Parallax Power Supply 7345

pnichols wrote:


By the way, what MEX and myself mean by "temperature compensation" is a probe mounted in the air, close to the actual batteries, that measures the air temperature around the batteries and then feeds back through wires to the charger's circuits so as to have the actual charger output - no matter what stage the charger is in - automatically adjusted up or down. This minimizes the long term risk of damage to the battery(ies) in high air temperatures and more accurately optimizes the speed of charging in cold air temperatures.

I disagree with measuring the ambient air temp around the battery.
It makes no sense.

Please provide your source for this statement.

Battery temperature is measured on the posts of the battery.
That is the only place on a battery to get a true battery temperature reading and thus adjust the charge voltage.

It takes hours for a battery to equal changes to the ambient air temperature.

When charging takes place the battery temperature will rise. The greater the charge current the more rapid the battery internal temperature will rise. So if the ambient temperature is 40 deg f. and the battery's internal temperature = ambient then the Temp compensated charger will increase the charge voltage... As the internal temperature rises in the battery the charge voltage will begin to decrease, compensating for the increase in temperature of the battery.

Jim