OK, you see the solenoids, or the winch motor as a possible reason for a voltage spike? What asbout the starter that we use to start our cars? It is practically the same setup as a winch. Now, if I were concerned sbout spikes, I would rather have 2 batteries in parralell to help absorb & buffer them.
The starter is isolated when you turn the key to start unlike the winch. Have you notice the electronics, gauges, radio ect., are off while starting the vehicle?
Batteries will not eliminate spikes.
I attend the IBEX convention every year. I attend the ABYC electrical, electronic & communications certification seminars each year. For the 9 years I have been attending, the use of multiple battery banks has been discouraged by the ABYC. I have only installed 1 2 bank system in a boat in all of this time:
(IBEX) International Boatbuilders Exhibition and Conference
(ABYC) American Boat & Yacht Council for you who don't know.
the use of multiple battery banks has been discouraged by the ABYC
<img src="/forums/images/graemlins/scared.gif" alt="" /> <img src="/forums/images/graemlins/confused.gif" alt="" /> You must have misunderstood.
Again: just for battery life, using 1 bank of 2 batteries gets 1/2 the depth of discharge & 1/2 the discharge cycles as compared to 2 banks of 1 batteries.
That leasd to longer battery life & allows the batteries to pull longer & deeper.
<img src="/forums/images/graemlins/confused.gif" alt="" /> You lost me.
Here is another way using a combiner You might want to do a search on combining batteries. Some good reading out there.
I would rather use a battery combiner than the relay mention in Kris's post, but they are a few bucks more. On the other hand, by using the relay, you have a quick way to jump start your vehicle without using jumper cables as would be the case using the combiner.
Here some food for thought, if you would like to run the engine while winching, I would suggest that you move the charging wire, from the alternator, to your second battery. Isolate the two batteries while winching using the switch I recommended. This will protect the electronics.
