Wiring Two Victron Orion XS DC/DC Chargers

[Happy29]

MB has calculated the max allowed additional load based on a worst case scenario of OEM equipment loads all being enabled at the same time.

I would expect heated seats both on max would demand 20A if not more, and a 2nd AC unit drawing even more, though unlikely one would use both at the same time but MB has to expect someone would. There's also that damn electrical heater that cannot be user disabled that must suck up a ton of A, albeit for a rather short amount of time before the coolant heat exchanger takes over.

I feel the 80A extra is conservative, if not very conservative, if one doesn't have or use these extra OEM loads.

Food for thought.

 

[Kajtek1]

When I was restarting my NCV3 in the morning, to make my morning coffee, I estimate that my house was drawing 130 amp at idle just fine.
The system kept 14V with small house battery depleted.

 

[Diver160651]

MB has calculated the max allowed additional load based on a worst case scenario of OEM equipment loads all being enabled at the same time.

I would expect heated seats both on max would demand 20A if not more, and a 2nd AC unit drawing even more, though unlikely one would use both at the same time but MB has to expect someone would.

I feel the 80A extra is conservative, if not very conservative, if one doesn't have or use these extra OEM loads.

Food for thought.

Ya, I don't have anything that draws much unless I was winching or using the Slide out - I probably could disable the DC chargers in that event.

So I guess the question is do I leave one a 50amp or even 40amp and the activate the other only at highway speeds for a total of 80amps in the rare case..

From what I understand the original stock 2, 100 AGMs could easily pull 50 amps each when charging.. Seems to me that I would be charging a low rate with only 1 dc/dc charger enabled and for that matter even if I set them to only deliver 80 max when combined.. I know they are only rated at 98% efficiency but that seems like not that much additional draw.

What am I missing?

 

[Happy29]

Ya, I don't have anything that draws much unless I was winching or using the Slide out - I probably could disable the DC chargers in that event.

So I guess the question is do I leave one a 50amp or even 40amp and the activate the other only at highway speeds for a total of 80amps in the rare case..

From what I understand the original stock 2, 100 AGMs could easily pull 50 amps each when charging.. Seems to me that I would be charging a low rate with only 1 dc/dc charger enabled and for that matter even if I set them to only deliver 80 max when combined.. I know they are only rated at 98% efficiency but that seems like not that much additional draw.

What am I missing?

98.5% is wildly efficient for what they are doing. As I said, I like to split the load between the chargers. Why work either to it's max if not required. It only takes moments to change the values on phone as needed.

 

[Diver160651]

98.5% is wildly efficient for what they are doing. As I said, I like to split the load between the chargers. Why work either to it's max if not required. It only takes moments to change the values on phone as needed.

Ok that makes sense - I guess from a heatsink perspective as well distributed across both

 

[Happy29]

Ok that makes sense - I guess from a heatsink perspective as well distributed across both

Yep, and the losses from the cabling and connectors. Less current, less lost as heat.

 

[Diver160651]

You guys need a second dedicated charging alternator or upgrade your stock alternator. Pulling 100A off the stock alternator that is already undersized is asking a lot of the factory system. If you want to have both only run 1 charger at a time.

I install 2 XS chargers for my customers that use their vans for winter camping. The second is a backup in case the first fails, but this is only for emergency situations in cold temperatures.

FYI I already have a big van converted heavier subframe/solid axels/heavier suspension, that all contributes to being near max GVWR for a 3500 when fully loaded Even with an aux oil cooler and bypass that acts like a couple of degree heatsink, engine heat/load is a concern for me.

In my case, I really would not want to add an high output 280amp second alternator. I don't really know how much additional load these place on an already tax'd engine; but from running my onboard welder on my past crawlers when the welder kicked in, it would actually load the big V8 and drop several hundred RPM even when I had the idle up high.. So I imagine when off-roading or up big hot grades here in the West, the extra load might not be ideal.

So I am trying to do this in a reasonable way especially sense I don't really require much DC power most of the time.. But as you mentioned, my concern is winter and having much shorter charge windows.

 

[StogieMan]

MB has calculated the max allowed additional load based on a worst case scenario of OEM equipment loads all being enabled at the same time.

I would expect heated seats both on max would demand 20A if not more, and a 2nd AC unit drawing even more, though unlikely one would use both at the same time but MB has to expect someone would. There's also that damn electrical heater that cannot be user disabled that must suck up a ton of A, albeit for a rather short amount of time before the coolant heat exchanger takes over.

I feel the 80A extra is conservative, if not very conservative, if one doesn't have or use these extra OEM loads.

Food for thought.

I agree with you and feel that the 80A figure is conservative. I too have been running two Orion XS’ for two years charging at 50A's each before I took them off last month as I got a second 48v alternator installed. I’ve never had any issues other than the chargers getting a bit too warm. Prior to that I had two original Victron 50A Buck Boosts. (Lacked the tech & communication but better built IMO) I ended up adding a second shunt to be able to view the alternator information on the Cerbo GX.

Both the Orions XS and the original Buck Boost will ran hot. I ended up adding a few fans with a temp controlled thermostat and installed a Victron Battery Smart Battery Sense on each one so that I could monitor the temps while driving. I’ve seen them getting close to 130 degrees. Two of those in a tight area for sure will create some heat so you need to plan for some fans or ventilation.


First setup:



Replacement Setup:



Most recent setup that is all apart now awaiting the 48v system

 

[Happy29]

I've not had any overheating issues. I don't think 130F is outside of their normal range and likely didn't derate 130F would derate ~30%. I have more space than you though and setup a slow fan to move air across both of them whenever they are enabled.

Per Victron XS12/12-50:

Operating temperature range

-20 to +60 °C (140F) (derating 1.5% per °C above 40 °C)​

 

[blutow]

You guys need a second dedicated charging alternator or upgrade your stock alternator. Pulling 100A off the stock alternator that is already undersized is asking a lot of the factory system. If you want to have both only run 1 charger at a time.

I install 2 XS chargers for my customers that use their vans for winter camping. The second is a backup in case the first fails, but this is only for emergency situations in cold temperatures.

Adding a 2nd alternator is a pretty big trade off in complexity and cost. I'm not saying it's not a good path if you really need the charging amps, but I see quite a few reports of people having issues with their secondary alternators (not just the alternator, but issues with belts jumping, bracket alignment, damaged threads where it mounts to engine/pan, etc.). I'm sure they work fine in many cases, but I'd be surprised if their failure rates weren't dramatically higher than just pulling some amps from the primary stock alternator through a DCDC charger.

And I'm not sure I'd consider the stock alternator undersize. My van has the 250a alternator and I think the "small" standard alternator is 220a. The 80a MB limit is going to be based on worst case on vans with a lot of accessories. I wouldn't design a system that exceeds the 80a limit on a regular basis, but I wouldn't hesitate to pull 100a during highway driving on a long trip if I needed more charging. The earlier post about configuring the system to throttle up and down based on travel speed would be ideal. Pulling 100a at highway speeds is likely much easier on the alternator than pulling 80a idling in traffic on a hot day.

 

[jdubbayew]

Adding a 2nd alternator is a pretty big trade off in complexity and cost. I'm not saying it's not a good path if you really need the charging amps, but I see quite a few reports of people having issues with their secondary alternators (not just the alternator, but issues with belts jumping, bracket alignment, damaged threads where it mounts to engine/pan, etc.). I'm sure they work fine in many cases, but I'd be surprised if their failure rates weren't dramatically higher than just pulling some amps from the primary stock alternator through a DCDC charger.

And I'm not sure I'd consider the stock alternator undersize. My van has the 250a alternator and I think the "small" standard alternator is 220a. The 80a MB limit is going to be based on worst case on vans with a lot of accessories. I wouldn't design a system that exceeds the 80a limit on a regular basis, but I wouldn't hesitate to pull 100a during highway driving on a long trip if I needed more charging. The earlier post about configuring the system to throttle up and down based on travel speed would be ideal. Pulling 100a at highway speeds is likely much easier on the alternator than pulling 80a idling in traffic on a hot day.

Respect all the opinions here, to each their own. I've a few dozen systems from scratch. These vans CAN systems are incredibly sensitive to under-voltage voltage.

 

[Motormad]

For configuration:

• Run one DC/DC charger set to delay start at 50 amps, while the second is manually disconnected through the app. but maybe set to 30 amps
• Run one DC/DC charger with a delayed start at lower amps, like 30 amps, while keeping the second fully capable at 50 amps but manually disconnected.
• Run both chargers at lower amps and increase them when needed.

Personally I would (and have) configure both on, running at a lower output, and ramp them up if needed.

I also share the view that the 80A max recommended is conservative, but as mentioned above, I do not ramp mine up to 100A until the van is at motorway (freeway) speed when the revs are up and it will also have taken a while to get there so effectively delayed to enable the starting power draw to have been replenished. If drawing heavily with van requirements (high fan, headlights, etc.) I can and will reduce the load to the LBs.

A development in progress (once it gets a bit warmer) will be current monitoring into the van battery to ensure an even more sympathetic approach for the alternator

 

[SpooledReel]

Adding a 2nd alternator is a pretty big trade off in complexity and cost. I'm not saying it's not a good path if you really need the charging amps, but I see quite a few reports of people having issues with their secondary alternators (not just the alternator, but issues with belts jumping, bracket alignment, damaged threads where it mounts to engine/pan, etc.). I'm sure they work fine in many cases, but I'd be surprised if their failure rates weren't dramatically higher than just pulling some amps from the primary stock alternator through a DCDC charger.

And I'm not sure I'd consider the stock alternator undersize. My van has the 250a alternator and I think the "small" standard alternator is 220a. The 80a MB limit is going to be based on worst case on vans with a lot of accessories. I wouldn't design a system that exceeds the 80a limit on a regular basis, but I wouldn't hesitate to pull 100a during highway driving on a long trip if I needed more charging. The earlier post about configuring the system to throttle up and down based on travel speed would be ideal. Pulling 100a at highway speeds is likely much easier on the alternator than pulling 80a idling in traffic on a hot day.

This right here sums up my exact thoughts when i set up dual xs50's, i ran them like this for our 4 thousand mile trip last year

 

[Motormad]

I will re-iterate, for those that have a GX device with their Orion's (Cerbo GX or similar) it is relatively easy to programme some logic in NodeRed to control the charge profile of the Orions. I am happy to help if this is something someone wants.

 

[SpooledReel]

I will re-iterate, for those that have a GX device with their Orion's (Cerbo GX or similar) it is relatively easy to programme some logic in NodeRed to control the charge profile of the Orions. I am happy to help if this is something someone wants.

I am interested. I know absolutely nothing about node red. Is there a preset code that you write in through VRM?

 

[Motormad]

I am interested. I know absolutely nothing about node red. Is there a preset code that you write in through VRM?

I would not wish to do anything remote into your system. However, if you have an idea of how you would like to trigger the change in charge profile, I can suggest some code for you to enter. NodeRed is broadly a visual programming tool (even I can do it )
When I mention trigger the change, it could be a delay, a switch (or some other digital input in the Cerbo), a SOC value, or something else that the Cerbo is monitoring??

 

[SpooledReel]

I would not wish to do anything remote into your system. However, if you have an idea of how you would like to trigger the change in charge profile, I can suggest some code for you to enter. NodeRed is broadly a visual programming tool (even I can do it )
When I mention trigger the change, it could be a delay, a switch (or some other digital input in the Cerbo), a SOC value, or something else that the Cerbo is monitoring??

Thank you, Appreciate the follow up. Let me look into some of the node red videos and see what’s up. Maybe I can message you directly for some of this code stuff?

 

[Motormad]

Thinking about triggers, what connection do you have from the van to the Victron kit?
Do you have:

• An ignition or D+ signal going to the Cerbo (best)
• Monitoring the van battery voltage with BMV or similar
• GPS sensor for Cerbo

How are the Orions triggered - just using the Smart detection?

 

[SpooledReel]

I wish I had thought to run the D+ signal upfront. I just have the smart detection on each XS. I have tinkered a bit with the settings and probably need to adjust more as my starter voltage is staying at 13.3 after recently wiring in a “House 2 Start”

here’s a screen shout of the current battery parameters in the XS

 

[SpooledReel]