Friday, May 1, 2020

Neon Indicators.


Fault : One one Neon in each of the three panels lit up. The actual one moved a few times. Likely only enough current was flowing to light one neon after which there wasn't sufficient current to keep the voltage above the strike voltage. I must have miscalculated the resistances erring on the high side.  I wonder if the variation in the current draw / strike voltage is such that there is a limit to the number that can be run off a single dropper resistor? Might have to break each segment into separate zones?
_______________________________________________________________________________
Recalculate : Each indicator uses 0.2 mA so at 240 - 80 = 160  volt :

4 = 24 indicators or 5mA 32 k Ohm

2 = 25

0 = 33 or 6 mA or 27 k Ohm

240 = 32

at about 1.0 watts or about 4 1/4 watt resistors... might have to mount them artfully on the circuit board to get it done. I don't want to go shopping for 3 resistors. 
_______________________________________________________________________________

Each indicator uses 0.2 mA so at 240  volt :

4 = 24 indicators or 5mA 48 k Ohm

2 = 25

0 = 33 or 6 mA or 40 k Ohm

240 = 32

at about 1.5 watts or about 8 1/4 watt resistors... might have to mount them artfully on the circuit board to get it done. I don't want to go shopping for 3 resistors.  



There will need to be a 330 Ohm resistor in the GPO where the wiring comes from as a fuse in case of a short.


No comments:

Post a Comment