18-12-2016, 12:09 PM
(18-12-2016, 10:22 AM)AlanBeckett Wrote: Perhaps it would be best to move that Post to the Battery changing Thread
Which thread?
(18-12-2016, 10:22 AM)AlanBeckett Wrote: By the way, most Farnell Bench PSUs don't have any Reverse Polarity protection so connecting a Battery to the Output when it's set to lower than the Battery Voltage destroys a lot of the Transistors.
Yes, I've reported on that in the past and published a simple mod to fix it.
You have to go over the set voltage by quite a bit, as the failure mechanism is exceeding the ~7V reverse VBE breakdown voltage of the driver transistor (VT5 in the E series, for example). Unlikely to happen here.
It usually happens when you apply an external voltage when the PSU is powered down. A power cut while charging a battery is "fun", as you can imagine what happens to the battery when the mains returns!
