You should take care to:
*) power dissipation
*) current at the operation point (all diodes must operate in the low resistance region)
*) zener impedance at the operating point
Regards
Z
4 x 75V/5W zener seems to work OK with a 12V car battery through a tv flyback transformer.
But clearly 3 x series car baterries (36V) is producing a kick back current that is exceeding the power rating of the zeners and frying them.
Possibly 2 x series car batteries (24V) is doing the same thing but perhaps frying them more slowly as 24V was operating my mosfet based jacobs ladder circuit OK, at least for the short time I have been trying it.
Any suggestions on more appropriate zener diodes than 1N5374s?
Also I have been reading that MOV varistors are often used to suppress voltage spikes. From what I have read these would be a far more robust way of doing so than zener diodes in that it would be far less sensitive to increases in the input voltage that I might like to try with my mosfet flyback transformer driver.
My research has revealed this:
Ordering code*****VRMS(V)****VDC(V)****max(8/20 μs)A****Wmax(2 ms)J****Pmax W****Vv(1 mA)V****ΔVv(1 mA)%***vc, max(ic)V**icA*****Ctyp(1 kHz)pF
B72220S0111K101**115********150******6500************60.0**********1.00*******180*********±10*********300********100.0***1520
Would this device for example be a suitable replacement for 4 x 75V/5W zener diodes?