I've just been testing my 36V throttle LEDs on my 48V battery pack with the aid of a variable resistor.
By simply adjusting the resistance until I had a reading of exactly 75% of the battery voltage
(36/48=0.75) I came up with this:
A 36V throttle running on 48V SLA batteries requires a resistance of approx 740 Ohms in line for it to work correctly.
Fitting a 1K variable resistor would enable it to be fine tuned to suit the type of battery being used. Now when I load the motor and pull the voltage down, the lights actually start to go out like they should!
And the gauge doesn't get so warm now either.
A 500 Ohm variable resistor could be used for fine tuning the 48V gauge to better suit the GM 48V lithium "rack pack".
Just thought this information might be useful to some of you.
Alan