mooman999

New Member
right then, im looking to run a few things on my truck and i was wondering whether or not it would be worth running a split charge system or not. im going to be running 6x55w spotlights, a stereo, a sub and amp a rear exterior light and interior light along with a few little low power things. thanks, mat
 
You have 27.5 amps just on the spot lamps, before you have started with sidelights, stereo, amp, sub and rear light, I'm thinking of doing similar, just so I can use the stereo and lights if I'm ever camping, or working on it (Without worrying about it not starting) :D
I also have rooflights, amp and sub so I think it would be wise, got a 70amp alternator to go on as well eBay - The UK's Online Marketplace
 
you'd need to spec up all your power requirements, then pick a suitable, uprated alternator and battery system.

6x55 + 1x(stereo power) + 1(sub woofer power) + 1x(amp power)+(anything else you want to run) / 12V = total current needed from lesuire battery

so depends how long you want to run all that stuff for will depend on your battery size (hours run = battery Ah / current drawn). Might need to consider 2 batteries in parallel?

might be a good idea to stick a shunt ammeter in the system, so you know how much juice your pulling and a voltmeter on your lesuire battery(s) so you know when to give em a charge, or a low batt monitor.

New, bigger alternator is a good start if its got alot of chagring to do!
 
Basically mate, split charge is a great idea.

When I finally get my act together and rewire my car I'm going to shift all my lighting, radio etc onto the second battery.

Its dead simple on a 200 shape disco so I'm looking forward to it.

But yeah basically anything you add on, power it off battery 2, then you're sorted.

All you need is a big relay, 100amp minimum (durite, about 40 quid) and switch it off the alternator.

A pair of gammatronix battery monitors is all you need really to top it off.

Happy days :)
 
lovely, cheers for he help everyone, i think il try and put a split charge in just to be safe and then an uprated alternator to go with it :)
 
According to my calculations... running 6 x 55 watt lights will flatten a battery rated at: 72 ah in a couple of hours ( i am drunk though so check the mnaths)

6 x 52 watts = 312

at 12 volts the amps drawn would be 12 * 26 amps

therefore the hours required to flatten the battery rated at 72 amp hours would be 2.5 (ish)....

Split charge... ****in right!
 
According to my calculations... running 6 x 55 watt lights will flatten a battery rated at: 72 ah in a couple of hours ( i am drunk though so check the mnaths)

6 x 52 watts = 312

at 12 volts the amps drawn would be 12 * 26 amps

therefore the hours required to flatten the battery rated at 72 amp hours would be 2.5 (ish)....

Split charge... ****in right!

only if yu are sitting with all the lights on and no engine. Bit of a dumb thing to do?

mind yu - number of chavs we used to get in Halfrauds over the winter, complaining that their 72Ah battery goes flat in a couple of days, when they were sitting up at KFC for 4 hours a nite putting out a 3KW Amp :doh:
 
only if yu are sitting with all the lights on and no engine. Bit of a dumb thing to do?

mind yu - number of chavs we used to get in Halfrauds over the winter, complaining that their 72Ah battery goes flat in a couple of days, when they were sitting up at KFC for 4 hours a nite putting out a 3KW Amp :doh:

I have a 600w amp and 500w Sub, but very rarely crank it up really high (due to excessive vibration of the panels :biggrin1:) I'm suprised that little chav egg boxes can actually power 3000w's :D :D :D
 
I have a 600w amp and 500w Sub, but very rarely crank it up really high (due to excessive vibration of the panels :biggrin1:) I'm suprised that little chav egg boxes can actually power 3000w's :D :D :D
I am not certain but I believe that you may find that the oberall consumption of the amp is not reduced simply by turning the volume down.

The volume control on older amplifiers was simply a variable resistor. This the power was being drawn but the resistor simply altered the amount of signal chanelled out to the speakers.

Hence a 3KW amplifier will consume that no matter what volume it is used at.

At least that is my understanding.
 
I am not certain but I believe that you may find that the oberall consumption of the amp is not reduced simply by turning the volume down.

The volume control on older amplifiers was simply a variable resistor. This the power was being drawn but the resistor simply altered the amount of signal chanelled out to the speakers.

Hence a 3KW amplifier will consume that no matter what volume it is used at.

At least that is my understanding.

Hmm :confused2: Thats definitely worth looking into, only thing I will say is that when the amplifier goes on with the stereo, I find that the battery charges as it does normally, so basically I thought that when the bass was cranked up, that when more power is drawn :confused: Also my amp is 600W max, and the sub is 500W max, so basically that is the max amount of power it can draw, continuous rms power on my sub is 50-250W and the amp 200W lol Definitely got me thinking though :D Atleast it isn't 3000W :D :eek:

http://www.crutchfield.com/S-SXdxZ2OsrfR/p_500SWE1042/Alpine-SWE-1042.html

http://www.kenwood-electronics.co.uk/products/car/amplifiers/KAC-6104D/
 
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I am not certain but I believe that you may find that the oberall consumption of the amp is not reduced simply by turning the volume down.

The volume control on older amplifiers was simply a variable resistor. This the power was being drawn but the resistor simply altered the amount of signal chanelled out to the speakers.

Hence a 3KW amplifier will consume that no matter what volume it is used at.

At least that is my understanding.

The variable resistor is on the input to the amplifier so turning it up makes the amplifier consume more current. All amplifiers will consume some current when idling and will consume more when the volume increases - power output will also be smaller than power input as amplifiers are not terribly efficient. On the other side, you're not getting the full output of the amp unless you're running it flat out with relatively simple waveforms, full volume sine waves can get pretty boring. And take the stated power output with a pinch of salt. A hundred watt "PMP" rated amp may only manage a few tens of watts (or less) running continuously. Even the RMS ratings can be misleading and the amp may be producing large amounts of distortion at these levels - some amps cannot produce this level continuously without overheating. So it's not always easy to estimate how much power an amplifier actually consumes........
 
The variable resistor is on the input to the amplifier so turning it up makes the amplifier consume more current. All amplifiers will consume some current when idling and will consume more when the volume increases - power output will also be smaller than power input as amplifiers are not terribly efficient. On the other side, you're not getting the full output of the amp unless you're running it flat out with relatively simple waveforms, full volume sine waves can get pretty boring. And take the stated power output with a pinch of salt. A hundred watt "PMP" rated amp may only manage a few tens of watts (or less) running continuously. Even the RMS ratings can be misleading and the amp may be producing large amounts of distortion at these levels - some amps cannot produce this level continuously without overheating. So it's not always easy to estimate how much power an amplifier actually consumes........

I stand corrected:D
 
The variable resistor is on the input to the amplifier so turning it up makes the amplifier consume more current. All amplifiers will consume some current when idling and will consume more when the volume increases - power output will also be smaller than power input as amplifiers are not terribly efficient. On the other side, you're not getting the full output of the amp unless you're running it flat out with relatively simple waveforms, full volume sine waves can get pretty boring. And take the stated power output with a pinch of salt. A hundred watt "PMP" rated amp may only manage a few tens of watts (or less) running continuously. Even the RMS ratings can be misleading and the amp may be producing large amounts of distortion at these levels - some amps cannot produce this level continuously without overheating. So it's not always easy to estimate how much power an amplifier actually consumes........

The built in fuses normally give some sort of idea although they are overspecced aswell.
 
You could always try feeding the amp via a large hot wire ammeter (someone here must have one in the back of the shed they could lend you) while playing your favourite music at various volumes. It'll give you an average current and smooth out any short term current variations.
 
most modern amps have good efficiency anyway: around 80-95%, the rest is lost as heat in the active components or powering fancy controllers in the amp.

you could get yourself a clamp ammeter, hook it round the battery + lead and turn on the sound system, play a few tracks and see what the readings are, says, 3 times every track and take an average.

then just: P=IV gives you juice your using roughly when banging out some tunes and a level your confortable with.

Me in-laws bought a rangey from some guy who "pimpped" it out with high power amp and sub-woofer, complained the battery always went flat.....not surprising really when he'd hooked the amp DIRECTLY TO THE BATTERY!:doh:
 

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