Just to elaborate on my previous post. Every so often, one channel or the other will revert to normal for a while - points to a dry joint but then I remember, the faults both started over the same weekend. My Thurlby/Farnell was sold by RS! It's brown. With rocker for damping. Central "quad" module (always used in isolated mode). I've shorted the sense/output bars internally as I was fed up of the links disappearing.
Hi Clive, So is your PSU a Thurlby PL320?
This sounds like a very strange fault because the PL320 is essentially two separate single power supplies bolted together. Are you sure that the mains input to the PL320 is good and fed from a good mains source ie not some sort of device that could be tripping.
I would check the mains plug socket on the wall and into the PL320 and check the mains cable for breaks. Any bad contact in the mains cable, plugs, sockets could cause this sort of intermittent on off behaviour.
Otherwise inside the PL320 the two single supplies share a common mains on/off switch (check this) and the central "quad" selector module. Its possible that the central "quad" has a bad contact, try switching the "quad" switches and try the supply in the series and parallel modes to see if the strange behaviour is still there.
These supplies are old and the mains input wiring is not up to modern standards so take care to work safely as regards shocks etc.
This sounds like a very strange fault because the PL320 is essentially two separate single power supplies bolted together. Are you sure that the mains input to the PL320 is good and fed from a good mains source ie not some sort of device that could be tripping.
I would check the mains plug socket on the wall and into the PL320 and check the mains cable for breaks. Any bad contact in the mains cable, plugs, sockets could cause this sort of intermittent on off behaviour.
Otherwise inside the PL320 the two single supplies share a common mains on/off switch (check this) and the central "quad" selector module. Its possible that the central "quad" has a bad contact, try switching the "quad" switches and try the supply in the series and parallel modes to see if the strange behaviour is still there.
These supplies are old and the mains input wiring is not up to modern standards so take care to work safely as regards shocks etc.
Hmm interesting, well you may well find that the actual voltage/current outputs are unaffected? Perhaps only the voltage and current measurements are being affected as measurements displayed are independent of power outputs.
It's a surprise to hear that the PL320 is susceptible to RF, perhaps there is some sort of other fault going on.
It's a surprise to hear that the PL320 is susceptible to RF, perhaps there is some sort of other fault going on.
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1) No, the output shuts down. I'm not worried by the fault. The RF presented at such short range is unusual. Won't normally happen.
2) I have put internal shorting links in my PSU so I don't need the shorting bars. I never need such accuracy that requires separate sensing leads.
I wish I'd known folk want these links as I've binned them!
3) I'm quite happy with the voltage and fine voltage controls. I do admit that the current limit could do with a "fine" control. i.e. a multiturn pot.
2) I have put internal shorting links in my PSU so I don't need the shorting bars. I never need such accuracy that requires separate sensing leads.
I wish I'd known folk want these links as I've binned them!
3) I'm quite happy with the voltage and fine voltage controls. I do admit that the current limit could do with a "fine" control. i.e. a multiturn pot.