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Damian Aimers
09-09-2014, 8:53pm
Hi team, I am unsure if anyone has done this or if it works but has anyone used their studio lights with a battery pack that is designed to jump start cars?

I was looking at getting some portable strobes but if this would work I could just get the pack and make my strobes portable?

In theory.

So has anyone been crazy enough to give it a go or get it working or have a better idea?
I am looking into it now but if anyone has done so it could save me time and lots of money.

feedback appreciated

MissionMan
09-09-2014, 9:08pm
If you get a power pack with a plug point it may be possible, but I couldn't vouch for how well they would work and the risk of damaging your lights.


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arthurking83
11-09-2014, 4:22pm
So you currently have 240v studio lights, and to your aim is to have a portable power pack to use them away from a 240v source.

if you have access to a 12v power source(whether a bare car battery, or vehicle, or one of these battery jumper devices, you still need a power inverter to convert the 12v source to a 240v supply(for the studio lights)
For this you need an inverter.

Unless you specify the specs of the studio lights, we can't offer any advice as to what inverter is required as a minimum.

But be warned .. that high powered 12v to 240v inverters are not cheap.

as an example, if your studio lights are 150Watt and you have two that you want to power, then you need as a minimum a 300W inverter(150x2). But it's safer to have a bit of headroom in the inverter and get one with some in reserve. So a 450W inverter will provide a more reliable supply to the studio lights.

Problem is, that such a high powered inverter on a small battery source will drain the battery in no time at all. Those car jump starter devices don't have all that much capacity reserve in their batteries.
They are designed more as a convenience tool, rather than as a real battery source. A typical medium car battery has much more capacity as a power supply.
The easiest way to gauge the power capacity of the battery is via it's weight. Heavier usually means more.
The specs of the battery that will be important to look for are it's Ah(amp hour) rating RC(reserve capacity). Again, more is better.
CCA ratings are probably not as important as you won't be loading the battery up with huge power drain(50 amps) for any length of time ... such as a car starter.

if our 300W studio light scenario is accurate, then the available time with a 450W inverter and a std Commodore type car battery say 100Ah rating will something like this.

300W / 12v (ie. load on car battery as the lights are in use) = 25 amps.

100Ah rate for the battery is based on a lower current load than this. Something like 10A over a 10 hour period(can't remember exactly some batteries(deep cycle) have a different Ah rating.
But as you put more load on the battery(ie. 25A compared to 10A) the battery discharges more quickly. Think of it as the difference between trying to start the car for 10mins, compared to leaving the headlights on all day. The headlights use less current, so not only last longer overall, but last longer in terms of power used too.
So you may get 10mins with the starter motor, but 10 hours with the headlights.

So in theory your 2 150W studio lights may last you about 10 .. maybe 20 mins in total. That's with a standard (commodore type) battery. I estimate that a typical jump starter pack probably has about a 10 0r 20Ah rated battery .. smaller and lighter for ease of use and packaging .. probably just enough to start a car with a flat battery in one or two attempts .. but not for 10mins like the car's battery would.

The numbers aren't exact figures .. just guidelines to give you an idea of how it all works.

Damian Aimers
19-09-2014, 11:40am
Mate, brilliant information. The technical sides of this I had no idea abort... Until moments ago (where I read this, your reply).
You have just saved me a lot of precious time and money. I think I will leave the cowboy idea on this one and grab the real Macoy.
Thank you

feral1
18-11-2014, 4:28pm
I Tried a 300watt inverter for one of my 240 volt light, it did not work at all. I think you will need nothing under 1000 watt inverter. I have not tried this as yet. But I do not even bother. I have 2 flash heads and 3 remote triggers that allow 1/8000 sinc.

Peter