Click the picture to the left to see an enlarged image on how to wire up a 10S1P to 2 V-Balancers correctly. The only EXTRA piece of equipment needed is a double female to connect the charger side leads together.

Before Connecting - Ensure you have a voltmeter, two V-Balancers and your 12S1P pack ready for charging.

Confirm Final Negative / 0 Volts -
Fix the negative probe of the voltmeter to the negative output lead (main wire) of the battery pack, it will stay in place throughout these tests. We need to confirm the 0V connection of the pack. The pack itself has three balancing plugs, and this 0V position will more than likely be the only pin with a black wire but check this by using the positive probe of the voltmeter on the visible metal part on the back of the connector. Once found, this balancing plug will be connected to the first socket on the 12S harness lead.

Confirm Cell 1 +ve PIN -
Here we are using the voltmeter to confirm that the next pin is showing cell 1 +ve (expect a reading of between 3.0 and 4.2V, depending on charge state). This will again confirm that we are studying the first balancing connector.

Cell 5+ve Confirmation -
Here we are checking the final pin of the first balancing connector. This 6th wire will show us the voltage of cell 5 +ve. Expect to see a voltage reading between 15 and 21V. This connection is also shared with the first wire of the second connector as shown.
Now you should mark the connectors for future reference. We have found out which is the first balancing connector (with the 0V wire), which you should mark as connector number one. We have also found out which is the second connector (starting with cell 5+ve) which you should also mark.

Cell 10 +ve Confirmation -
Again, using our voltmeter, we need to confirm the positive of cell number 10. You should see a reading of between 30 and 42V. This will be the first wire of the third connector from the battery pack. You should mark this as the third connector.

Connection To The V-Balancers -
Now the balancers should be connected as illustrated below. You can see that the balancers need to be connected in series as shown. You must connect the positive of one balancer to the negative of the other on the charger side of the units. On the battery side, you must do the same. Study the photograph carefully; the first balancer has both the red leads connected to the other balancer, which in turn has both it's black leads connected.

Charging -
Now we can commence the charge. The main leads of the battery pack should be connected to the V-Balancers, and the main leads on the charger-side of the balancers should be connected to the charger. Now the charger should be set to a 12S Lipo charge, and a rate of 1C generally (for example, a 12S1P 3700 should be set to 3.7A charge rate). Once everything is connected, the charger will not commence until the V-Balancers are put into Link Mode (refer to the V-Balancer manual for detailed instructions) which can be accomplished by pushing and holding the button on both balancers at the same time. The Link ModeI LEDs will then come on and the charger will commence.

Finishing The Charge -
The charger will finish as usual when the battery pack is fully charged. At this time, if the V-Balancers are still in Link Mode, then you should push and hold both buttons again to switch off Link Mode. Once this is done, the battery pack can be disconnected from the balancers by it's main leads first, and the balancing leads in order 1, 2 and 3.
That's it! The pack is now charged and ready for use.