----- Original Message -----
Sent: Monday, December 19, 2005
10:21
Subject: [PSUBS-MAILIST] o2 control
brian
the sensors that you are
looking for are teledyne analytical instruments
class r-22d, o2 sensors. they put out a milli
volt singal directly perporsional to the amount of o2 present the
average output is 7-13 mv in air at stp. the need to be loaded with a
10k resister. Measure the output with a milli volt meterany kind will do.
if the voltage drops ten percent you know that your o2 levels droped ten
percent.
o2 control can be done three
ways.
1.o2 level monitoring with a
solinoid for injection
pros hands
off automatic control
cons
expensive and complex
2. automatic pressure
controller maintain sub internal pressure to a fixed
point
pro single
controller all mechaincal/ about half price of electrical
con
compressed air leak internal inside sub will shut down
system
3. adjustable flow controller
manual
pro
cheapest
con
requires continous monitoring
hope that this helped for your design
ideas
rick m