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Ian French[_2_] Ian French[_2_] is offline
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Default Electric fence operation problem


"N_Cook" wrote in message
...
2 stage derivation of (should be) 1800V pulses.
Fence had failure in the first stage probably due to intermittant corroded
battery supply contact.
Anyway the 15A 60V 8N06 powerFET blew along with an associated double
diode
BAV23.
Replaced both and works to some extent. This FET has plenty of drive 5V of
pulses of repeat 3uS for the gate and about 3V ringing swing on the output
to the first step up transformer. I assume that is as to be expected,
never
having the chance to see hot-side SMPS drive scope traces.
But rectified output only climbs to about 1V of DC before the final stage
(unreadable marking) thyristor discharges that supply into the second step
up transformer, but of course not even enough to get a glow on a 110V
neon.
Doubling the C setting the 3uS pulses, to give longer repeat rate and that
intermediary voltage rises to about 3V but still not enough for any proper
final output. Adding more C and DC is then much less than 3V.
What would people expect the intermediary DC to be? obviously higher than
12V battery supply
Next stage would be disconnect the thyristor if that should be working but
leaky and draining the intermediary DC but any other ideas? Would explain
why the printing is very indistinct I suppose.
DC ohms of the airgap type transformers are
intermediary 0.1R//10.6R
HV 0.3R//29R which seem reasonable, ie not major shorted turns if any



Hi,

I found this schematic (circuit diagram) somewhere on the net, is it
anything like your one ?

http://www.electro-tech-online.com/a...ctricfence.jpg

Ian.