desertrover
Adventurer
Install looks good! You'll love the PV when you're living out of your rig. Are you still planning on installing a small fridge?
Just installed my solar panel on my van.
- Thread starter Basement Yeti
- Start date
Basement Yeti
Explorer
Thanks.
I'm not sure. My original plan was to get a small thermoelectric unit. But after some research I discovered they are power hogs, the best can only cool 40 below the ambient temperature, and those are around 100 a piece.
The fridges posted on here are really expensive, and all of them are far too large for my needs. 20Qt max is what I'd be looking at.
But I just can't justify the cost of 400-1,000 dollars to chill some soymilk, hummus or lentil dip, some fruit, etc.
I did go a bit over kill on my solar panel. Especially being here in San Diego. I went to check on the van today and noticed the meter was only reading .43A. I checked the batteries and both were completely charged and bulked up.
This was at 12PM.
It'd be silly for me not to get a fridge and an inverter to properly utilize this investment.
I'm not sure. My original plan was to get a small thermoelectric unit. But after some research I discovered they are power hogs, the best can only cool 40 below the ambient temperature, and those are around 100 a piece.
The fridges posted on here are really expensive, and all of them are far too large for my needs. 20Qt max is what I'd be looking at.
But I just can't justify the cost of 400-1,000 dollars to chill some soymilk, hummus or lentil dip, some fruit, etc.
I did go a bit over kill on my solar panel. Especially being here in San Diego. I went to check on the van today and noticed the meter was only reading .43A. I checked the batteries and both were completely charged and bulked up.
This was at 12PM.
It'd be silly for me not to get a fridge and an inverter to properly utilize this investment.
wrcsixeight
Adventurer
There are plenty of people who run a dorm style Home Depot bought 120$ compressor fridge from an Inverter. Even MSW inverters.
It is not as efficient as a 12 volt model, and might not last as long with vehicle vibrations but at 1/10 the price of an AC/DC fridge is a very viable option. Just figure out a way to secure the door while driving, and get an inverter that uses very little juice when not providing any electricity to the fridge when the compressor is not running.
My AC/DC Norcold Fridge, in the last 4 years has paid for itself many times over in terms of Block Ice and the gas required to get more every 5 days. Factor in the convenience and not having ziplock bags filled with cooler water and the return increases yet again.
Congrats on the solar set up. I love having 130 watts on my roof, keeping my beer at 34 degrees.
Basement Yeti
Explorer
Hey thanks, I might look at getting a little dorm fridge. I am a city van dweller these days, mostly. So I think it would be ok as a temp solution.
I'm just trying to save my money because I want to buy a few acres of land in nNorthern AZ in a few years.
I'm just trying to save my money because I want to buy a few acres of land in nNorthern AZ in a few years.
Basement Yeti
Explorer
Remote meter shenanigans.
Yesterday I went to the store for some lunch and decided to eat in my van, but since it was hot I left it running along with the A/C.
While I as sitting on my bed eating I noticed the meter read 35.85A.
I wonder if the meter was reading the alternator amperage and the the solar panel amperage combined?
Yesterday I went to the store for some lunch and decided to eat in my van, but since it was hot I left it running along with the A/C.
While I as sitting on my bed eating I noticed the meter read 35.85A.
I wonder if the meter was reading the alternator amperage and the the solar panel amperage combined?
dwh
Tail-End Charlie
Don't think so...
The meter just connects to the charge controller, and there is no shunt on the negative, so it should have no way to know how much is flowing into the battery from the alternator. The charge controller only knows how much is flowing through it.
That's whacky. I'd drop a line to Morningstar tech support and ask ******?
The meter just connects to the charge controller, and there is no shunt on the negative, so it should have no way to know how much is flowing into the battery from the alternator. The charge controller only knows how much is flowing through it.
That's whacky. I'd drop a line to Morningstar tech support and ask ******?
wrcsixeight
Adventurer
I have a monitor which is wired to read alternator amperage. If my engine is hot and my batteries are thirsty, at idle speed, I consider myself lucky to see 27 amps, and I have an undersized Alternator pulley and oversized charging wire.
I was gonna say 35 amps at hot idle with the AC on is pretty impressive, but you have other issues.
I was gonna say 35 amps at hot idle with the AC on is pretty impressive, but you have other issues.
Basement Yeti
Explorer
wrcsixeight
Adventurer
Reading alternator amperage means all the negative cables must go to one side of the shunt, and only the batteries are connected to the other side of the shunt. Nothing else is connected to the battery negative.
http://www.solar-electric.com/mkb-500-50.html
There is a shunt in your charge controller which measures only the output of the solar array. Alternator amperage does not pass through this circuit and will not be read
http://www.solar-electric.com/mkb-500-50.html
There is a shunt in your charge controller which measures only the output of the solar array. Alternator amperage does not pass through this circuit and will not be read
dwh
Tail-End Charlie
To measure amperage, the amps have to pass through the measuring device. If you had a meter like a LinkPro or a Bogart, then you would put a shunt in the negative line to the battery, and be able to measure *all* current flow in to, and out of, the battery.
But the SSD doesn't use a shunt, so it cannot know everything that goes into the batteries, and it knows nothing about what goes out of the batteries. All it knows is how much current flowed through *it* to the batteries, and the battery voltage.
Since the current from the alternator to the battery doesn't pass through the charge controller, it shouldn't be possible for the charge controller to measure that current.
After sleeping on it, the only thing I can come up with is that since it's a dual controller and connected to both batteries, it might somehow be measuring the flow from one battery to the other.
That doesn't really make sense though, since it would still have to have the current flowing through it, and I don't think it allows current from one battery to go through it to the other.
It's whacky, and that's why I'd ask Morningstar to figure out exactly what's going on.
The thing was pretty much designed for RVs, many of which use split-charge relays, so they must already know exactly what happens in that situation.
Another thing that's a little screwy, is that you reported seeing 35a on the meter...but that's only a 25a charge controller. I hate to say it, but are you sure you read it right? 3.5a from the solar would make sense with the engine running - but 35a doesn't make sense in any way I can think of.
Also, the meter doesn't measure anything. All it does is display whatever information the charge controller gives it.
But the SSD doesn't use a shunt, so it cannot know everything that goes into the batteries, and it knows nothing about what goes out of the batteries. All it knows is how much current flowed through *it* to the batteries, and the battery voltage.
Since the current from the alternator to the battery doesn't pass through the charge controller, it shouldn't be possible for the charge controller to measure that current.
After sleeping on it, the only thing I can come up with is that since it's a dual controller and connected to both batteries, it might somehow be measuring the flow from one battery to the other.
That doesn't really make sense though, since it would still have to have the current flowing through it, and I don't think it allows current from one battery to go through it to the other.
It's whacky, and that's why I'd ask Morningstar to figure out exactly what's going on.
The thing was pretty much designed for RVs, many of which use split-charge relays, so they must already know exactly what happens in that situation.
Another thing that's a little screwy, is that you reported seeing 35a on the meter...but that's only a 25a charge controller. I hate to say it, but are you sure you read it right? 3.5a from the solar would make sense with the engine running - but 35a doesn't make sense in any way I can think of.
Also, the meter doesn't measure anything. All it does is display whatever information the charge controller gives it.
Basement Yeti
Explorer
Must have been a fluke. I checked today and the meter dropped to 0 Amps when I started the van.
wrcsixeight
Adventurer
When my batteries are at ~95% and above, my charge controller will usually go open circuit and contribute nothing to the batteries. when I start my engine.
But not always. It depends if the voltage regulator in my engine computer decided to allow 14.8 volts, or not.
But not always. It depends if the voltage regulator in my engine computer decided to allow 14.8 volts, or not.
Basement Yeti
Explorer
I'd like to see your rig sometime. You talk about it often.
wrcsixeight
Adventurer
Cruise up to North County, I'll show it to you. I just put new Tires on it today. Finally.