Model Boat Mayhem
Technical, Techniques, Hints, and Tips => DC Motors (Brushed) and Speed Controllers => Topic started by: rnli12 on August 02, 2017, 10:53:53 am
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Hi,
Does anyone know whether Fusion Aquapower Controllers will be okay with 6v or 12V SLA batteries.
Regards,
Rich
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Input Voltage NiCd/NiMH 5~10 Cells... so I'm guessing 10 x 1.2v = 12v but be careful, it doesn't have an 'SLA battery' setting and may discharge the battery beyond a safe cutoff voltage. {:-{
http://www.astramodel.cz/manualy/fusion/fusion_Aquapower128_manual.pdf
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Hi, am I being thick but I thought there was no "safe cut off voltage" for SLA battery's there is definitely one for lipo's and their ilk. Have I being doing it wrong for the last 30 od years.
Cheers Chipmonk
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Old wives tail?! {:-{
http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery
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Sounds like the jury is still out so will look at another brushed ESC %%
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When SLA was state of the art, there wasn't much call for warning circuits, partly because the circuit back then would be too big and cost too much, partly because the boat was its own warning device. When it slowed down, it was time to come in. The discharge curve was quite gentle, as opposed to things like LiPos where warning is minimal because they will give full current until it is too late.
Any ESC that says it will work on 5-10 NiMH cells should be just fine on 6 or 12 volt SLA. It neither knows nor cares where the volts and amps come from, as long as there are enough of both. If the battery is not capable of driving the boat in the first place, that's another story.
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It does a lead acid battery good to be drained and recharged now and again( deep cycled ) There are now sealed lead acid batteries which only need a recharge. No topping up needed and no leakage or fumes. If the boat can carry a lead acid battery of one sort or another well that's for me every time
Have a browse here .https://www.google.co.uk/search?q=lead+acid+battery&oq=Lead+acid&aqs=chrome.0.0j69i57j0l4.23795j0j7&sourceid=chrome&ie=UTF-8
A single cell gives app 2.1volts 6 cells 12.6volts approx and so on. However a question .I know a bulb in series will drop voltage but what if it's in parallel? Any or no effect? :} :-))
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Any lead acid can deliver an almost infinite current at least once, but for a short time, thats why cars have had working starter motors all these years. They are not good at over-heavy current for extended periods. As part of their chemistry, they do, under load, charging or discharging, do their best to vent gas. Even "sealed" ones. "Sealed for life" means that once enough of the contents have vented away, you have no means of replacing it, so it is then a dead 'un. Because they are an interleaved plate construction, under heavy load, the current though the plates in not evenly distributed. This results in uneven heating, with the attendant problem of potential warping, and uneven chemistry happening on the plate surfaces. This eventually finishes the battery.
They are generally OK with current at 1C, but intended for 0.1C. Pulling more does shorten their life expectancy, but when they were the only game in town, had to be used. Now there are alternatives that are designed to do better. A boat that requires modest current and is heavy, they are ideal, being relatively low cost and very recyclable. A same capacity or size NiMH will cost more, but weigh less, will deliver a heavier current longer, and will have simpler basic charging requirements until you want to fast charge.
Bulbs in series or parallel? In series they all draw the same current, and, if the same rating, get 1/n of the starting voltage where n is the number of bulbs in the chain. In parallel, they all get the starting voltage and each draws its own current. Provided that they are rated for either the starting voltage or more.
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Thanks Malcolm What ,if anything does it do to wattage?
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Thanks Malcolm What ,if anything does it do to wattage?
Wattage of watt?
Wattever the arrangement, power is still volts times amps. In series, they all get the same current, but if of the same rating, each gets its share of the available volts. In parallel, they all get the same voltage, but draw wattever current their rating demands.
Say you have two 12 volt, 12 watt bulbs and parallel them off a 12 volt supply - they both shine like they should and between them pull 1 Amp each i.e. 2 Amps. Same bulbs, same battery, in series, they both get 1/2 Amp, you might see them glow, each is using 3 watts.
Consider 6 volt 6 watt bulbs and the same 12 volt supply. Series, they pull 1 Amp and use 12 watts and having 6 volts each, glow nicely. Parallel, they briefly try to use 24 watts each, shine very brightly, and then you buy new bulbs.