Vanelec auto electrics and off grid

Another caravan solar modification complete. Customer reports substantial increase over existing setup. Call me to see if I can solve your caravan electrical problems or design you a new system. Thanks Caravanning and camping Oz for your business.

“Can you make my brake controller work?”Maybe this is something to do with the problem 🤣

It’s important to use the correct terminal on the end of a cable. Here’s some found on a customer’s vehicle that was having trouble charging their caravan.

✅ cable is the correct size
❌ terminals are way too small and most of the cable can’t fit in.

Years of additions to a 10 year old caravan result in this kind of wiring (first pic). Some with no fuse, some dangerous additions.

Trust VanElec to fix the power problems and make it more presentable, fused and actually work effectively.

New Victron solar regulators and 240V chargers.

✅Fix the power system
🚍Enjoy your travels!

Base6 lighting is now available for installation and sale from VanElec. Ask us for a demonstration.

I've had lots of people asking me recently why their solar is not working properly. We are currently in Darwin and this (picture) is the solar output in watts of our Sunman eArc 430W flexi panel. You see peak generation is just shy of 250W. We have a mix of flexi and glass panels on our van, they all exhibit exactly the same symptoms: 40% reduction in solar output. It's quite normal in this low winter sun and if you're in Darwin or anywhere hot it's a problem as you have less solar but more heat. Still it's better than a cold winter🥶

Your solar probably isn't faulty, but it's always worth routinely checking tightness of all connections, crimps and terminals as well as cleanliness of panels. Or get a professional to check if you're not confident!

Anderson connectors sit at the back of your vehicle and collect all sorts of dirt. They get corroded too and this all increases the resistance in the circuit.

We had to change some recently because they had just gone beyond help.

It’s possible to remove the pins with the wire attached and clean them off. Just remember to remove the fuse first!

Battery series: PART 1 How much battery capacity do I need for my 12V loads?

In today’s post we are looking only at 12V DC loads, not anything running on the 230V AC or about solar or generators. More on that later on.

STEP 1:
Make a list of everything running from 12V in your van, preferably on a spreadsheet. Be specific and write each light separately, or each group of lights if they work from one switch. See the end for a common list of missing items.

STEP 2:
Work out how much current each device uses. You can do this by turning on only that one light, TV or radio and looking at your amp meter on your power control system if you have one. If you don’t you might need:
- a DC clamp meter
- to look at the manufacturer’s specification
- to ask a professional
- find knowledgeable friend
Remember when you do this, check the value is 0 to start with and make sure your 230V charger and solar is off (do it in the dark)

STEP 3:
Write the amount of amps used in one column and write the number of hours each day you will use this device. For example if my LED light uses 1.5A and I use it x 4 hours each day then 1.5 x 4 = 6Ah (Amp hours)

STEP 4:
If you have a compressor fridge look at the manufacturer’s rating (otherwise ignore this step). Normally it will say something like 50Ah per day at 32°C. Adjust up or down for your ambient temperature. I find +5% per °C above their standard rating works ok. Note if your fridge tells you 670Wh per day (for example) then this is in watt hours and you should divide this by 12: 670/12=55.8Ah. You can also find fridges rate their use per hour, so you would need to multiply this by 24 hours in the day of course.

STEP 5:
Phone chargers are a bit more complex:
If your USB outlet says something like 2.5A (Amp) output then this is 2.5A at 5 Volts (the standard voltage for USB) so we can work out the power in WATTS: 2.5A x 5V = 12.5 Watts.

Now to get the 12V rating in Amps we divide 12.5 Watts by 12 Volts to get (about) 1 Amp. Multiply this by the number of hours per day you use that charger. So lets say it’s in use 6 hours per day across multiple devices that’s 6A x 6 Hours = 6 Amp Hours (6Ah)

If your charger is rated in watts, you can skip the first bit.

Don’t forget to do this for each USB outlet or each place you have a 12V to USB adapter plugged in.

It gets more complex with USB-Power Delivery. Let’s keep this simple for now and pretend that doesn’t exist.

STEP6:
Now you have a list of everything you use and how long each day it is used for you can add up all the lines and you might get something like 54Ah (Amp hours). Now you need to decide the number of days you want to live autonomously without charging the batteries. Let’s say I want 3 days without any charge.

If you buy a Lithium battery you would think a 54x3=162Ah battery would do, but 20% of the battery is never used to protect the cells so over specify up to the next available size of 200Ah.

If you buy an AGM battery it’s worse in that only 50-60% of the capacity is really useable before the voltage drops too low. So I would specify 154Ah x 2 = 308 Ah.

It all adds up when you really look at it this way.

Some common things you might forget about are:
- kitchen extract fan
- bathroom extract fan
- awning lights
- water pump (notable use is from showers or filling the washing machine)
- 12V TV
- Radio
- USB powered bug zapper (a great invention)
- Torch chargers

Making sure your batteries are charging properly in your canopy or caravan is important. If you don't have a built in monitor to give you some information, make sure you carry a multimeter. Even the cheapest one for $10 would help us to help you remotely, wherever you are in Australia!

If you're stuck with something not working and you don't have anyone local to help out, send us a message on FaceBook Messenger. It's amazing the amount of things that can be diagnosed or fixed remotely.