17' Series Power requirement

Timmac

New Member
Jun 26, 2022
5
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3
Phillip island Victoria
Evening all. Hoping for some quick advice.
just purchased a outback 17.56 2
Have optioned a non gas fridge, never been a fan of gas fridges.
just curious if anyone is using one. Have optioned 2 x 120 ah lithium batteries. Have the standard 150 watt panel on the roof and have a good portable 300 w to help charge. Hoping it should be enough to run off grid for a week or two.
cheers. Any advise be great.
 

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
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Ferny Grove, Queensland
Evening all. Hoping for some quick advice.
just purchased a outback 17.56 2
Have optioned a non gas fridge, never been a fan of gas fridges.
just curious if anyone is using one. Have optioned 2 x 120 ah lithium batteries. Have the standard 150 watt panel on the roof and have a good portable 300 w to help charge. Hoping it should be enough to run off grid for a week or two.
cheers. Any advise be great.
@Timmac , the standard PWM solar controller will not be the best for Lithium battery charging nor will the normal 240 volt charger in your van. The charging algorithm is different. Both solar panels will have to be Lithium compatible - suggest good MPPT types _ as they have user adjustable settings. Have a look at the difference in charging requirements for Lithium and Lead Acid type AGMs and GELs. It would be a shame to ruin/shorten the life of your very expensive Lithiums with incorrect charging. To avoid having two MPPT controllers, it is better to bypass the one on the back of portable and connect output terminals to the same Pos and Neg terminals of your internal MPPT controller, that way the 150 watt rooftop panel and the portable 300 watt work through the one controller. Suggest at least a 30 amp or 40 amp controller. Also, do you have a Lithium suitable 240 volt charger at home. Will be necessary, as van charger not really suitable unless Lithium compatible.
 

Boots in Action

Well-Known Member
Mar 13, 2017
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Ferny Grove, Queensland
@Timmac , the standard PWM solar controller will not be the best for Lithium battery charging nor will the normal 240 volt charger in your van. The charging algorithm is different. Both solar panels will have to be Lithium compatible - suggest good MPPT types _ as they have user adjustable settings. Have a look at the difference in charging requirements for Lithium and Lead Acid type AGMs and GELs. It would be a shame to ruin/shorten the life of your very expensive Lithiums with incorrect charging. To avoid having two MPPT controllers, it is better to bypass the one on the back of portable and connect output terminals to the same Pos and Neg terminals of your internal MPPT controller, that way the 150 watt rooftop panel and the portable 300 watt work through the one controller. Suggest at least a 30 amp or 40 amp controller. Also, do you have a Lithium suitable 240 volt charger at home. Will be necessary, as van charger not really suitable unless Lithium compatible.
Hi again @Timmac , found this link which explains why using a standard lead acid charger or non suitable solar controller will not be good for your Lithium batteries. Hope this is helpful.

 
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Drover

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Nov 7, 2013
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QLD
Thanks boots. Assuming as it’s a new van built with lithium it should have the j35 d which I’m lead to believe should run lithium fine and should include a lithium compatible 240 volt charge.

Thats right so you should be covered in that respect though I would be upping the solar if going a compressor fridge, have had too many friends mention they are happy at 400w to keep things going and not drag the guts out of their batteries and thats including a portable.......... Of course it all depends on what your daily draw is and fridge size has a bearing on it, having plenty of panels means batteries are charged early and quickly during the day, the panels to be running the van including the fridge with no drain on the batteries, thats how I try to have my van set up going, solar is running the van and chargers for laptop, phones etc, batteries sitting at 100%............... if van is set up for off grid camping the 240v charger is redundant along with tug charging, just used as back up every year or so.
 
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Hitting the road

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Jan 14, 2022
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Brisbane
Evening all. Hoping for some quick advice.
just purchased a outback 17.56 2
Have optioned a non gas fridge, never been a fan of gas fridges.
just curious if anyone is using one. Have optioned 2 x 120 ah lithium batteries. Have the standard 150 watt panel on the roof and have a good portable 300 w to help charge. Hoping it should be enough to run off grid for a week or two.
cheers. Any advise be great.

Always have enough extra "panel" for the rainy day...or days. The standard 150w panel would likely be fine with the standard factory battery and a 3 way fridge, But optioning to more storage capacity and compressor fridge does definitely mean adding more "panel" as Drover suggests. Depending on your daily draw you might not get a week off grid in crappy weather without additional capacity available to feed back in.
I have increased the storage in my Jayco to 280w. but with AGM, and it still only has the stock standard 160w panel on the roof...though my van has the J35B BMS which is not Lithium compatible.
I do have up to 600w of extra panel that I can add externally if I need to, run through a separate MPPT controller as the J35B doesn't have the capacity. (it is 300w solar)
I think the J35D is rated to 450w solar input, but probably even if you had 600w of panel you'd be lucky to get to a reliable 450w going in anyway...