Trigger voltage for 7D and Rebel T4i

[A1original]

I'm curious if anyone knows what the 7D and Rebel T4i trigger voltage maximum are. I have a older Sunpack 422D with a dedicated Canon module, from a Canon A1, on it and was wondering if it can be used on either of these cameras. I would be using this in manual mode only.

Thanks

[cicopo]

Based on having used a Vivitar 3900 & it's dedicated module (from my A 1 days) when I first switched to digital you shouldn't have any problems shooting in manual. In fact I regret selling that flash & would still be using it in really large rooms. 

[A1original]

Thanks cicopo, I am just a little hesitant not knowing the voltage. Do not want to fry the cameras.

[A1original]

cicopo, I just checked the trigger voltage and it measures 5.5v, so I gave it a try on the 4Ti and it works great in manual mode.
Thanks for the info.

[amfoto1]

I believe both 7D and T4i will tolerate up to 250V trigger voltage.

Some older Canon models were as low as 6V.

At some point it was changed. I'm just not sure with what models that occured, but am certain the 7D and T4i have the higher rating.

You don't have a problem, either way. It sounds as if the flash you've got is a fairly modern one. Some older Vivtars,Sunpaks, etc. had really high trigger voltages... some were upwards of 400V, but even most older flashes come in below the 250V that's now become somewhat of a standard for DSLRs.  (Although I believe I've read that 24V or 36V, or something in that range, was now a rather universal minimum for all cameras that can use external flash.)

If in doubt, there are always devices to protect from excessive voltage, such as Wein Safe Sync.... Of wireless triggers.

***********
Alan Myers

San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & PRINTROOM