TO-3P Insulator cover

[daveyk]

Is there any place in the US that I can purchase: TO-3P Insulator cover - TOP3 - L:28.5mm - W:17.5mm - H:5.8mm - 0.8W/mK - 4kV

Here's what they look like:
https://www.ebay.com/itm/TO-3P-Insulator-cover-TOP3-L-28-5mm-W-17-5mm-H-5-8mm-0-8W-mK-4kV/312796561381?hash=item48d420bfe5:g:2IEAAOSwwlVdnJ7q

$10+ Plus high shipping.

I can't find them in the USA in EBAY, DIGIKEY, or MOUSER.

Thanks a bunch!

[T3sl4co1l]

At a glance, doesn't seem to be much selection, but this is a match and quite available, nice: https://www.digikey.com/product-detail/en/t-global-technology/THINC33-TO247-28-5-17-5-5-8-0-3/1168-1957-ND/3878146

Tim

[daveyk]

Thank you!  I searched Digikey and couldn't find anything.  I didn't know what to search for I guess - lol; thank you.

[T3sl4co1l]

Yeah... I've ran across them before, not sure how many there are.  If there are other types or brands, they aren't listed under any descriptive labels.

Tim

[David Hess]

When you need an insulated cover for a TO-3 power transistor, then you really need it.  I had a ground wire fall down behind a 12 volt 50 amp power supply and it touched the case of the TO-3 driver transistor which resulted in blowing out the low current control winding on the transformer.

[daveyk]

In the case of this switching power supply, the main filter capacitor after the switching transformer most likely shorted (it is now 100% open, high ESR, no capacitance reading), took out the rectifying diode (600v inverse voltage, I think), and the main switching FET 2SK2601. Compared to another working supply, that transformer looks a little brown (over-heeated).  It is probably bad, but I still want to try to replace the cap, diode and switching FET (which I needed that insulating sleeve for), more or less for shits and grins to see if I could fix it.

The particular power supply is the only one ever tested for use in that UT system.  Others may work, but you go to pay attention to noise radiation.  I can only find that power supply used now.  So I order a couple and I order all the caps to re-cap them before putting them in to use.  I ordered 10 of those rare insulating sleeves just in case they tear taking the supplies apart to re-cap them.

[Grandchuck]

Would something such as described in the attached link be a possibility?

https://www.alliedelec.com/m/d/e4e619c16107fbf1651a92ccad8e4f4b.pdf

[daveyk]

I just ordered 10 of these for 40 cents each: https://www.digikey.com/product-detail/en/t-global-technology/THINC33-TO247-28-5-17-5-5-8-0-3/1168-1957-ND/3878146

Now based on your heat shrink suggestion, I don't think so.  In addition to insulation, it has to have heat transfer parameters. These "hoods"/"covers" are made from that blue heat transfer tape.

Dave