Magnitude of trigger voltage in xenon flash tubes?

[grizedale]

hello,

with xenon flash tubes of 1W to 5W power range, what are the dangers of ...

1...too high trigger electrode voltage
2....too low trigger electrode voltage.

Also, given the effort needed to design a low power xenon flash tube lamp................is the hardest part of the overall job in tuning the trigger voltage?.....ie ensuring that you always have exactly the right trigger voltage?

..ie too much and you burn out the trigger transformer and get noise in the circuitry, too low and you never trigger

 

[FvM]

too much and you burn out the trigger transformer and get noise in the circuitry, too low and you never trigger

I think, this is the complete answer to Q1 + Q2. There's a certain range however. A standard trigger transformer like Heimann ZS1052 will work with "1 - 5 W" flash tubes at the nominal primary voltage of 300 VDC.

This is a good starting point for regular designer craftsmanship, you don't need to to undertake a research project to proceed.

 

[grizedale]

Thanks, but supposing i trigger the tube with say 3KV, and then i change the trigger circuit to make it trigger at 5KV......would the tube being triggered at 5KV consume more power?

 

[FvM]

The tube power consumption is set by the flash capacitor energy (capacitance+voltage).

 

[grizedale]

-but surely with the lesser trigger voltage, the ionisation of the xenon gas is incomplete, and the xenon tube will not flash over with as much energy,

-i mean, thinking if it like this, supposing i repeatedly reduce the trigger voltage........then surely at some point, the lamp will trigger but it will not be a very energetic breakover and the tube capacitor will not be discharged very much.....?

 

[FvM]

I never experienced a behavior as supposed. I think, it would contradict the nature of an arc discharge. The discharge is either triggered, then gas ionization rises avalanche-wise or it's not triggered. Up to a certain degree, the current rise time and plasma shape may be influenced by the trigger energy and and trigger electrode geometry.