Question about Sunpak Auto 555 TTL Flash

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Sunpak 555 keeps flashing on it's own

I took out my 555, put fresh batteries in it, turned it on, let it charge up, connected it to a camera, started taking a few test flashes (by the trigger button, and then using the TTL synch cord, and after a few minutes it started triggering non-stop. I turned it off, waited a couple of minutes turned it back on, and it started doing it again. I've never used it with an A/C cord, only batteries, Any ideas what might be causing it or if it is cost effective to repair?

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Re: Sunpak 555 keeps flashing on it's own

Test button pins shorted to ground.

Could also be center pin shorted to ground.

Posted on Jan 20, 2008

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I need a operating manual for Sunpak Auto Thyristor G4500DX Flash gun only

I found this for a Sunpak flash which is similar to the G4500dx:

Reading from the "auto555/G4500DX" Manual, you need to:
1. Slide the Film Selector to desired ISO - (that is the same as your camera ISO used - so, make sure you turn Off the Auto ISO feature if your camera has one).
2. Slide the Mode Selector to "A" (Auto position). This will be Auto Thyristor mode on the flash.
3. Slide the Auto F/stop Selecct Know to desired lens openning - ( so use your camera in Aperture priority mode, more in Manual to prevent changes in the camera aperture value during shooting)
Shoot, and be happy with well exposed pictures by the Auto Thyristor features of the Sunpak 555 flash.
The Sunpak 555 works great with Nikon D50, D70 cameras, as you can synchrinize flash practically at all shutter speeds. Excellent for sunny days to get narrow DOF, yet get any ambient light level contribution as desired.
For other cameras, make sure (watch out for) that Aperture Priority mode does not use shutter faster than the camera max X-sync speed - so Manual camera mode could be a better choice for a novice photographer.
In the manual there is also a list of accessories for various brand cameras, How to use Power Ratio in Manual mode, some advice on using wide lenses, how to care of your 555, and Specification section.
Minimal flash duration is 1/450 at full power, so you can safely use Auto Aperture up to 1/500 sec. Flash duration decreases with lower power setting, or lower auto mode need for poser, and the shortest flash duration is 1/17000th sec.

Jan 29, 2016 | Sunpak Camera Flashes

1 Answer

How long do i charge a sunpak nc 510 rechargeable using a QBC-5 CHARGER

Sunpak uses different power sources on their high-power handle mount (a.k.a. hammerhead) flash guns. The most common is the battery basket that holds 4 or 6 AA or C batteries depending on the type of the unit. One can insert Nickel-Cadmium or Nickel-Metal-Hydride rechargeable batteries instead of the primary cells, this way reducing the "consumables" costs at the expense of the smaller number of flashes per battery set. (Actually, NiCd or NiMH cells would probably give smaller number of flashes compared with the alkaline cells, but the recycle time between the flashes can be shorter. The reason is that at charging the flash capacitor inside the flash current counts more than voltage. Sunpak sells Ni-Cd battery packs named CL-2 for their flashes that utilize 6 AA-cells, and CL-3 for their 622 series (4 C-cells). The charger for these is the QBC-5. It recharges the exhausted batteries in 3 hours. As a solution assuring the shortest duration between flashes Sunpak offered the Powerpak, a shoulder holster that held a dry (non-rechargeable) battery of 510V, it charged the flash capacitor directly, omitting the transistor inverter in the flash body. As such battery became obsolete, the Poverpak has been superseded with the NC510 and later the TR-II PAK, which utilizes 10 Ni-Cd rechargeable batteries as a power source, and a powerful (more capable than the one in the flash) transistor inverter. NC510 and TR-II PAK use the same connection to the flash and the same outlook as the original Powerpak but, being rechargeable, are more economical. QBC-5 also serves a charger for the NC510 and TR-II PAK. You may ask, how the same charger can be used for 4, 6 and 10 cell NiCd packs. Well, the charger is specially designed for that, although charging time differs at the different battery packs. The NC510 and the TR-II PAK needs 10 hours to be recharged, when exhausted. The best way to avoid damages (overcharging degrades NiCd and NiMH cells) is to check temperature of the batteries. Charging must be cut off if the battery becomes hotter than 45 ?C (115 ?F). If after 10 hours of charge the NC510 does not power (the otherwise working) flash, then it must be serviced. Replacing the batteries is an easy job that can be done at home, with some soldering skills; NiMH cells with solder tabs are available at many web-based supplyers. Don't solder the cells directly, heat damages them. Avoid touching parts inside, when the pack is turned on: electrocuting is fully possible. Better find a professional, if you are not familiar with the electronics.

Jan 08, 2014 | Sunpak Camera Flashes

1 Answer

Is a canon rebekt2i compadable with a sunpak555

The trigger voltage is a bit on the high side. According to this list, it's "your call." If you want to be absolutely safe, use something like the Wein Safe-Sync.

Jan 29, 2013 | Sunpak Auto 555 TTL Flash

1 Answer

Using a Sunpak 555 with Cybersync transmitters with a canon 40D off camera and getting inconsistent firing

did you find a solution? ive experienced a similiar problem. i think i might need to buy new flashes.

Aug 13, 2012 | Sunpak Auto 555 TTL Flash

1 Answer

How does the Sunpak Auto 555 Thyristor Flash Unit work concrning a battery? Does it always need the ourside battery pack unit also?

When internal cells are fully charged it do not need external ones

Aug 07, 2010 | Sunpak Auto 555 TTL Flash

1 Answer

How can you connect a Sunpak 555 to a Nikon D2x?

You will need a Sunpak's PC Sync cord to Nikon D2x's PC socket.

Dec 15, 2009 | Sunpak Auto 555 TTL Flash

1 Answer

Won't flash when connected to my Nikon D80???

Set the settings to TTL for both the camera and the flash

Jun 27, 2009 | Sunpak Auto 555 TTL Flash

1 Answer

Canon Macro Settings for 100mm lens and Sunpak 12R ring flash

Firstly, be sure to check flash voltage. Your 30D may accept max 6V so that your camera can be shot if the flash unit has higher voltage than 6V.
1. Use low ISO to keep low noise....around f/8 or more depends on your need and how much DOF you want.....Set the shutter speed around 1/125 to your max speed to stop any movement (your subject or camera itself shaking).
2. Above is set in Manual mode (iso100, f/8 1/125 or 1/250), then you just need to leave the flash to work in TTL mode.
3. It needs battery, the connection is for syncing to trigger and release a proper flash power (in TTL mode).
Hope this help!

Mar 26, 2009 | Sunpak DX-8R TTL Ring Light Flash

1 Answer

Sunpack 555 inconsistantly fires with Pentax K20

Your strobe is faulty and needs repair at a trained service center. The actual culprit may be the voltage converter circuit that supplies the high voltage to the flash capacitor, or the voltage divider that drives the ready lamp and, at the same time, makes triggering possible.

Feb 16, 2009 | Sunpak Auto 555 TTL Flash

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