Overloading the alternator

[spandit]

After some theory here... from what I remember, the alternator as fitted to Pinzgauer's is capable of supplying 35A. At 24V this is 840W of power (P=VI)

The headlights themselves are 75W, I think, so that's 150W gone (giving us 690W left to play with - bear in mind, I haven't taken the power needed to run the ignition system, rear & interior lights etc.)

If I were to fit spotlights that exceeded this power would it damage the alternator to switch them on or would it just start draining the batteries which could then be recharged later? I'd be using them for short periods only...

Just shooting the breeze (whilst I wait for my new spotlight bar to arrive), would be interested to hear the response

[Picasso]

Yes it would just start to drain the batts. With LED lights so cheap I wouldn't worry about it, unless you got some big halogen spot lights.

[spandit]

It's for running spotlights. Can someone tell answer me this:

Is a 24V 70W bulb brighter than a 12V 55W one? I've bought a spotlight bar and 4xHella FF50 spotlights, that take H7 bulbs. A standard 24V bulb is 70W (which wouldn't overload the alternator if I had 6 going at once - 2 headlights and 4 spotlights) but with 12V bulbs being so much cheaper I'm wondering about fitting them in pairs with 100W bulbs. I understand that if one bulb blows you lose them both.

Basically, do 2x100W 12V bulbs in series consume the same as 1x100W 24V bulb? P=VI seems to suggest that they would but I've been wrong before

[milesdzyn]

Why not go with a H7 24 volt 35 watt HID conversion kit. They're very bright and fairly reasonable now. Look at how often your going to be using your spots, they probably won't burnout from use and running 35 watts bulbs will save you from damaging your Alternator which isn't cheap to repair or replace.

Just Google - H7 24 volt 35 watt HID

Miles

[spandit]

It's a possibility, I suppose but extra hassle in wiring/installing the ballasts & still 10x the price of regular bulbs. Take your point about the alternator but even 400W of spotlights would only pull 17A.

[edzz]

It's for running spotlights. Can someone tell answer me this:

Is a 24V 70W bulb brighter than a 12V 55W one?

A 70 watt bulb will be brighter than a 55 watt bulb of same design and quality.

Basically, do 2x100W 12V bulbs in series consume the same as 1x100W 24V bulb? P=VI seems to suggest that they would but I've been wrong before

No two 100 watt bulbs equal a 200 watt load, in parallel or in series same thing 200 watts are 200 watts. Wattage is a way of expressing power usage without needing to know the voltage or amperage of a device. http://en.wikipedia.org/wiki/Electric_power

[spandit]

Thanks, Ed, I'll probably stick to 24V bulbs as at least it makes it easier to assess which one has blown!

[Mickey]

Why not go with a H7 24 volt 35 watt HID conversion kit. They're very bright and fairly reasonable now. Look at how often your going to be using your spots, they probably won't burnout from use and running 35 watts bulbs will save you from damaging your Alternator which isn't cheap to repair or replace.

Just Google - H7 24 volt 35 watt HID

Miles

I appreciate you. I have installed H7 35w hid kit. It is %300 brighter than halogen bulb.

[waterdog]

never question that one myself !!

[audiocontr]

You may need to locate a jeep to roll you back over.

[TechMOGogy]

You may need to locate a jeep to roll you back over.

[audiocontr]

looks like he fixed the picture... It was originally upside down.

[waterdog]

found a jeep nearby

[audiocontr]

Just noticed something interesting. View this thread on a PC and the photo is right side up. View it on an iPhone and its upside down.

[pcolette]

Photo is right side up on my Mac. Strange...