Converter In-Rush Thermistors etc, UPDATE -4
UPDATE on 17 Nov, Update 2 on 22 Nov, Update 3 on 16 Jan 14, Update 4 on 19 Oct 14. --------------- In a recent thread there was mention of how you can wreck your gizmo (in my case a converter) ...
Forum Discussion
BFL13 wrote:
"Then from this info above, it seems that clamping on first before start up would make the thermistor need to charge the capacitors plus the load? Is that not worse? I am confused about that."
Two things that may be happening when clamping on first.
1. The converter starts to charge the battery slowly as the input voltage comes up. This gives the thermistor time to heat up and the resistance lower before the charge current comes up to full. This lowers the requirements of the thermistor.
2. There is a small time delay from when power is applied and the battery starts charging. This is the same as above. This gives the thermistor time to heat up and the resistance lower before the charge current comes up to full.
The problem seems to be a cold thermistor not a hot one!
"Then from this info above, it seems that clamping on first before start up would make the thermistor need to charge the capacitors plus the load? Is that not worse? I am confused about that."
Two things that may be happening when clamping on first.
1. The converter starts to charge the battery slowly as the input voltage comes up. This gives the thermistor time to heat up and the resistance lower before the charge current comes up to full. This lowers the requirements of the thermistor.
2. There is a small time delay from when power is applied and the battery starts charging. This is the same as above. This gives the thermistor time to heat up and the resistance lower before the charge current comes up to full.
The problem seems to be a cold thermistor not a hot one!
