How small of a battery with a Leece-Neville 555 160 amps

[XYZER]

I am putting togeather a Kubota 12 hp with a 4000 watt gen head and will introduce a Leece-Neville 555 into the mix. The unit will have a small starter battery to start the Kubota. Will the Leece-Neville 555 regulate correctly with a small battery and not be a big concern?

[Ronmar]

Is this a standby application or a daily driver? Long hours or short runs?  It should regulate fine, but for a long term running application, I think the typical 14.5V that an auto alternator outputs is a little high for a long term runner.  The 555 is way overkill for just charging a small starting battery, so I am guessing it is for some more serious DC power generation plan? If so, that might not jive well with charging a bank or whatever and charging the starting battery.  I am kind of in the same situation, and am going to remove the alternator from my china diesel genset and just use a small plug-in float charger.  When not running, i can plug it in and keep the battery floated.  When running, i can plug it into the genset output to return the power consumed while starting.

[mbryner]

I'm going to use a small trickle charger for the starting battery.   It's plugged into the regular off-grid inverters of the house.   I'm also thinking since I do long engine run-times for charging the large battery bank, maybe I'll just plug in the trickle charger into the output of the ST head.    One less ghost load for the inverters.    

Then, to take it one step further than Ronmar,  if you need some DC out that is more than the trickle charger can keep up with but you don't need a large alternator spinning constantly,  I have another idea:  hotwire a cheap ATX computer power supply.    Normally they won't turn on unless plugged into a motherboard, but if you jumper the green on-off sense wire to the black ground wires (on the 20 pin motherboard cable) you have a very cheap but short-circuit-protected and relatively powerful 12 V DC supply.   Don't know how efficient this would be, but I'm going to try it maybe later tonight after work.   Can't be more inefficient than a constantly spinning alternator. (?)

Marcus

[XYZER]

Well I had all the pieces and will eventualy use it at my offgrid camp. I need 220 volts to run my well pump and in the winter also I can use use the 12 volts to charge my 4 6volt deepcycle batteries that are taken care of in the summer with a solor panel. In the mean time I was going to put a small 12volt on it to start the kubota and keep the alternator out of trouble also making it portable battery charger/generator. This is not an assembly of choice but of extra pieces. The Kubota would handle much more.

[Lloyd]

Xyzer,

It will work, but I wouldn't use the stock built in regulator, but go with an external Balmar controller. That way you get a proper charge regime to the big bank, then you can add a Balmar Digital Duo Charge to the start bank. DDC does not care where the charge current comes from; the alternator, or solar panels, what ever charge source is going to the house bank will then give the start bank a proper charge.

When there is no charge demand on the alternator it will just be spinning taking a little more then an Idler pulley...maybe 1/16 HP or less.

Lloyd