WEC 2016, Camping, Power Box

Posted by under Electronics, on 26 June 2016 @ 9:40pm.

This blog is going to cover a number of things on my mind given I haven’t written a blog for a while. It’ll probably be a mish mash of all three since they’re all related in some way, so here goes…

So far this year I’ve been to 3 FIA WEC events, the first 3 in the season as it happens. It started in here in the UK at Silverstone for the first round. The second round took us to Spa in Belgium, and the third to Le Mans in France. I feel privileged to be able to attend so many of these events because I enjoy them so much. I live in an ideal area of the world that gives me access to 4 events – the places listed above plus the Nürburgring event added a few years ago.


All 3 of these events have been their own personal missions in some way or another. Silverstone I’ve done lots of times, but Spa was my first time this year. I have to say it’s a very difficult trip. Why? Well we travel there, watch the race, and travel home all in the same day. That means we’re awake for about 36-48 hours with little if no time to sleep. We could quite easily stay somewhere if we wanted to but if you can do it in a day then why not? It saves money and avoids needing time off work too. It’s definitely not something I would do every other weekend though – once a year tops! It really does take it out of you.

Le Mans. Now we’re talking. This has been my primary holiday of the year for a couple of years now as it’s a great way to spend time with friends whilst camping and enjoying racing, and on top of that getting to photograph them too. Not many people can say that their holidays let them enjoy 4 of their favourite activities in one go.

This year felt a little different though as we were one person short for the majority of the holiday. One of our friends wasn’t able to get the time off work so he only came up for one night, the night the race was on. As soon as it was over he was on his way back home again. It definitely felt odd with him not being there. He almost wasn’t the only person who wasn’t able to go either. One of our other friends almost couldn’t go because his holiday was rejected last minute by his work. Thankfully he managed to sort it out 2 days before we were due to go! Talk about cutting it close… He won’t make the same mistake last year so he’s booking it as soon as he can!


Now then, power box… I’m still planning upgrades to the power box because of what I’m about to talk about. I should add that it has been upgraded since my last post through the addition of 2 speakers and an amplifier in the front. We’ve wanted this ability for quite a while since music is something we all enjoy whilst camping, and speakers on mobile phones really don’t cut it. I got the speakers for free off a friend and the amplifier cost about £5 online. A little modification to attach it to the box and it was good to go. Definitely worth the effort.

We tried the speakers out for the first time properly at Le Mans, though we tried them in Silverstone successfully too. We kept it quiet though and because we weren’t near the track we couldn’t tell if the volume it was capable of would be enough to get over the top of the noise of the cars. We wanted this ability so we could put the radio broadcast through it. As it turns out, it was plenty loud enough for this at Le Mans.


Power consumption is quite high from this amplifier, and you can tell it’s not very efficient because it gets quite hot. I did some initial tests before I put it in the box and it uses up to 2A depending on volume and the audio being played. That could very easily kill the power box in just 24 hours if uses loudly without solar input. This is something we found out during the week at Le Mans this year. Come Friday we were at an unbelievably low 20% (11.00v) charge with just a couple of phones charging. I quickly made sure everyone was aware and we only charged phones if it was absolutely needed. I had a full 22,400mAh power bank available for my phone so I was in no desperate need of it.

Oddly, by Sunday we had managed to reach full charge again. I don’t know how though since only 18Ah of power had been put into it (unless it’s not been reported correctly on the display, but my testing did show it was relatively accurate), and some of that had been used charging phones and running the tent LED light. With a 50Ah battery that surely doesn’t add up. But hey ho, it showed 100% again and 12.8v under load which is indicative of a full charge. The green LED came on near the end of Sunday as well which indicates it hit 14.5v for at least 2 hours, again indicating a full charge.

In any case, I think a new solar panel next year is going to be needed. With mobile phones sucking more power, and us plugging in more things than ever before (charging power banks, charging up our hand held walkie talkies, and more), power is being drained more excessively than it was 2 years ago.


I plan on buying an 80w folding solar panel. This will be 2.6x more solar power that we currently have (30w at present). That should almost certainly be enough. It may even be more than we need, which is good in any case. Taking a lead acid battery below 50% doesn’t do it any good, and nobody likes it when power is low and you have to restrict your usage.

In order to use the 80w solar panel though I will need a new charge controller as well as the existing one is only capable of working up to 3A (36w) without getting far too hot. I am designing a new one which can cope with about 10A (120w) as a minimum which should allow for the 80w panel upgrade plus a bit more in the future.

It’s going to be an interesting project as I’m planning on making it into a monitoring controller as well. It’ll measure power going in and out of the battery as well as incoming solar power so we can see power consumption. At the moment it only measures the incoming power and not how much we have used. Because of this I can’t see what our typical power usage is so I can tailor the solar power to our needs. If I had that I could properly size the right solar panel instead of guessing. I’ve already ordered a fair number of the components for this so I can start work on it as soon as they arrive in the coming weeks.

Anyway, that’s all I’ve got for now. Watch this space for the next version of the charge controller, and maybe even a new power box front panel too.