Imac early 2009 firewire 800 port voltage ???

Question

Hi all,
Have several Imac intel core duo's 2.66ghz SN: VM933RUD0TH or early 2009
Having searched and searched and searched for the voltage output for the firewire 800 connector. I cannot find any information at all.
The Apple official Tech Spec tells me that it is 7 watts but does not give me any amp rating at buss level, so am unable to calculate without having to do a manual test..
All other sites tell me that standard 800 fw output should be somewhere between 24 volts>30 volts
We have a 20k piece of kit that needs 12v supply through firewire and it keeps chugging and dying when it is connected to the Imac so am thinking that it isne supplying a full standard current and Apple are cleverly disguising it with 7watt on the tech spec.

Answer 1

yes this is the problem I am finding, phase one offers a repeater that can multiply the length of cable from 5m to 10m (yippee) @ an additional cost of £800 (second yippee).
Was trying to find one from alt company but the techy info seems to be a bit thin on the ground from companies that provide this and the prices seem to be skyward - so purchasing them to test the devices becomes prohibitive.
Phase's work around for laptops + low volt supply is as follows:
The p30+ and upwards have the ability to force battery power, so that when shooting tethered it pushes additional volts+amps down the line. Once again this is restricted to a 4.5m cable which when shooting tethered is a pain in the proverbial, also eats batt power (additional batts cost £60 each)
And if you get the configuration wrong in the menu (as our multiple user environment has evidenced) it it kills the batts and the camera..... (we just sent it off for repair hence these posts and research into it)
I just think that it is a bit of a pain when working with two pieces of kit, which allegedly use universal and standard connections to find that the universality and the standardization is not really there.
(new I should have gone for a HBlad)