# Wiring Parallel and Series Simultaneously

Is it possible to connect 3 sealed lead acid batteries in both parallel and series at the same time like in the diagram below?

• Note that your 12v and 36v wires are shorted together. Obviously, this cannot work. Commented Nov 14, 2016 at 0:09
• @Optionparty the answer editor on this website does have a schematic editor Commented Nov 14, 2016 at 0:43
• Click on the schematic editor button above the answer field. Commented Nov 14, 2016 at 0:56
• @MarcusMüller Thank you so very much. I think I will be able to contribute more often. Commented Nov 14, 2016 at 2:36
• Yes it is possible. However, you might not like the results. Commented Jan 11, 2019 at 4:31

## 3 Answers

A 4P2T could switch the 3 batteries from (series 36v) to (parallel 12v).

simulate this circuit – Schematic created using CircuitLab

• thank you so much! out of curiosity, is it possible to use dip-switch instead of 4P2T switch? Commented Nov 14, 2016 at 12:46
• @harayz the thing about the 4P2T switch is that they switch simultaneously, so that there's no chance you accidentally short something. And no, dip switches are for milliamperes, so you certainly won't charge batteries through them. Commented Nov 14, 2016 at 13:08
• A diode in series with a 12v charger, in parallel with the output, would provide automatic charging when the 4P2T is in the 12v position and become a blocking diode when the 4P2T is in the 36v position. Commented Nov 14, 2016 at 14:03

NO. If you look closely at your diagram, you will see that your green links form a DEAD SHORT from GND to 12V. Clearly not viable at all. Don't even think about it.

To achieve this you would to wire all the connections back to a couple of relays and just switch between them as needed. You'd need to be careful to prevent energising both relays simultaneously, achieving a dead short as pointed out in a previous answer. To do this you could wire the signal to Coil 1 through a NC (Normally Closed) contact on the opposing relay. When you energise Coil 2, the NC contact will open, preventing current travelling to Coil 1.