2nd Alternator

[John61CT]

The Hellroaring units are (at least functionally) more like VSR/ACR "combiners", split charge relays, lots of variations in implementation and terminology, but basically these all automatically dis/connect the start/house circuits based on voltage and when closed allow current to flow in both/either directions.

"Isolators" are usually simpler, just restrict current to only flow one way. The Xantrex Echo Charger is automatic, but also one way and does limit current flow and voltage, I think pretty much category of one.

And low voltage disconnects, protect a bank from being drawn down by cutting non-essential loads, similar concept but different approach.

Then you have DC-DC chargers, best used when banks need different voltages, or if you want to keep a bank charged up even with no charge source active.

Solenoids are fine if you want the connection based on a simple on/off switch condition, usually from ignition if running the engine/alt is the only charge source. The fact that their parasitic draw is pretty high doesn't matter much in that scenario, and low cost is always a plus.

More complex requirements do cost more; I'm not plugging expensive solutions per se, just pointing out, if someone wants the functionality of the old-school diode-based isolators for their particular use case, that there are modern implementations without their traditional disadvantages.

 

[SternWake]

Those FET based isolators Look to be good. MOre than I'd want to spend, but if I were given one I'd certainly employ it.

BUt I'd rather have a silver tungesten contact Solenoid rated for 200 amps for 55$, and make sure it was not assisting engine battery when starting motor.

There are so many many ways to complete the objective of charging house batteries with engine on and not discharging engine battery with house loads engine off.

 

[DannyB1954]

A higher output alternator may be available for your vehicle. This would be a much simpler solution than 2 alternators. The wires to the house battery should be attached to the alternator as the original wiring harness would not be sized for the higher output alternator.

 

[SternWake]

Looks like there are two alternators for that v6
110 amps and 130 amps

http://www.rockauto.com/en/catalog/...305937,electrical,alternator+/+generator,2412

Not much difference and likely not worth the expense of upgrading for 20 more MAX amps. but who knows if conditions will be met where it can realize those 20 more amps. They might be very similar at 2000 engine rpm, but at 2500 rpm the 130 produces more. A couple lower rated balmar alternators beat their higher rated brethern at lower rpms.

Now could more powerful alternator not listed by rockauto as a drop in replacement be fitted to the engine? I bet so. I guess there are serpentine belt Width considerations when one gets up over 150 amps.

I Wonder if one could mount a large frame underbody alternator, spun by A large pulley on the driveshaft.

I'd get more solar if possible. Agms like higher rates of recharge, and low and slow solar only recharges, when deeply discharged regularly, equals unhappy AGMS. The Occassional higher amp recharge from their most depleted state, should be considered a goal, every so often.

I regularly intentionally draw my down further to 30% or so, just so it has more time to accept 40+ amps and wake back up after many partial state of charge cycles or a bunch of low and slow solar only recharges.

And I have more than 2 Solar watts to 1 AH capacity and would LOVE to have 3 to 1.

 

[Nissi]

Actually, there is another more advanced isolator which uses field effect transistors instead of diodes. No voltage drop. I've used one my Peterbilt motorhome conversion for the past seven years with zero problems. Google Jamestown Distributors for more information. More expensive than a solenoid but completely "automatic" and trouble free.

I am going to assume you are referring to the Victron Argo...   ?

:shy:

 

[Nissi]

I want to thank everyone for their GREAT input !!  Appreciate everyone as
so many uses and thoughts in setting up our RV's to work the best way
for each of us!

I think this is a subject that could easily be written up in depth for this forum! 

This is most probably one of the best forums on the www!!!  
I love reading and listening to y'all.  :shy: :shy:

 

[speedhighway46]

I am going to assume you are referring to the Victron Argo...   ?

:shy:

yes, that is correct.

 

[Trebor English]

Solenoid switches use some power to keep the contacts closed but the current passed through goes pretty much unimpeded. Other technologies have heat sinks to dissipate the heat generated by resistance to the current being passed.