Starcraft Jayco Outback Starcraft Solar

Drover

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That sort of seating arrangement has been on my list for a number of years now, finding the right chairs that fit my budget is the biggest hold up, if you do decide to go back to the Chiropractors Delight, the L shape lounge I'll have first dibs on your chairs then....... seems its got an uncomplicated set up, ability to put screens up all round is a very functional set up they not only provide shade can direct an air flow as well, using full size ones you can even throw a couple of tent poles under it for a make shift car port for those stinker of days when you don't want to park under the Cockies tree of choice....
My fridge is a RM4605, 2 door of 186lts, does a good job most of the time, freezer works really well, I have a Kings remote thermometer for it works well and if I keep the sensor inside out of the drip tray this time around it should be good for many years to come.... they are a pain thought as you watch it climb after a shopping run to local shops, especially the butchers...
 
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You're on Drover...let you know if I make the change...it looks a pretty easy fitment too with the brackets and support arrangement that have been made up. The seats just slide up and out for getting under them to the batteries mounted underneath.

The fridge we've got is a Thetford 2 door N3175E...196 litres in total I think. It must have been in an upgrade pack from Jayco when new, as they took the microwave oven from where it is normally situated above the fridge, and mounted it under the stove / grill diagonally opposite, being there is no oven.

The fridge has worked fine so far, cools reasonably quickly on mains and seems to hold the cool ok on 12v while on the move. Then to gas when off grid has worked a treat so far. But not knowing how it will go longer term with longer trips is why I am open to a compressor type fridge if warranted. I also need to get a remote temp gauge thing as you have so I can see what is going on in the fridge while driving...

I have been taking a portable fridge as well in the back of the tug when going away, mainly as a drinks fridge to keep the cans and bottles cold rather than opening and closing the fridge in the van. Plus when we go for day drives can keep the picnic chilled...

Great idea for the "carport" too...there was a handful of poles left with the van, but I have a stack of aluminum ones left from the camper days...
 
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Boots in Action

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You're on Drover...let you know if I make the change...it looks a pretty easy fitment too with the brackets and support arrangement that have been made up. The seats just slide up and out for getting under them to the batteries mounted underneath.

The fridge we've got is a Thetford 2 door N3175E...196 litres in total I think. It must have been in an upgrade pack from Jayco when new, as they took the microwave oven from where it is normally situated above the fridge, and mounted it under the stove / grill diagonally opposite, being there is no oven.

The fridge has worked fine so far, cools reasonably quickly on mains and seems to hold the cool ok on 12v while on the move. Then to gas when off grid has worked a treat so far. But not knowing how it will go longer term with longer trips is why I am open to a compressor type fridge if warranted. I also need to get a remote temp gauge thing as you have so I can see what is going on in the fridge while driving...

I have been taking a portable fridge as well in the back of the tug when going away, mainly as a drinks fridge to keep the cans and bottles cold rather than opening and closing the fridge in the van. Plus when we go for day drives can keep the picnic chilled...

Great idea for the "carport" too...there was a handful of poles left with the van, but I have a stack of aluminum ones left from the camper days...
@Hitting the road , some more info for you to consider regarding temperature gauge for your fridge. I have tried the companion- wired and wireless - and a couple of other types until I came across this one on Ebay. Link below.. It has two remote sensors and a third sensor in the main display unit. Sensor #1 I placed in freezer, sensor #2 in fridge area (clipped onto rack), and sensor #3 for ambient internal van temperature which is incorporated in the main display unit on wall of van for easy sighting. All 3 show current temp in real time, and also show and record the range of temps (highest and lowest) for the previous period since last re-set. Freezer has been down as low as minus 28.0C and van sensor as high as 40C, so big ranges catered for. Also shows temp "trend" indication by arrow whether stable, or climbing or cooling temps. All three can be set for "alarm" at selected min and max settings too. Apparently the receiving display unit can work up to 50 metres away although I have never tried that as unit remains in van approx 4 metres away from sensors. Massive advantages all the time and for around $25.00 when I bought it (cheaper at the moment!!!) , surpasses all the others I have tried. Needs 2 X AA batteries in sensors #1 and 2 and 2 X AAA in main unit. Batteries in sensors #1 and 2 last a long time with good quality alkaline batteries, but the main unit which has the displays on all the time not as long as the others. Also has battery level indicator. Chinglesh instructions are a pain, but this unit can be bought on Ebay from a Sydney distributor so quick delivery. Best investment I have ever made for fridge monitoring temperature without opening any doors!!! Also makes a great and useful present to your camping friends or even at home.

THIS IS NOT A PAID FOR ADVERT AND I RECEIVE NO MONETARY GAIN !!!!!

 
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Drover

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I don't think you will find the fridge wanting, the larger ones seem to run a bit better than the smaller jobs, again it all boils down to installation and power supply set up but from friends that off grid all the time and often and have had both types with proper set ups while they say the compressor is a little bit better certainly not worth $2K to swap out a perfectly good fridge, most 3 way problems are from poor installation.......................... I don't worry about monitoring the fridge while driving down the road, did once years ago and couldn't see the sense really as rarely on road longer than a few hours and if fridge has a power loss the rear view cam drops off line so I know.............
Some seem to think that if the fridge is at 4 deg its getting hot but 3-4degc for a fridge is actually normal and minus 12c or so for a freezer is good. but in an RV fridge these will change quickly when you restock especially if its warm stuff, putting the fridge temp monitor in the house fridge to compare is an interesting experiment, especially before and after the sho[[ing trip and when kids get home from school, it puts the van fridge panic into perspective....... The old school test is a ice cream .
 
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@Hitting the road , some more info for you to consider regarding temperature gauge for your fridge. I have tried the companion- wired and wireless - and a couple of other types until I came across this one on Ebay. Link below.. It has two remote sensors and a third sensor in the main display unit. Sensor #1 I placed in freezer, sensor #2 in fridge area (clipped onto rack), and sensor #3 for ambient internal van temperature which is incorporated in the main display unit on wall of van for easy sighting. All 3 show current temp in real time, and also show and record the range of temps (highest and lowest) for the previous period since last re-set. Freezer has been down as low as minus 28.0C and van sensor as high as 40C, so big ranges catered for. Also shows temp "trend" indication by arrow whether stable, or climbing or cooling temps. All three can be set for "alarm" at selected min and max settings too. Apparently the receiving display unit can work up to 50 metres away although I have never tried that as unit remains in van approx 4 metres away from sensors. Massive advantages all the time and for around $25.00 when I bought it (cheaper at the moment!!!) , surpasses all the others I have tried. Needs 2 X AA batteries in sensors #1 and 2 and 2 X AAA in main unit. Batteries in sensors #1 and 2 last a long time with good quality alkaline batteries, but the main unit which has the displays on all the time not as long as the others. Also has battery level indicator. Chinglesh instructions are a pain, but this unit can be bought on Ebay from a Sydney distributor so quick delivery. Best investment I have ever made for fridge monitoring temperature without opening any doors!!! Also makes a great and useful present to your camping friends or even at home.

THIS IS NOT A PAID FOR ADVERT AND I RECEIVE NO MONETARY GAIN !!!!!

Thanks Boots in Action for that info...I'll scout around...

I don't think you will find the fridge wanting, the larger ones seem to run a bit better than the smaller jobs, again it all boils down to installation and power supply set up but from friends that off grid all the time and often and have had both types with proper set ups while they say the compressor is a little bit better certainly not worth $2K to swap out a perfectly good fridge, most 3 way problems are from poor installation.......................... I don't worry about monitoring the fridge while driving down the road, did once years ago and couldn't see the sense really as rarely on road longer than a few hours and if fridge has a power loss the rear view cam drops off line so I know.............
Some seem to think that if the fridge is at 4 deg its getting hot but 3-4degc for a fridge is actually normal and minus 12c or so for a freezer is good. but in an RV fridge these will change quickly when you restock especially if its warm stuff, putting the fridge temp monitor in the house fridge to compare is an interesting experiment, especially before and after the sho[[ing trip and when kids get home from school, it puts the van fridge panic into perspective....... The old school test is a ice cream .
Thanks too Drover..this next trip away I'll be looking more at the fridge temps. So far so good, the freezer has been freezing water and keeping frozen stuff frozen. Like any fridge I guess the less it is opened the better it will perform...
 
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@Hitting the road , some more info for you to consider regarding temperature gauge for your fridge. I have tried the companion- wired and wireless - and a couple of other types until I came across this one on Ebay. Link below.. It has two remote sensors and a third sensor in the main display unit. Sensor #1 I placed in freezer, sensor #2 in fridge area (clipped onto rack), and sensor #3 for ambient internal van temperature which is incorporated in the main display unit on wall of van for easy sighting. All 3 show current temp in real time, and also show and record the range of temps (highest and lowest) for the previous period since last re-set. Freezer has been down as low as minus 28.0C and van sensor as high as 40C, so big ranges catered for. Also shows temp "trend" indication by arrow whether stable, or climbing or cooling temps. All three can be set for "alarm" at selected min and max settings too. Apparently the receiving display unit can work up to 50 metres away although I have never tried that as unit remains in van approx 4 metres away from sensors. Massive advantages all the time and for around $25.00 when I bought it (cheaper at the moment!!!) , surpasses all the others I have tried. Needs 2 X AA batteries in sensors #1 and 2 and 2 X AAA in main unit. Batteries in sensors #1 and 2 last a long time with good quality alkaline batteries, but the main unit which has the displays on all the time not as long as the others. Also has battery level indicator. Chinglesh instructions are a pain, but this unit can be bought on Ebay from a Sydney distributor so quick delivery. Best investment I have ever made for fridge monitoring temperature without opening any doors!!! Also makes a great and useful present to your camping friends or even at home.

THIS IS NOT A PAID FOR ADVERT AND I RECEIVE NO MONETARY GAIN !!!!!


Hi Boots in Action, I just ordered one of those Digital Thermometers you mentioned...thanks. They look pretty good for the price, will see how it goes. I'll also duck down to Jaycar and get one of their thermostats to go behind the fridge and a slightly bigger 120mm fan to fit at the top vent.
installation looks easy enough by tapping in to the 12v power feed to the fridge.

Cheers
 
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Boots in Action

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Hi Boots in Action, I just ordered one of those Digital Thermometers you mentioned...thanks. They look pretty good for the price, will see how it goes. I'll also duck down to Jaycar and get one of their thermostats to go behind the fridge and a slightly bigger 120mm fan to fit at the top vent.
installation looks easy enough by tapping in to the 12v power feed to the fridge.

Cheers
@Hitting the road , just be careful with your connection to a 12 volt feed. Remember, when operating off grid on gas, there will be no 12 volt line active to the main fridge element. You have a more modern fridge than my Thetford 93 litre. I connected my fan line direct to van battery using one of the existing fused lines that were available in distribution box. It is also has a switch in line for manual control. Your later model will probably have AES, so you will have to select the suitable line so 12 volt power is always available from your van battery when on 240 volt, 12 volt for travelling and especially gas. Good luck with your upgrades. Remember the KISS principle. You won't be disappointed with the fridge thermometer.
 
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@Hitting the road , just be careful with your connection to a 12 volt feed. Remember, when operating off grid on gas, there will be no 12 volt line active to the main fridge element. You have a more modern fridge than my Thetford 93 litre. I connected my fan line direct to van battery using one of the existing fused lines that were available in distribution box. It is also has a switch in line for manual control. Your later model will probably have AES, so you will have to select the suitable line so 12 volt power is always available from your van battery when on 240 volt, 12 volt for travelling and especially gas. Good luck with your upgrades. Remember the KISS principle. You won't be disappointed with the fridge thermometer.

Thanks for that...overlooked that while on gas...lol...though the fridge has an inbuilt internal 2 speed fan that is switchable on or off on the door, I'll have a close look when fitting it up, there may be a live 12v feed in back, if not I'll look at running it to one of the BMS outputs which supplies 12v all the time...
 
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jazzeddie1234

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.though the fridge has an inbuilt internal 2 speed fan that is switchable on or off on the door
Those fans work pretty well. I made sure they were clean and the airflow was forced over the fins by installing a baffle as described in the fridge install manual.

You can tap into their 12v feed to power another fan by looking for a set of spade connectors about 3/4 the way up the back of the fridge. 2 of these has a diode across so pick either of those (the 3rd is the earth ) - one side for switch pos 1 and the other for 11. I tapped into there to run my internal fridge fan
 
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Drover

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Thanks for that...overlooked that while on gas...lol...though the fridge has an inbuilt internal 2 speed fan that is switchable on or off on the door, I'll have a close look when fitting it up, there may be a live 12v feed in back, if not I'll look at running it to one of the BMS outputs which supplies 12v all the time...
The auto fridges have a 12v connector block at the rear one side is 12v from Tug and the other has 12v from Van, I think I mentioned it earlier, the fridge has a dedicated 12v feed from van batteries to power the fridge control unit, if it is disconnected the fridge is dead no matter what source you are using, there is also a "D+" lead it is 12v but will connect to the tug 12v source, it tells the fridge controller that the tugs 12v is connected, if this is disconnected you won't be able to run the fridge when yoou plug in your tug, trying to figure out why can drive some nuts .... So you will be able to connect fans to the 12v House source at back of fridge, I ran a small cable thru the conduit that feeds the control panel at front of fridge so I could fit a micro switch for my fans............ My internal fan I just tapped into the light feed....
 
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I mentioned it earlier, the fridge has a dedicated 12v feed from van batteries to power the fridge control unit

That makes sense as the unit apparently auto seeks what power source is available and switches to it...including gas as it will self light. If it doesn't auto find the best source the touch pad on the front can be pointed to gas, 12v or 240v. First time i switched to gas though I had to point to it via the touch pad before the gas would light.

I am surprised that the Jayco wiring set up when plugged in to the tug only powers the fridge, and doesn't poke any power in to the batteries. But being there is the solitary 160w solar panel on the roof, I would assume it would still feed the batteries while in transit?
I hadn't looked at what the control panel was doing, which I will do next time out, as the control panel should show some feed in to the batteries to keep them full I would have thought.

When we were parked up off grid at Kingaroy last outing the control panel showed intermittent solar input, but I am assuming the intermittent bit was due to the batteries being full....it would have been just floating as the control panel at the time also showed 198 hours left in the batteries at the current usage. (full)

I'd reset the BMS for the original battery capacity of 100 amp up to the new 280 amp capacity so it was reading correctly....hence the 198 hours left...I'd previously calculated that we could go for about 8 days off grid with no external power input at all, so that was about right with the fridge and water heater on gas.
 

jazzeddie1234

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Jayco wiring set up when plugged in to the tug only powers the fridge

In my case it does both. A pin in the 7 row (pin 2 I think) powers the breakaway controller, the antisway, and a feed to aux in on the setec which charges the batteries if the tug voltage is high enough.

The setec aux in is a bit crude in design - a simple diode and no current limit - and the pins in the 7 row are around 10amps max. You can work around this but make sure to add up all the demands on the tug alternator (especially with a high current fridge) before adding anything
 
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Drover

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I mentioned it earlier, the fridge has a dedicated 12v feed from van batteries to power the fridge control unit

That makes sense as the unit apparently auto seeks what power source is available and switches to it...including gas as it will self light. If it doesn't auto find the best source the touch pad on the front can be pointed to gas, 12v or 240v. First time i switched to gas though I had to point to it via the touch pad before the gas would light.

I am surprised that the Jayco wiring set up when plugged in to the tug only powers the fridge, and doesn't poke any power in to the batteries. But being there is the solitary 160w solar panel on the roof, I would assume it would still feed the batteries while in transit?
I hadn't looked at what the control panel was doing, which I will do next time out, as the control panel should show some feed in to the batteries to keep them full I would have thought.

When we were parked up off grid at Kingaroy last outing the control panel showed intermittent solar input, but I am assuming the intermittent bit was due to the batteries being full....it would have been just floating as the control panel at the time also showed 198 hours left in the batteries at the current usage. (full)

I'd reset the BMS for the original battery capacity of 100 amp up to the new 280 amp capacity so it was reading correctly....hence the 198 hours left...I'd previously calculated that we could go for about 8 days off grid with no external power input at all, so that was about right with the fridge and water heater on gas.


You will find that the firing up on gas will not happen straight away there is a delay especially when coming from 12v, this is so if you stop at a garage to refuel, the 12v from tug shuts off and since some don't turn off the gas the Auto fridge otherwise would fire up the fridge on gas, so you would have a igniter trying to fire up a flame, hence the 10 in or so delay .............. Gas should always be turned of once you hook up, never drive with it on...

If you have an anderson from tug to fridge probably a direct line, if no charge from tug to van batteries its not a biggy really with a panel on the roof certainly not worth the $$$ to get it fitted.

The solar should look after the battery while driving, if on a normal day it can't then its not going to be very much use in camp I always think, don't put a lot of store in these hours left results, do an audit of your power use by hooking up a meter or your display may show useage use that, turn everything off and see if theres any drain, then turn each item on and see the draw, turn off and do another, then do the math on how much use a day, add them all together, the total guestimated daily use should be, in my book it, no more than 40% of your storage with AGM's or GELs, so in the morning you should really have around 75% left in batteries, this allows for those yuckky days , doesn't flog the crap out of your batteries, by the time I get mobile my panels are just idling away with hardly any feed, give a few days of solid cover and by day 2 I will cut back use a bit to make things stretch out as I don't want to drill beyond the 50% charge if I don't really have to......... Mostly though my set up like a house set up all power use is provided by the panels as the batteries stay at full charge, start to draw from batteries later in day depending on portable panel position..... Big Mal usually only has external power a couple of days before departure when we fire up the fridge and the odd time we do plug into 240 its for the fridge, battery charger rarely if ever gets used and not possible to charge from tug..
 
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In my case it does both. A pin in the 7 row (pin 2 I think) powers the breakaway controller, the antisway, and a feed to aux in on the setec which charges the batteries if the tug voltage is high enough.

The setec aux in is a bit crude in design - a simple diode and no current limit - and the pins in the 7 row are around 10amps max. You can work around this but make sure to add up all the demands on the tug alternator (especially with a high current fridge) before adding anything
I probably need to do a multi meter check on what is coming from the various pins in the Anderson plug on my tug. The 12 pin plug was fitted when I bought it, as well as a separate feed to an anti sway set up, though my van isn't fitted with anti sway. The alternator is a 220 amp so should handle any load imposed anyway I would imagine...
 
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You will find that the firing up on gas will not happen straight away there is a delay especially when coming from 12v, this is so if you stop at a garage to refuel, the 12v from tug shuts off and since some don't turn off the gas the Auto fridge otherwise would fire up the fridge on gas, so you would have a igniter trying to fire up a flame, hence the 10 in or so delay .............. Gas should always be turned of once you hook up, never drive with it on...

If you have an anderson from tug to fridge probably a direct line, if no charge from tug to van batteries its not a biggy really with a panel on the roof certainly not worth the $$$ to get it fitted.

The solar should look after the battery while driving, if on a normal day it can't then its not going to be very much use in camp I always think, don't put a lot of store in these hours left results, do an audit of your power use by hooking up a meter or your display may show useage use that, turn everything off and see if theres any drain, then turn each item on and see the draw, turn off and do another, then do the math on how much use a day, add them all together, the total guestimated daily use should be, in my book it, no more than 40% of your storage with AGM's or GELs, so in the morning you should really have around 75% left in batteries, this allows for those yuckky days , doesn't flog the crap out of your batteries, by the time I get mobile my panels are just idling away with hardly any feed, give a few days of solid cover and by day 2 I will cut back use a bit to make things stretch out as I don't want to drill beyond the 50% charge if I don't really have to......... Mostly though my set up like a house set up all power use is provided by the panels as the batteries stay at full charge, start to draw from batteries later in day depending on portable panel position..... Big Mal usually only has external power a couple of days before departure when we fire up the fridge and the odd time we do plug into 240 its for the fridge, battery charger rarely if ever gets used and not possible to charge from tug..

Yeah, I make sure the gas is turned off at the bottles as part of my pre flight checks....and check that the fridge has flicked over to 12v once the tug is connected. I was curious as to why the van batteries weren't being charged by the tug though, as the various blogs I have read indicate that the Anderson plug on the Jayco van only feeds the fridge due to it's high amperage while using 12v..

I haven't had the opportunity to do much observation on the whole setup yet...the weather has been crap week in and week out so haven't been going anywhere....plus no value trying to work on the van in pouring rain. Might as well sit inside comfortably at home while it buckets rather than in the van somewhere! ...besides my work keeps getting in the way of pleasure all the time.

Like you I have always ensured I have enough solar to have the batteries back to 100% by mid morning,...in the mornings with the same setup in the camper trailer as the van has now, but with far more power use as I was running both a 65L fridge and a 45L freezer plus lights etc on the same 2x140 amp AGM's, which would see the batteries at average 80% in the mornings...before any solar input.
By 10am they'd be at 100% again and float charge all day.
Right now the van's current draw is peanuts off grid as there are only LED lights, and a bit of water pump, that's it. Once I get the Inverter fitted though the picture will change some what.

That's the reason i have added the external solar capability, for as you wrote, those days where the sun don't shine, and power is still being consumed. I can make sure it pumps amps back in quickly on the better days if I need to being I now have up to 760w of solar available if I ever need it.

I am fortunate that at the mates place where I keep the van it is plugged in to 240v 24/7 which keeps the batteries charged. I have only gone over there a day or two before we went gone away to restock the cupboards and turn the fridge on at 240v so it cools. Then when we have taken off the batteries have been chocker...
 

Boots in Action

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I probably need to do a multi meter check on what is coming from the various pins in the Anderson plug on my tug. The 12 pin plug was fitted when I bought it, as well as a separate feed to an anti sway set up, though my van isn't fitted with anti sway. The alternator is a 220 amp so should handle any load imposed anyway I would imagine...
@Hitting the road, you will find all that @Drover said correct and that pin #2 on 12 pin (or 7 pin) is originally for the reversing lights from tug to van. However, whilst this was satisfactory for the earlier vans which did not have a battery, it did not allow for a connection between tug and van battery for use, or vehicle charging. So, some in an effort to avoid having to run a new line, decided to disconnect the tug line from tug connector #2 (thus keeping the reversing lights on tug) and ran a separate line from tug battery to pin 2 on tug connector. This connected to pin 2 on van connector which is the aux input to Setec. However, to prevent the van battery (and tug wiring) being involved with the tug battery when heavy current needed when starting tug, a power diode was placed in the aux line to prevent van battery from being discharged at the same time. This benefit causes a loss of approx 0.7 volt on any input from tug charging via aux input line. This applies to Setec models Series I, II and III. Later model BMSs have a different system of isolating the van battery from the tug without a voltage drop. Also as @Drover said, wiring for pin #2 is only 10 amp or maybe 15 amp at best so NOT suitable for fridge loads. So that is why fridge connections are through pins #9 and 10 which are heavier pins capable of handling 35 amps if wiring is suitable. A lot of vanners have a fully dedicated heavy line from tug to Anderson plugs direct to fridge input lines to avoid voltage drop in line to fridge, (pins #9 and 10 not used then ) and pin #2 still connected to Setec input line. Modern tugs with smart alternators have caused further hassles because alternator voltages are not high enough to charge van (or any auxiliary battery) and there is then the need for a DC to DC charger if van/auxiliary battery/ies are to be charged by tug. All these changes due to "modernization".
 

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@Hitting the road, you will find all that @Drover said correct and that pin #2 on 12 pin (or 7 pin) is originally for the reversing lights from tug to van. However, whilst this was satisfactory for the earlier vans which did not have a battery, it did not allow for a connection between tug and van battery for use, or vehicle charging. So, some in an effort to avoid having to run a new line, decided to disconnect the tug line from tug connector #2 (thus keeping the reversing lights on tug) and ran a separate line from tug battery to pin 2 on tug connector. This connected to pin 2 on van connector which is the aux input to Setec. However, to prevent the van battery (and tug wiring) being involved with the tug battery when heavy current needed when starting tug, a power diode was placed in the aux line to prevent van battery from being discharged at the same time. This benefit causes a loss of approx 0.7 volt on any input from tug charging via aux input line. This applies to Setec models Series I, II and III. Later model BMSs have a different system of isolating the van battery from the tug without a voltage drop. Also as @Drover said, wiring for pin #2 is only 10 amp or maybe 15 amp at best so NOT suitable for fridge loads. So that is why fridge connections are through pins #9 and 10 which are heavier pins capable of handling 35 amps if wiring is suitable. A lot of vanners have a fully dedicated heavy line from tug to Anderson plugs direct to fridge input lines to avoid voltage drop in line to fridge, (pins #8 and 9 not used then ) and pin #2 still connected to Setec input line. Modern tugs with smart alternators have caused further hassles because alternator voltages are not high enough to charge van (or any auxiliary battery) and there is then the need for a DC to DC charger if van/auxiliary battery/ies are to be charged by tug. All these changes due to "modernization".

Hmmm, ok. You are certainly all over this stuff Boots in Action, very comprehensive and knowledgeable...thanks.

My tug does have a "smart" alternator, though imo a pretty dumb alternator really as it reduces power output when the starter battery has supposedly recovered voltage from starting, so pretty useless to tap directly in to. Good for businesses like RedArc though. The .00005% difference it would make to fuel consumption due to the load...really?

Therefore I had to fit a 25 amp RedArc BCDC charger hard wired in to the tug which constantly charges the aux battery. Back when towing the camper trailer I used a "Y" connector to connect both the camper trailer and the tug's aux battery to this charger while on the run, being the camper trailer had a freezer running in it all the time it would keep that battery topped up too. I ran the other fridge off the aux battery in the tug.

I guess if the Anderson plug wiring goes straight to the fridge and doesn't go near the batteries then there can be no drain anywhere on start up. The fridge will only fire once the 12 volts and amps begin to flow...there must still be enough amperage coming out of the "smart" alternator to power the fridge as so far it has operated fine on the run. I wonder whether the additional load of the fridge fools the ECU in to thinking the battery is still requiring higher input so it keeps the amps flowing?

The reality is too I s'pose, being there is a solar panel on the van chugging away while on the move dumping in to the house batteries, and there is no house battery drain as the fridge so far has operated fine through the existing 12v Anderson plug arrangement, probably no need to change anything. The van batteries won't lose anything between home and camp. As they say...if it ain't broke...

(If I ever do need to charge the van batteries off grid I can always crank up the generator should the solar fail me for some reason...)
 
Jan 14, 2022
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Brisbane
If your going to do off grid and have roof top solar then no need for 12v from tug... Does the alternator on these modern rigs a favour actually.

i wondered about that...is there really no need to use the alternator to run the fridge when the batteries constantly receive some constant charge from solar? Though likely only maybe 6 amps per hour over 5 hours from the 160w panel fitted.

Though reading the specs of the Thetford I have, it reads that the power usage over 24 hours is huge...I'm not all over this stuff, but using online calculators that seems to equate to close to 14 amps per hour on 12v! Is that possible given my 12v camper fridges are lucky to use 3 - 3.5 amps an hour when cooling or have I got that all wrong?
Admittedly these aren't a small compressor fridge like the camper fridges are, but absorption which means to me the 12v input has to constantly heat an element to heat the refrigerant to operate the fridge.

Thetford N3175 Energy consumption Kwh/24h = 4.0

The vehicle alternator would easily supply 14amps constant if that's whats needed...
 

Boots in Action

Well-Known Member
Mar 13, 2017
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Ferny Grove, Queensland
If your going to do off grid and have roof top solar then no need for 12v from tug... Does the alternator on these modern rigs a favour actually.
@Drover, there is no way a single 160w solar panel can meet the constant demands of a 3 way fridge requiring more than 14 amps at 12 plus volts constantly. Okay to try to keep storage battery topped up when fully operating, but at 5 amps and varying all the time on the road - shadows and non optimal direction - no way. Even with 15 amps solar capacity, this input is not constant and always needs the back up of some sort of storage system eg battery voltage and current.