Known Unknowns and Unknown Knowns

I was working with the solar system on the bus today and these are my findings....

• The LED charge controller gets to a certain battery high charge point then starts pulsing the supply from the solar panels.
• The LED charge controller get to a certain battery low charge point then starts pulsing the power from the battery
• The watt meter does work and reads correctly. When little power is being used, it tells me (confusingly) that there’s very little wattage. 
• The two 30W panels do produce at least 50W between them (maximum measurement point)
• An MPPT controller is likely to set me back over $120.
• A cheaper MPT charge controller is likely to be as bad as my existing MPT controllers.
• My blue digital charge controller throws a wobbly when the fans come on.
• I should have enough power from the panels to be able to run my ventilation fans straight from the panels.
• The batteries deplete when using the ventilation fans despite there being plenty power.
• The battery depletes rapidly but charges rapidly
• The battery is about 18 months old.
• I’m getting rather frustrated with the problems
• An LED bulb blew
• I need to install my rear solar input
• Maybe I need to install a mains trickle charge option for the battery.
• The portable solar panels are OK placed on the hood. 
• I managed to get one of the cigarette lighter plugs soldered.
• The cigarette lighter to SAE adaptor I ordered is still sitting in New York (according to the USPS website), having arrived there on the 24th. It has until July 17th to arrive so if it’s not here by Junly 18th I’m filing non arrival.
• A better place to house the house battery would have been the existing battery compartment. It can house 3 group 31 batteries. I only use two for driving.
• The amp/watt rating on a charge controller is controlling the amount of power that can be taken out of the battery. 

The bus is complete aside from sorting out teething issues such as the solar power. After the solar power there’s a buzzing relay under the hood and a power leak. Those two are probably linked. Other than that, the turn signal switch needs work and there’s a strange wire dangling under the bus that needs removal. The oil pan gasket needs to be changed and since the oil is 4 years old that too.

Resolutions (which may change with my mood)

• Replace the charge controller. If I can get a Harbor Freight 500W controller cheap then I’ll do that but it has to be under $20. Otherwise it’ll probably be an MPPT controller.
• Replace the LED bulb
• Install my rear solar entry.
• Chuck out all the cheap Chinese charge controllers and put a bullet through each one lest I be fool enough to pick them out of the trash and try them again.
• If the battery is toast then rather than buying a 35AH battery for $50-$70 at Harbor Freight, buy a 125 AH battery from Walmart and locate it inside the driving battery compartment rather than where my current battery is located.
• In the case of battery replacement, Install another line to power the fans directly from solar.

And I’ll probably moan about it all on whatever social media that I use. The solar panels do look quite pretty on the hood. I do believe though that the problems right now as far as the battery and ventilation lie squarely at the door of the charge controller and possibly the battery too. If it’s a dead battery then the cheap charge controllers killed it. 

Despite what I said yesterday about adding extra batteries, a quick calculation ow what tow well sited 30W panels will do is that at 50W they will produce over 5 hours, 250WH or 20AH of electricity. Add in what the other 35W produces and it’s sufficient. 20AH would power my extraction fans for 4 hours straight.

I’m thinking that because I don’t get many minutes from my 35AH battery, the cheap charge controllers have probably fried the battery. Now the advantage of the house battery in the main driving battery compartment is I can disconnect the driving battery as normal and if I need to jump start - it’s right there - I can jump the bus off the house battery or connect the house to the bus batteries to keep them all topped up when the bus is parked up.