This forum is in read-only mode. Please continue to browse, but replies are disabled for now. Why?

Choosing the right power switch for scooter 2 battery packs

Hi, I have 2 scooters using the same type of battery and i have dismantled one so I can use it's pack for the other. I have no idea which power switch to get and how to connect them to the system as both of them already have charger connectors connected to them.

Are you installing a second battery pack on the scooter and need a switch to select which battery pack supplies power to the scooter?

Yes I am ! But both of these batteries have a charger connector attached to them, is there a way for me to charge both of them through 1 connector ? May I know which switch to use ?

If the vehicle has a transfer switch or power switch that only allows one of the battery packs to be used at a time, then the battery packs will need to be recharged with two different battery chargers.


The reason for this is that each battery pack will discharge to a different Voltage level since they not being used at the same time, and if they were both recharged with the same charger then the Voltage levels between then would become unbalanced and one battery pack would become overcharged while the other battery pack would become undercharged. This over and under charging would damage both battery packs and cause them to need to be replaced sooner than necessary.


However if both battery packs will be used at the same time without a switch to select which one provides power to the vehicle, then provided that the Voltage of both battery packs was equalized before installing, and that both battery packs have batteries that are the same brand and age and size, an adapter that plugs into both battery pack's charger ports and has one charger port could be made so both battery packs could be recharged at the same time with one battery charger.

Guess I will go with charging the batteries separately. Which switch should I be using and how do I go about wiring it ?

 To recharge two battery packs separately with one battery charger our item # SWT-154 is the one to use. Here is a wiring diagram showing how to wire it for this purpose.



When the switch is in the middle O position, no battery packs will be connected to the charger port.

When the switch is in the I position, battery pack 1 will be connected to the charger port.

When the switch is in the II position, battery pack 2 will be connected to the charger port.

Aside from the charging aspect of the switch, will it control which battery is being run? Say I have a 36 volt 12 ah battery system tied to the 1 position and I have a 24 volt 7ah battery system tied to the 2 position: Position 1 would be adult mode on the 36 volt system Position 2 would be kid mode on the 24 volt system. Is this switch to be used separately from the on off switch that came stock (currie gt 350 scooter? If it replaces it then aren't you supposed to charge battery on scooter off position?
The Currie GT 350 electric scooter's charger port is connected to the battery pack before the power switch is integrated into the circuit. So the battery pack can be recharged if the power switch is on or off.

If the switch in the above wiring diagram is used to select which battery pack the scooter is running on, then it should be used separately from the main power switch, this way the power going to the controller can be turned off with the main power switch while one of the battery packs is being recharged.


Thank you very much. What is the difference in the two wiring diagrams in this topic? The first picture shows the battery pack negative terminals going to the dpdt switch pins. The second picture shows them commonly running to negative terminal of both packs. It also shows the positives being run to both pins. I am familiar with the wiring in the first picture. Could you shed some light?
The first wiring diagram was drawn specifically for using a SWT-154 to switch a battery charger port between two different battery packs.

The second wiring diagram was drawn to show how to wire two battery packs to a Currie, GT, Schwinn, or Mongoose electric scooter. The wiring harness depicted in the second wiring diagram could replace the scooter's existing battery pack wiring harness with no modification needing to be made to the main wiring harness. The SWT-154 switch in the second wiring diagram would select which battery pack was being used by the scooter and recharged by the charger.

The scooters main power switch would be left in place and used to turn the power on and off. However the power could also be turned on and off using the SWT-154 by selecting its middle position. When it was in its middle position neither of the battery packs could be charged though, so optimally the main power switch would be used to turn the scooter on and off, and the SWT-154 would be used in either its I or II position to select which battery pack is being used and recharged.

Login or Signup to post a comment