My original post had a misleading typo: my capacitors weigh 10Kg not
10lb each. Sorry. They sound very similar to the CDE ones from Henry
that Jim describes.
I have tested each unit for temperature rise when carrying 3A ripple
current at 50Hz, using a carefully fused variac on UK mains. I clamped a
temperature probe to the case for hands-free measurement. The bottom
line is I can't see any temperature rise in one hour - confirmed by hand
after removing the mains connection. I don't doubt these things are not
purpose made for HT PSU applications but as far as ripple current goes
they seem fine.
I do not yet have the means to charge the caps to 3KV in finite time for
hi-potting so I will need to scratch build a PSU using a junk box
transformer I have.
Thanks to everyone for your help.
73, Alan G3XAQ
On 15/04/2015 14:38, Jim Thomson wrote:
## They will run fine at 3 kv no load. Dunno about 2A ripple current though.
They are light. Mine were from henry radio, made by CDE. 8 x 4 x 12 and
weighed
30 lbs each, rated at 42 uf @ 4500 V. Mount them vertically.
Also insulate them from any metal chassis, and metal sidewalls....and also from
the 2nd oil cap. IE: Treat them like hv electrolytics. If you see oil
stating to leak
around the insulators, stop using them. Your caps are no doubt pulse type
rated caps,
and they usually have high ESR. On any pulse rated oil cap, don’t runt them at
any more than
60% of their stamped rating.
Jim VE7RF
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