion so I can avoid the same issue. Apologies for the ridiculous off the wall, wildly crazy thoughts that always get me in trouble.
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