High Output Alternator with CTEK D250s and Smartpass

[aschafer14]

I am trying to plan out the proper battery and charging system for my rig and have a few questions. I have been reading up all I can but cant seem to find an answer. I reached out to CTEK directly but I haven't received a response. Any help would be greatly appreciated.

Here is my plan as it stands right now:

Already Installed
Alternator: 1 Wire(self exciting) – 200 Amp peak, 100 Amp at Idle

Battery Management
CTEK 100A Off Road
• 250S Dual
• Smartpass
• Battery Monitor

Inverter
2000W Pure Sine Inverter (TBD)

Batteries
Starting Battery - DEKA Intimidator Group 31 AGM
House Batteries – 2 6V Lifeline GPL-6CT 300AH Deep Cycle AGM

Solar
(2)-80-100 watt panels, possibly more in the future.

1. My main question is about my high output one wire(self-exciting) alternator? Will there be any issues using this with the CTEK controller or does the unit just regulate the amperage down to the maximum output of the controller.
2. Is the solar capacity still limited to the 20A of the D250S or is it increased due to the Smartpass. If it is limited to 20A am I correct in assuming I could run a 12v system with up to 240watts of solar before I was maxing out the amperage?
3. What will I need if I want a shore power connection, will I need to upgrade to an inverter/charger instead of just an inverter?

Again any insight you can give me would be a huge help, let me know if I left out any key details

 

[DiploStrat]

1. My main question is about my high output one wire(self-exciting) alternator? Will there be any issues using this with the CTEK controller or does the unit just regulate the amperage down to the maximum output of the controller.

Irrelevant. Your CTEK does not "see" the alternator. It merely creates a drain on the starter battery. When the SmartPass is closed, that drain can be up to 80A and when the SmartPass is open, then the drain is limited to about 20A, the capacity of the D250S. This current is used to charge the camper battery. The alternator merely notes that the starter battery is discharging and responds by producing current, up to its limits. There is no connection between the CTEK components and the alternator.

2. Is the solar capacity still limited to the 20A of the D250S or is it increased due to the Smartpass. If it is limited to 20A am I correct in assuming I could run a 12v system with up to 240watts of solar before I was maxing out the amperage?

The D250S has a maximum charge capacity of 20A; it makes no difference if it draws from the solar panel or the starter battery. The SmartPass is an intelligent, voltage sensing relay that allows a direct connection between the starter battery and the camper battery. (It is rated to handle a maximum of 80A.) It has no impact on the solar charger in the D250S.

Basically, when the voltage conditions are met, the SmartPass closes a relay and allows the starter battery/alternator to charge your camper battery directly, thus providing more amps during the bulk charge stage. There is, however, no voltage boost. Once the amp flow drops to 20A, the SmartPass opens and the D250S completes the absorb stage with voltage boost.

3. What will I need if I want a shore power connection, will I need to upgrade to an inverter/charger instead of just an inverter?

For shore power you will need either a charger or an inverter/charger. A pure inverter does not charge your batteries, it only takes 12v DC from your battery and produces 110v 60Hz AC current. (Or 220v 50Hz if you are in Europe.)

The information you need is here: http://smartercharger.com/wp-content/uploads/2010/11/D250S-DUAL_EN.pdf

See especially page 20.

Hope this is helpful.

EDITED TO ADD THE OBLIGATORY REMINDER: Do measure the voltage of your charging system BEFORE you spend money on a B2B. If your vehicle is already running at over 14v (at 20C/70F), then there is no reason to pay extra for a B2B to boost the voltage. Simply use a key controlled or intelligent relay and wiring of the appropriate size.

 

[aschafer14]

Thanks I think I'm starting to get it now. I read through some of the documents you wrote up on your site as well as a few other posts too and they were very helpful. The engine is out of the truck at the moment but I contacted the alternator manufacturer and they said it would supply 12.8-14.6 volts, it was made for a Dodge Truck up to 2002 so I am assuming it will be fine without the B2B charger and I can just go the intelligent relay route. Once I get everything fired up I'll check the voltage output.

It seems I was probably overthinking things. If I understand correctly, the alternator will top off the starter battery rather quickly and then be focused on bulk charging the house batteries, it would take long drive times to see the benefit of a multi stage charger like an A2B charger. Using solar to top off the house batteries is much more efficient since the amperage required decreases as the batteries become charged.

So it looks like the BlueSea ACR (7622) is a pretty popular option. The only question I have is since I wont be using the same batteries for starting and charging is there any danger to shortening battery life. If I understand correctly, it is dual sensing so the batteries will be connected when it senses a charge from either the alternator or the solar cells which will be a good portion of the day.

 

[GoodEnoughforGabe]

Irrelevant. Your CTEK does not "see" the alternator. It merely creates a drain on the starter battery. When the SmartPass is closed, that drain can be up to 80A and when the SmartPass is open, then the drain is limited to about 20A, the capacity of the D250S. This current is used to charge the camper battery. The alternator merely notes that the starter battery is discharging and responds by producing current, up to its limits. There is no connection between the CTEK components and the alternator.


I would recommend a Blue Sea Systems ACR (Automatic Charging Relay) to be able to handle the load of your alternator. They've been making boat electrical systems for a long *** time. I found mine online for like 175 bucks.
https://www.bluesea.com/products/76...rging_Relay_with_Manual_Control_-_12V_DC_500A

There are delays on joining and separating the batteries, so the load is not shared when starting, even when in auto mode.

 

[DiploStrat]

Thanks I think I'm starting to get it now. I read through some of the documents you wrote up on your site as well as a few other posts too and they were very helpful. The engine is out of the truck at the moment but I contacted the alternator manufacturer and they said it would supply 12.8-14.6 volts, it was made for a Dodge Truck up to 2002 so I am assuming it will be fine without the B2B charger and I can just go the intelligent relay route. Once I get everything fired up I'll check the voltage output.

It seems I was probably overthinking things. If I understand correctly, the alternator will top off the starter battery rather quickly and then be focused on bulk charging the house batteries, it would take long drive times to see the benefit of a multi stage charger like an A2B charger. Using solar to top off the house batteries is much more efficient since the amperage required decreases as the batteries become charged.

So it looks like the BlueSea ACR (7622) is a pretty popular option. The only question I have is since I wont be using the same batteries for starting and charging is there any danger to shortening battery life. If I understand correctly, it is dual sensing so the batteries will be connected when it senses a charge from either the alternator or the solar cells which will be a good portion of the day.

I'm glad the material is helpful. Remember, all of this is for lead acid batteries only, lithiums are another question.

"Multi-stage" is somewhat true and somewhat merely marketing. Depending on your vehicle, it probably has very close to a multi-stage charger, depending on how the manufacturer wrote the software in the engine and body control computers. My 2013 Chevrolet is especially sophisticated, even including an equalization cycle.

In the end, at their simplest, your vehicle's charging system will attempt to maintain a constant voltage typically 13.9v from the internal regulator, often overridden to a higher voltage by the computer or other controller. Once that voltage exceeds 14v at 20c/70F you are in good shape. The "multi-staging" is largely a factor of the natural rising voltage curve of a lead acid battery - as the voltage rises, the battery takes ever less current, thus the absorb/accept stage. So while not taking anything away from the cleverness of the charger manufacturer, you are going to get a bulk and absorb stage no matter what you do.

I agree 10,000% with your comment about solar - solar is fantastic for assuring that you get the last bit of that long absorb stage. The D250S does a bit the same thing, but as you noted, many folks never drive long enough to make it an issue.

Final note, should you find that your voltage is still too low when you put in your new alternator, Mechman (http://www.mechman.com/voltage-control-modules/) makes various devices that allow you to trim the voltage. I know at least one Toyota owner who does this so that he can run a voltage sensing relay and still reach the voltages his batteries want.

The D250S/SmartPass combo excels when you want to add a small solar array and don't want a separate solar controller.

Good luck!

 

[aschafer14]

Ok great, thanks for the clarification on all that stuff. We're a bit off topic now but here is my first(well I guess second now) stab at my starting and charging system. I'm still doing some research on proper wire/fuse sizes but the main building blocks are there. Let me know what you guys think.

 

[DiploStrat]

Looks good!

Wire gauge is not that hard, use this: http://www.calculator.net/voltage-d...nce=15&distanceunit=feet&amperes=100&x=38&y=6

You can plug and play to your heart's content.

FWIW, I have had good performance with our Magnum Energy inverter/charger. (And replaced an off brand unit.)

Look at Blue Sky solar controllers, their IPN Pro remote incorporates an hour counting battery meter and it tracks well with my TriMetric. In the end, what the meter shows you is interesting, what it shows the controller is essential.

Finally, rule of thumb, 5A charge per 100w of solar. One or two of these are very cost effective and even have a bit of US content: https://www.amazon.com/Grape-Solar-...sr=8-1-spons&keywords=grape+solar+panel&psc=1

Good luck!

 

[aschafer14]

Thanks for that calculator that should help a lot.

Those Magnum Energy units are pretty steep. The 1000W Renogy unit is Pure Sine with 30A charger and 20A pass through, the comparable Magnum unit of similar stats is 2.5x the price, it does have 50A charger but I don't really see a need for it since I would normally be charging overnight. The Renogy unit looks like it may be just a re-branded AIMS unit.

Can you explain how your Blue Sky remote provides feedback to the TriMetric? Is it mainly a temperature sensor feedback? The reason I'm leaning towards the Victron MPPT is it allows fully programmable charge profiles and can be connected to an optional bluetooth connector so I can monitor things from my phone or PC with 30 days of logging. It doesn't have a battery temp input but does have a temp sensor on the unit so if placed in close proximity to the batteries I'm hoping that will be good enough. There is an input for battery temp on the monitor but it won't feedback into the controller.

The 30A controller allows up to 440w of solar input, I will start out with around 200W and probably quickly upgrade to 400W. Those grape solar panels look like a pretty sweet deal, I just need to see if the compact nature of the Renogy Eclipse units(1.86 watt/sq-in) vs 1.36) is worth the extra price (21 cents/watt vs 16 cents))

 

[DiploStrat]

Clarifications

The advantage of certain Magnum inverter/chargers is that they are low frequency models with big iron laminations and good overload capacity. Most others are high frequency models - great for charging your computer but possibly less able to handle a microwave or air conditioner.

Sorry, I was not clear. What I mean is that, after two years of real world use, the TriMetric and the Blue Sky meters give the same readings. I would not bother with the TriMetric again, but simply use the Blue Sky; you don't need both.

Again, you don't need a hyper accurate battery SOC meter - what you need is a properly programmed solar charger.