Wednesday, 18 November 2015

Testing the V2-F1A with an old high trigger voltage flash

One of my buyers complained about that the adapter he bought was not working, the camera simply not triggered the flash, nothing happened. He tried with another flash unit and the results were the same. The flash units were ProMaster FT 1700.

I don't have that flash so I can't test the same model but I immediately suspected that there must be something wrong with that flash model. It is not easy to find out data about that flash but eventually I found that most Internet evidence states that the flash has high trigger voltage. Of course, I immediately warned the user of V2-F1A about what I found out and asked him to measure the trigger voltage if he can and that he should test the camera and NEVER to use those flashes again until we know what happened. He confirmed that his camera was still working but never actually confirmed the trigger voltage. Never the less, I am certain that based on his fault description and the information found on the Internet the “problem” is isolated to that flash model and to the fact that it has indeed high trigger voltage.

The “problem” isn’t really a problem

The same evening I made some tests with one of my own old flashes with high trigger voltage. My tests resulted in confirmation of the same behavior he experienced, which is that when the adapter is attached to the flash the flash will not fire. I made some measurements and documented the results in a short video which I sent him the same evening.

Watch the short video above to see what is going on


This short video is made for demonstration only. The flash is not tested on the Nikon 1 V1 camera and I will not do that because I don't want to risk my camera. You should NEVER try this with your own V2-F1A, and absolutely never when the adapter is on the camera. There is a protection diode built in, but there is no warranty that it works with every flash every time.


The protection diode does what it is expected to do, i.e. protecting your camera from the high voltage. Without the diode his camera would have been destroyed by now.

Lessons YOU should have learned

There is an even more important conclusion, which is: Read the manual. The adapter is delivered with a short but clear manual stating NEVER to use the adapter with unknown flashes and that it is designed to be used with low trigger voltage flashes. Of course, you don’t have to buy the adapter to find that out, I never made a secret about this. This information and warning can be found all over this blog also, but the two most important posts are:

Worth repeating over and over again

I don’t know how many times this should be repeated, but because there is no information about the maximum possible trigger voltage the Nikon 1 cameras can handle the protection diode is necessary to protect the camera from getting destroyed when users ignore all information and go against common sense, trying to use just about any unknown flashes. If you do that, you do that on your own risk. There is a protection diode but how many times it can handle the high voltage is nothing I can answer.

The technical behavior of a Zener diode

When a Zener diode works normally it will clip the voltage at the level it is designed for. The diode in the V2 is a 33V diode, meaning that it will not allow voltages over 33V to pass through, this behavior can be seen in the video above.

When a Zener diode is exposed to very high voltage (a few thousand volts) the semiconductor in the diode becomes a conductor and will short circuit its terminals. If that happens then the V2-F1A becomes completely useless. Eventually the same thing will happen if the diode is exposed to high voltage in the lower range (few hundred volts) many times. There is no way to tell how many times you can abuse a diode, but sooner or later it will burn up. It can also result in the semiconductor burning up completely and in that case the protection diode won’t do any more protection, just like if it was not there at all. You can measure the existence and the health of the protection diode if you have the right knowledge but a normal user will not notice the absence of it unless he attaches a high voltage flash and tries to use it on your Nikon 1 camera.

Of course, it may result in a destroyed camera, but because I will never try this I don’t know and not sure if the camera can handle it without the diode.

Final words

The V2-F1A shall only be used with flashes designed to be used on digital cameras. Any other use is at your own risk. The adapter is NOT working with a high trigger voltage flash if the V2-F1A is fully functional. Don’t try this out, it is better to find out the trigger voltage before buying the adapter or buy a flash which is known to be having low trigger voltage.