IOTA dls-90 vs. dls-90iq/4

That converter does not plug into a regular household outlet, it requires a 20 amp receptacle. That is AC, not DC.

Your alternator outputs DC.

Wire it to house batteries over solenoid and thick cabling for maximum current when batteries are depleted.

What batteries are you charging? how much capacity?

UNless they Are Odyssey group 31s, they do not require 40 amps per 100AH of capacity.

Charge rate for the battery capacity is a factor. Some batteries might not appreciate huge recharge currents when deeply discharged, Others will laugh at them.

If you are not plugging in then you do not need a converter. If you are plugged in a 30 amp is fine. This is totally separate from alternator charging.

To charge from the alternator you need to pull a big wire (#4) from the chassis battery to the house battery. Then you need a relay to connect when the van is running and charging.

Here is one example for a relay to connect the alternator:
http://www.powerstream.com/battery-isolator.htm

If there is something better someone will post it up.

Have you considered solar?

landyacht318 wrote:
That converter does not plug into a regular household outlet, it requires a 20 amp receptacle. That is AC, not DC.

Your alternator outputs DC.

Wire it to house batteries over solenoid and thick cabling for maximum current when batteries are depleted.

What batteries are you charging? how much capacity?

UNless they Are Odyssey group 31s, they do not require 40 amps per 100AH of capacity.

Charge rate for the battery capacity is a factor. Some batteries might not appreciate huge recharge currents when deeply discharged, Others will laugh at them.

The batteries I will be charging are two 12v vmaxtanks 155ah each, wired together.

Scott Malkinson wrote:

time2roll wrote:
Alternator should be connected direct to the battery through an isolator. Not through the IOTA converter.

Since you have the IOTA... what plug does it have? What are you planning to plug into?

I think you would be better with a 45 or 55 if you expect to plug into a common 15a supply (NEMA 5-15 common home outlet) periodically or use a regular extension cord or smallish 2000 watt generator. You would need to go down to 30 amp if you plan to use a 1000 watt generator. AGM does like to be charged fast so I would generally suggest going as large as your supply permits.

Consider some custom 12v cables here if using 90 amps:
http://www.genuinedealz.com/custom-cables?size=57

Or just the wire is priced well also.

Yeah, I forgot to mention that. I am going to be using a battery isolator and running the charger from that, since I am going to be doing a lot of driving. The IOTA I have has 120v plug, so im going to be returning it. This van is going to be used for expediting ( aka boondocking most of the time ) so shore power isn't going to be an opition. What type of charger do I need to run off of an isolator? How big of one can I use to be powered by an alternator?

DC to DC 50 amp charger
You will not need an isolator with this unit.

time2roll wrote:
If you are not plugging in then you do not need a converter. If you are plugged in a 30 amp is fine. This is totally separate from alternator charging.

To charge from the alternator you need to pull a big wire (#4) from the chassis battery to the house battery. Then you need a relay to connect when the van is running and charging.

Here is one example for a relay to connect the alternator:
http://www.powerstream.com/battery-isolator.htm

If there is something better someone will post it up.

Have you considered solar?

I want the power for the charger to come from the alternator, I don't want to charge directly from the alternator. As I understand it, its better for the batteries to go through a proper 3 stage charge. So I was thinking of using an isolator like the one in the link, then having the charger connected to the isolator. Would I use and inverter/charger for that? Im really starting to think about finding someone who does custom work and paying them to do this. My brother is pretty handy with this stuff, but hes never set up something quite like this.

Oh, and ive thought about solar, but im just trying to get rolling at the moment and keep it as simple as possible. That is proving to be difficult, lol. Plus im going to have a fantastic fan, rooftop a/c, and satellite on the roof.

If you want to double convert then you need a 1000 watt inverter attached to your chassis battery. This inverter can power your IOTA-30-IQ converter. This could very well be superior but that is about max I recommend from the system.

Chassis battery ---> 1000 watt inverter ---> IOTA-30 ---> House battery

No isolator needed but you will want to turn the inverter off when the van is not running.

IMO going to need to pull longish wire to keep the inverter inside away from the heat and elements of the engine compartment.

Inverter may prove useful to charge cellphone, laptop or watch tv. Just do not drain the chassis battery.

grizzzman wrote:

Scott Malkinson wrote:

time2roll wrote:
Alternator should be connected direct to the battery through an isolator. Not through the IOTA converter.

Since you have the IOTA... what plug does it have? What are you planning to plug into?

I think you would be better with a 45 or 55 if you expect to plug into a common 15a supply (NEMA 5-15 common home outlet) periodically or use a regular extension cord or smallish 2000 watt generator. You would need to go down to 30 amp if you plan to use a 1000 watt generator. AGM does like to be charged fast so I would generally suggest going as large as your supply permits.

Consider some custom 12v cables here if using 90 amps:
http://www.genuinedealz.com/custom-cables?size=57

Or just the wire is priced well also.

Yeah, I forgot to mention that. I am going to be using a battery isolator and running the charger from that, since I am going to be doing a lot of driving. The IOTA I have has 120v plug, so im going to be returning it. This van is going to be used for expediting ( aka boondocking most of the time ) so shore power isn't going to be an opition. What type of charger do I need to run off of an isolator? How big of one can I use to be powered by an alternator?

DC to DC 50 amp charger
You will not need an isolator with this unit.

Thanks grizz, I think this is exactly what im looking for.

I was very annoyed with the voltages my Vehicles voltage regulator chose.

With assistance from Mexwanderer, i bypassed my OEM voltage regulator and now control the vehicle's voltage with an adjustable voltage regulator whose adjustment dial is on my dashboard next to my digital voltmeters.Did someone just hear distant maniacal laughter?

That was Me.

The sterling product linked by grizzman is a dc to dc converter that takes whatever the vehicle's voltage regulator allows, and converts it to 14.x, then 13.x then a lower 13.x for the '3 stage' marketing mumbo jumbo with a 50 amp maximum.



I generally dial in 14.7v, 14.4v or 13.7v ( look three stages!) depending on where my battery state of charge is at, and the battery temperature. My alternator is rated at 120 amps. I've seen it deliver nearly that and my Northstar AGM battery has no issue handling that amount of current when depleted and the alternator is spinning fast enough and I have the voltage regulator cranked to 14.4v +.

No conversion losses. Total price, about 50$ in parts 25 for regulator, potentiometer, wiring and 10 ohm 50 watt resistor to trick engine computer.

Take power from alternator (+) stud rather than engine battery(+). OEM charging circuit is an electrical bottleneck, and taking power from engine battery just adds another circuit onto the end of that already too thin bottleneck.

But,

your Vmax tanks 155Ah batteries claim

MAX. CHARGING CURRENT: 35A MAX. CHARGING VOLTAGE: 14.7V RECOMMENDED: 15A, 14.5V

There are several dozen different ways and dozens of different products to get alternator juice to house batteries while saving engine battery from house loads with engine off.

You might soon be able to read about all the variable ways to do it in this thread.

I use a manual 1/2/both/Off switch. Blue seas 6007m. I am not keen on anything automatic concerning battery charging. My opinion and preference. Others feel the opposite, and might type louder.

Whatever method you choose, it takes about 3.5 hours for healthy batteries to get from 80% charged to 100% charged no matter how powerful the charging source might be.

Achieving 100% state of charge regularly is the key to battery longevity. The alternator told to make enough power to seek 14.4 volts can get the discharged battery to 80% relatively quickly, but that last 20% takes no less than 3.5 hours, even when held at absorption voltage and with a 50 ampDC to DC converter, or a 120 amp alternator providing the current, whenever the engine is running.

Solar is pretty good at holding 14.4v for those several hours after alternator has gotten them to 80% relatively quickly.

Alternator + sufficient solar could yield good to excellent battery life. The alternator alone rarely can do more than 'poor' to 'fair' battery life when the batteries are cycled deeply, daily.

Being able to plug in for days to give the batteries a chance to reach 100% and also give them a rest from cycling is a big help too.

How long they last and if this time is acceptable to owner is subjective and highly variable depending on depth of discharge and how close to fully charged they get. Only getting to 95% each recharge is not good enough. Even 99% is not day in and day out. That last 1% can take an hour and can double battery lifespan in a daily deep cycle application. The last 1% is especially important with an AGM battery.

40A In-Vehicle DC Battery Charger
https://www.redarc.com.au/in-vehicle-battery-charger-40a

Those Redarc chargers look like good units.

These battery-to-battery chargers from the marine world look good too:

http://sterling-power.com/collections/battery-to-battery-chargers