Power Ratio Plugs

[Neal Shields]

I purchased an estate sale Photogenic 500ws power pack model AA01. It looks "rode hard and put up wet". but will fire a strobe on all outlets.

However, it is missing the "power ratio plug" The socket for this plug looks like an 11 pin vacuum tube socket and sets the flash ratio between the heads. (Photogenic listed 10 or 15 different ones for all possiable combinations.)

One of the problems with getting wonderful deals, is that it will just about double my investment to buy a even a single plug.

Does anyone know if the unit defaults to full power or min power without the plug or where I can find wireing diagrams on the net to make my own.?

I found some blank plug for 25 cents each at an electronics surplus store so if I had wireing diagrams, I would just need some resistors, jumpers and solder and I suspect I would be set.

Thanks

Neal

[Mark Sampson]

I used these packs when I worked as a high-school senior-portrait photographer for a large studio, about 25 years ago. They were ok for that application, where the lighting was not supposed to change. There were no flash meters, exposure was set by test and the main light (and the 3 others) were positioned at the same distance everey time. As I recall it was about 400w/s, so the exposure for VPS II was around f/11 and 1/3. It's probably worth buying a plug from Photogenic. They did work well but I had one or two blow up over the two years I held that job...

[John Cook]

Neal, this sounds like a question best answered by the factory service guys.

You are aware that potentially fatal electrical capacitance can build up in these units even unplugged, sitting on the shelf? Horsing around with a power pack calls for extreme alertness.

As a former military electronics technician, my advice can be construed as “your tax dollars at work”. I was once flown to Alaska as an emergency replacement for a technician who had been electrocuted by a large capacitor in storage.

However, as to the matter of the pack defaulting to full power or minimum power without a plug, I would guess it is most likely full power.

These plugs sound like some sort of dummy load used to drain power away from another flash head outlet wired in tandem with that one holding the plug.

As I’m sure you know, a common method for controlling flash head power is to “dump a head”. This is done by plugging a second head into a common outlet, thereby dividing the full pack power available to half power for each head.

The “dump” head is then pointed away from the photographic subject to dump its light elsewhere. Light intensity on the subject is then reduced by one stop.

[Neal Shields]

I have asked the factory but they have not replyed yet.

If I was them I wouldn't be giving me information that I could use to electrocute myself, so I am not holding my breath for an answer on how to wire my own plug up.

Thanks for the other two replys they are very helpful.

Neal