Flash trigger voltage

[paul139]

Hello all.
I’m considering buying a Godox Lux Senior flash to use with a few different film cameras that I own ( SLRs , Medium format, folders etc )
I’ve contacted Godox and asked about the trigger voltage and they replied with this info below.
Would anyone know if this is in the safe voltage range for older cameras?
Thanks.

 

[Sangoma]

Hello all.
I’m considering buying a Godox Lux Senior flash to use with a few different film cameras that I own ( SLRs , Medium format, folders etc )
I’ve contacted Godox and asked about the trigger voltage and they replied with this info below.
Would anyone know if this is in the safe voltage range for older cameras?
Thanks.

The unsafe thing is old flashes with new cameras.
If the old cameras have little electronics in them, the voltage doesn't usually matter as the flash switches were mechanical.

New cameras on the whole should not be used with trigger voltages higher than 5V, though I believe EU regs said more, think they are supposed to be able to withstand about 28V without damage, but I would never use a flahe with a trigger voltage that high on a new camera.

Many film camera flashes had trigger voltages of 200V up, which could easily spell the end of a modern camera

It does also depend on what you describe as an old or modern camera.

Those specs don't seem to give the trigger voltage, but it is very easy to measure.

 

[paul139]

The unsafe thing is old flashes with new cameras.
If the old cameras have little electronics in them, the voltage doesn't usually matter as the flash switches were mechanical.

New cameras on the whole should not be used with trigger voltages higher than 5V, though I believe EU regs said more, think they are supposed to be able to withstand about 28V without damage, but I would never use a flahe with a trigger voltage that high on a new camera.

Many film camera flashes had trigger voltages of 200V up, which could easily spell the end of a modern camera

It does also depend on what you describe as an old or modern camera.

Those specs don't seem to give the trigger voltage, but it is very easy to measure.

Thanks for the reply.
The cameras I would use it on would be some Contax’s, so full of electronics but I would also use with a Rolliecord vb, Bronica etrsi, Mamiya C330 and a Leica 111f as well maybe even a Leica R8 so again full of electronics.

 

[jknights]

You might find this table useful.

Photo Strobe Trigger Voltages

 

[Sangoma]

Thanks for the reply.
The cameras I would use it on would be some Contax’s, so full of electronics but I would also use with a Rolliecord vb, Bronica etrsi, Mamiya C330 and a Leica 111f as well maybe even a Leica R8 so again full of electronics.

It's very easy to measure the trigger voltage, however if the flash is designed for dSLR cameras, it is likely to be low, and not too high for older cameras.
As that spec sheet does not give the trigger voltage, you will need to measure it to be sure.

I see it has a lithium battery, so I guess it must be quite modern.

I don't know how any of those cameras trigger the flash, so no idea of their limitations on voltage, though that may be given in their specs.

 

[jknights]

If in doubt then one of these used in between the flash sync cable and the socket is a safe method.

https://www.bhphotovideo.com/c/product/245292-REG/Wein_W990560_Safe_Sync_Hot_Shoe_to.html?gclid=EAIaIQobChMI8ujDj5es_AIVUdDtCh0z9gcnEAQYASABEgIAJPD_BwE

I got my one in UK on ebay.co.uk

 

[G.K.Jnr.]

This may help you if you want to measure a flash trigger voltage.


Flash Trigger Voltage.

Trigger voltage is measured between centre pin and edge contact on the flash's hot-foot.

To check an unknown trigger voltage, you'll need a digital multimeter. For most reliable result, the input impedance of the meter should be 10 mohm, or higher.

To measure, put fresh batteries in the flash you want to check, and charge the flash until the “ready” lamp (or equivalent) is lit. Then set the range selector on the meter to the most sensitive DC range. To find the right range, start with the highest DC range and go downwards until the meter indicates you are out of range. Then back up one step. This is the most sensitive range. You should now be able to read the flash's trigger voltage from the meter's display.

You meter the voltage between the centre pin and the edge contact. If there is more than one pin below the flash, it is the centre one you're interested in. It will make contact with the large round contact in the centre of the camera's hot-shoe. The edge contact may be a small metal square recessed in the hot-foot, or something larger. It is designed to make contact with the metal of the mounting bar on the edge of the camera's hot-shoe. You always connect the negative probe (black on most meters) to the edge contact, and then connect the positive probe (red on most meters) to the centre pin.

Measuring voltage with a digital multimeter. Black probe on edge contact, red probe on centre pin.

Prior to metering, I've set the meter to use the range 0 to 20 volts. I use my hands to connect the points of the positive and negative probes to the metal of the Speedlight's hot-foot.

Alternatively, you can measure the voltage between the centre (+) and edge (-) of the pc-socket.

Note that older analog voltmeters may have a low input impedance which may result in a voltage drop inside the meter. This will result in a too low reading. For best results, use a digital meter with a impedance of 10 mohm or more.

Sometimes, the gap between the foot of the flash and the screw for fixing it in the hot-shoe may be too narrow for the meter's probe to reach the metal of the edge contact. If the flash has a pc-socket, you can alternatively measure the trigger voltage from the pc-socket.

You connect the negative probe (black on most meters) to the edge, and the positive (red on most meters) to the centre of the pc-socket.

In addition to the trigger voltage, the polarity of the flash is important. All modern cameras expects the centre pin of the flash to be positive and the edge contact to be negative.

If things are the other way around (reverse polarity), even a very low voltage may cause harm. If the unit has reverse polarity, you will see this by the voltage displayed as a negative number (a minus-sign is placed in front) on the display of a digital multimeter. Never use a flash with reverse polarity on a modern camera!

 

[paul139]

It's very easy to measure the trigger voltage, however if the flash is designed for dSLR cameras, it is likely to be low, and not too high for older cameras.
As that spec sheet does not give the trigger voltage, you will need to measure it to be sure.

I see it has a lithium battery, so I guess it must be quite modern.

I don't know how any of those cameras trigger the flash, so no idea of their limitations on voltage, though that may be given in their specs.

Yes it is a relatively new flash and can be used via hotshot or pc socket.

 

[paul139]

If in doubt then one of these used in between the flash sync cable and the socket is a safe method.

https://www.bhphotovideo.com/c/product/245292-REG/Wein_W990560_Safe_Sync_Hot_Shoe_to.html?gclid=EAIaIQobChMI8ujDj5es_AIVUdDtCh0z9gcnEAQYASABEgIAJPD_BwE

I got my one in UK on ebay.co.uk

Thanks.

 

[paul139]

This may help you if you want to measure a flash trigger voltage.


Flash Trigger Voltage.

Trigger voltage is measured between centre pin and edge contact on the flash's hot-foot.

To check an unknown trigger voltage, you'll need a digital multimeter. For most reliable result, the input impedance of the meter should be 10 mohm, or higher.

To measure, put fresh batteries in the flash you want to check, and charge the flash until the “ready” lamp (or equivalent) is lit. Then set the range selector on the meter to the most sensitive DC range. To find the right range, start with the highest DC range and go downwards until the meter indicates you are out of range. Then back up one step. This is the most sensitive range. You should now be able to read the flash's trigger voltage from the meter's display.

You meter the voltage between the centre pin and the edge contact. If there is more than one pin below the flash, it is the centre one you're interested in. It will make contact with the large round contact in the centre of the camera's hot-shoe. The edge contact may be a small metal square recessed in the hot-foot, or something larger. It is designed to make contact with the metal of the mounting bar on the edge of the camera's hot-shoe. You always connect the negative probe (black on most meters) to the edge contact, and then connect the positive probe (red on most meters) to the centre pin.

Measuring voltage with a digital multimeter. Black probe on edge contact, red probe on centre pin.

Prior to metering, I've set the meter to use the range 0 to 20 volts. I use my hands to connect the points of the positive and negative probes to the metal of the Speedlight's hot-foot.

Alternatively, you can measure the voltage between the centre (+) and edge (-) of the pc-socket.

Note that older analog voltmeters may have a low input impedance which may result in a voltage drop inside the meter. This will result in a too low reading. For best results, use a digital meter with a impedance of 10 mohm or more.

Sometimes, the gap between the foot of the flash and the screw for fixing it in the hot-shoe may be too narrow for the meter's probe to reach the metal of the edge contact. If the flash has a pc-socket, you can alternatively measure the trigger voltage from the pc-socket.

You connect the negative probe (black on most meters) to the edge, and the positive (red on most meters) to the centre of the pc-socket.

In addition to the trigger voltage, the polarity of the flash is important. All modern cameras expects the centre pin of the flash to be positive and the edge contact to be negative.

If things are the other way around (reverse polarity), even a very low voltage may cause harm. If the unit has reverse polarity, you will see this by the voltage displayed as a negative number (a minus-sign is placed in front) on the display of a digital multimeter. Never use a flash with reverse polarity on a modern camera!

Thanks for that info. I can see I need to do a bit more research.