What was this bruned component in my T1000s power supply?

[Murvel]

So while taking apart and cleaning my t1000s I heard something loose in the powersupply and something that looked like a little stone fell out
I took apart the supply and eventually found this mysterious part. It has clearly been very hot at some point and is all cracked to pieces.

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It has been very warm at some point in time

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Here is its cremated remains. Looks to have been about 8mm in diameter and about 7mm long with the connections at the round ends.

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And this is the board serial number

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I have no schematics for this supply so i can not look it up what i could be. I know where to find a couple other similar machines so one possibility is that i go and take apart another one and check what it is. Maybe i could even borrow a supply.

I am just suspicious of what caused that part to fail. And if it could have damaged anything else in the process. At a glance everything else looks fine at least, with no obvious signs of heat or burning

[Murvel]

A little update:
Today I went and checked another, low serial number machine of the exact same spec/version as this one.
It had the same model power supply and it turned out to have the exact same issue! Same component was aslo burnt to a crisp and it already looked to have been opened up and fixed once at some point. The pcb even had a hole burned thought the board under the component. My board is luckily only a bit burnt. So still no luck in identifying what the toasty little component used to be

I find it curious the same component is burnt out in both machines. And in both everything else, at least visually, looks perfectly fine. So maybe a design fault of the supply itself? Or since both machines seem to come from the same place maybe something happened at that office to cause them both to go?

But for now, I now seem to be pretty much stuck in trying to repair this without any schematics

[Murvel]

Good morning,

the defective component is a thermistor (NTC) to limit the starting current.
I suspect that other components are defective: rectifier, primary capacitors, power transistor, etc.

[Murvel]

the defective component is a thermistor (NTC) to limit the starting current.
I suspect that other components are defective: rectifier, primary capacitors, power transistor, etc.

Thank you very much for the answer! My next plan of action was actually to message you since i had a feeling that if someone knows what it could be, it would be you I also had a friend suggest it might be one but we were not sure.
Would you happen to know what value thermistor it should be?

I will go through it and measure what i can and maybe it would be good to also change the capacitors while im at it. I think that after 44 years their time has maybe come

Since the machine was made in the 80s, i don't think it cant have been operational for that many years. So i think it is very odd that this component had gone the same way in both machines. Could this have been a common problem?

[Murvel]

Thought I would update with another question since, at the moment, i am pretty much stuck with no further possibility to get this running with my current reverse engineering skills.

Are there at all any schematics available for this power supply at all? As i do not have access to the archive i can not check for myself. To my understanding this is sort of uncommon model that is quite different to other T1000S machines and the only manuals i have been able to find online are all of a totally different design.

But so far everything else seem to be measuring out normal other than one diode that have a bit odd reading compared to two others of the same type. It is mostly this thermistor that i cant find any information on at all. In other designs the thermistor seem to be of the PTC type, but as DrT1000 mentioned this one should be a NTC type i am now more confused. To me a NTC would make sense for this purpose. Im unsure of how much of a redesign siemens did with this PSU but its possible this works in some other way.

Also, are the power supplies interchangable between different models/versions of the T1000S? There is the possibility that I could get my hands on a different one for now

Any help would be much appreciated!