[VAC] Re: Control panel tank levels

[John Leggett <pklhead2@xxxxxxxxx>]

Jim-
In the schematic, the collector side of each
transistor is connected to the lamp which in turn is
connected to the (hot) panel switch.  The emitter side
is run to ground, and the base control leg is
connected to each probe wire to activate the
transistor-switch and allow the lamp circuit to go to
ground.  

There is a 1k ohm resistor shown in the line running
from the switch to the hot 4th wire going to the
probe.  This is the only resistor I see.  Is this the
one you're referring to?

As described in an earlier response, when operating
properly I think all lights should illuminate when the
tank is full, since all probe wires are submerged. 
They will go out as each becomes exposed as the tank
level recedes.  So the lights act kinda like a poor
man's bar graph indicator.

My problem continues to be that all the water tank
lights light up all the time, whether they are exposed
or submerged.  With the holding tank sensor, I get a
weak red light when the probe is dry but a strong
yellow and strong red when they are both submerged.

I'm about out of ideas at this point as to what to try
next.

John 
68 Safari