Just sipping my first cup of joe, and still half asleep, but here's a few thoughts (I'll probably elaborate later if I remember)...
[EDIT: Woops! Should have finished that first cup of joe before starting to type. This SHOULD say "any standard double pole double throw contactor". Fixed. Also link fixed to the correct type of contactor.]
Use a transfer switch. It doesn't have to be a fancy one from Iota or someplace - any old 30a rated double pole double throw switch will do. You can even rig an "automatic" transfer switch using any standard 30a double pole double throw contactor with a 120v coil:
Cheap and easy to rig and then worry free after that.
An alternator/voltage regulator setup IS a trickle charger. Doesn't matter if you have a 190a alternator, or a 190,000a alternator; the voltage regulator will hold the "12v bus" voltage to a certain level, and however many amps the battery will allow to flow at that voltage is how many amps will go into the battery. Period. Depending on the resistance of the wiring and the battery, that'll generally be anywhere from 5a to 30a; and will taper off as the battery's voltage (and resistance) rises. Once the battery reaches a "surface charge" equal to the 12v bus voltage, there will be almost nothing flowing - even though the battery may only be at 80% charged.
There are special "battery charging" voltage regulators that will vary the output of the alternator to do a multi-stage battery charge. Without it, you've just got a trickle charger under the hood. Good enough to replenish a couple of amp*hours used to start the engine, not good at all for recharging a house bank.
A lot of times, people have problems with paralleled batteries, due to rigging it in such a way that the load/charge is not properly balanced through the battery bank. Here's a good page that explains how to do it right - and why:
(That's just a general comment - I have not actually looked at your diagrams yet. For all I know, you might be doing it right already.)
In general, in high voltage electrical wiring ("high voltage" in the electrical code sense - i.e., anything over 50v), neutral and ground are kept separate throughout the system, and only tied together at ONE point, and that's usually done in the main electrical panel and NOT done in sub-panels. If your rig is going to be plugged into a shore power system which already has neutral bonded to ground back at the main panel, then you DON'T bond neutral to ground in the sub-panel (or anywhere else) on your rig.
Also, a lot of inverters (and small generators) use what is called a "floating neutral" and when using one of those, you never tie the neutral to ground. Basically, with a floating neutral setup, there is no "hot and neutral" - what there is, is a pair of 60v hots which, when combined supply 120v. [EDIT: Sort of a smaller version of what happens when you combine a pair of 120v hots to get 240v in the panel at home.] You DON'T want to tie one of those hots to the frame or chassis or you risk creating a 60v potential which could lead to people getting bit.
For battery charging a house bank of flooded lead-acid batteries, the general rule of thumb for charger size is 5%-15% of the bank's total capacity. So if you've got a 400ah bank, then you'd need a charger sized between 20a-60a.
For charging off a generator, you would want to go to the bigger charger, to minimize generator run time (as long as the generator is large enough to handle the load of the bigger charger). Also, in terms of kilowatts per gallon of fuel, most generators are more efficient when loaded to at least 50% of their rated load.
You definitely DO want a good multi-stage charger. There is a problem with a lot of "3-stage" chargers, where they can get stuck in the absorb stage if there are loads running from the battery bank during charging. For that reason, you would want to use a charger which has a way of preventing that from happening and overcharging your batteries. An Iota charger with their IQ/4 control module added would be one of the best ways to charge a bank of flooded batteries. With the IQ/4 module, it will drop out of absorb after 8 hours regardless.
Without the IQ/4, the Iota is a "2-stage" charger, which has no absorb stage (only bulk and float stages). I would say for flooded batteries, you would want the IQ/4 mainly because it will bulk the bank up to 14.8v, which is perfect for flooded batteries. I agree with HandyBob about pumping up FLOODED batteries to 14.8v.
If you are sizing your charger up near the max of what the generator can handle - such as if you had a Honda eu2000i rated at 1600wC/2000wS, then keep in mind that most chargers don't have a very good power factor. Iotas for instance have a pf of .6. So if you'll be using a 1600w gen like the Honda, you should probably stick with a 45a or less charger. In general, the 1600w Honda *can* run a 55a charger...but it's marginal and if you go up in altitude, the power of generator's engine will drop off, and you might find that it runs the 55a charger just fine at the beach, but won't run it in the mountains.
That's enough for now...need another cup of joe.
Last edited by dwh; 06-13-2012 at 04:43 PM.
Current: 76 E-250, bubble-top, self-contained|couple of old Yamaha enduros
Previous wheelers: 41 Willys|78 FJ40|78 Bronco|84 Bronco|74 Ramcharger|78 Ramcharger|79 D150 PowerWagon|77 D100|79 D400 dually, converted to 4WD, utility bed, 10' Lance|75 Westy|69 Scout, RHD|bunch of others|bunch of bikes|couple of boats|couple of motorhomes|blah blah|so what|not my idea|just doin' what I'm told|wank wank|this space for rent|candy is dandy|but liquor is quicker