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Car Battery Power help

Started by tomatofish1, Nov 23, 2016, 02:01 pm

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Hi I was wondering if anyone might be able to help me with this question I have got all my sound to light set up to a 12 volt car battery but i was looking to connect this http://www.ebay.co.uk/itm/12V-4CH-Channel-200M-Wireless-Remote-Control-Relay-Switch-Transceiver-Receiver-/131730091890?_trksid=p2141725.m3641.l6368 in to the battery so it would turn all power off to the equipment wireless the only problem i need help with it how do i stop the battery draining as it would have to keep power to the  Wireless Remote Control Relay Switch Thank you Hope someone might be able to help Thank you


Car batteries are great if you need cordless/mobile power, but I've usually used those little wall-wart plug-in 12V power supplies that go for about £10-15. They plug into the mains and give you an 1A or 2A of current (which is 1000-2000mA)

If you go with a car battery, make sure you have a fuse inline. A car battery is designed to start an engine and so can produce enormous current. Which means potentially enormous heat - enough to melt down bus bars and easily start a fire if you get a simple short circuit. A fuse will go if that happens. So some care is required. You can buy the fuses in any car part shop, e.g. Halfords. They may even have the fuse holders.
I'm not really very knowledgeable about cars, so other people on here may be able to give better advice.

People with daleks often use the 'leisure battery' size (for the dalek voice box), which is much smaller and lighter. It won't hold as much or produce as much current, but you'd still want a fuse, I would think.

The gadget you linked to has a 'quiescent condition' current requirement of less than 6mA. A car battery will usually store about 80Ah, which is 80000mAh, so will keep your device alive for 13000 hours in theory. Which is about a year and a half.
You'd probably want to charge it up with a battery charger every few months.

A plug-into-the-mains power supply is much easier though. And much cheaper than a new car battery.

Hope this helps.


Nov 23, 2016, 02:58 pm #2 Last Edit: Nov 23, 2016, 03:03 pm by tomatofish1
Thank you so much for your help its as helped mew out big time Thank you so what sort of car battery am i looking for also i will be plugging in to the item i linked about a couple of led lights and a small amp and a sound to light controller that wont be on all the time thank you


If you want to go the battery route, I would start with one of the small 12V lead-acid batteries. You can get 7Ah batteries that are about 6 inches by 2 inches by 3 inches that would still keep you on standby for about a month. This is what people typically use in a dalek for the sound board.


Thank you all  for your messages