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H20ENG
14.10.2009, 02:10
How do you all set up your Ca reactor CO2 with the Profilux? I know you all ditched them in favor of the cool dosers, but someone must still use a reactor?

Without having it open in front of me, I think I have the first probe to shut off the CO2 solenoid at low tank pH.
Second probe shuts off solenoid at low reactor pH OR low tank pH

mshur
14.10.2009, 07:03
How do you all set up your Ca reactor CO2 with the Profilux? I know you all ditched them in favor of the cool dosers, but someone must still use a reactor?

Without having it open in front of me, I think I have the first probe to shut off the CO2 solenoid at low tank pH.
Second probe shuts off solenoid at low reactor pH OR low tank pH

you only need one prob to control CA RX.
set operation mode on twoposition controler, on the control set "nominal value"-6.5, hysteresis-0.3
Under socket function set-ph value 2 decrease

mike

Chew
14.10.2009, 14:30
you only need one prob to control CA RX.
set operation mode on twoposition controler, on the control set "nominal value"-6.5, hysteresis-0.3
Under socket function set-ph value 2 decrease

mike

Yup thats exactly how mine is set up too!

H20ENG
15.10.2009, 00:43
Thanks. I realize you only need one pH probe for the reactor. I guess my question should have been more clear. When using 2 probes; one for the reactor, one for the tank, what logic do you assign the probes?

I have the reactor pH probe programmed as you mention, but the tank pH probe also turns off the reactor co2 solenoid if the tank pH gets low.

I assume if you have a reactor with a pH probe in it, you also have one in the tank itself. Just wondering what programming everyone in this situation is running:) Thanks for your time.

mshur
15.10.2009, 04:58
for Ph1 you dont use controler, so you dont need to set up socket functions.
just set nominal value

mgpro
25.11.2009, 12:50
Sorry to reopen this thread, but I'm after a similar answer and don't feel that the answers so far are complete.

I'm comfortable with using (in my case) pH3 to control the opening of the solenoid valve to release CO2 into the Calcium reactor, using the method described earlier. (this probe sits in the Ca reactor, aiming at 6.5 pH)

But I would like to be able to turn off the solenoid if my pH1 probe (measuring tank pH) goes below say 7.8. I consider this a safety backup. How can I do this?
thanks
mgpro

Matthias
26.11.2009, 08:52
use the programmable logic:

logic x:
input 1 = pH1 increase
input 2 = PH2 decrease
function AND

then assign to the socket in question the function logic x

-> only if both conditions are present the socket will be on

mgpro
26.11.2009, 10:54
Thanks so much Matthias. I've created the logic as per instructions, but I'm not sure its working the right way.

pH1 (tank) reads 8.44
pH3 (reactor) reads 8.43

On this basis the solenoid should be on, allowing CO2 into reactor to lower pH. But the socket display tells me its off (I've checked, there is no CO2 flowing). Where have I gone wrong?
mgpro

mgpro
26.11.2009, 11:48
replying to my own question here

After playing around with it I think I need both conditions to be Decrease.

ie socket on unless pH1 goes below 7.8 (nominal value 8.1, hysterisis 0.3)
socket on unless pH3 goes below 6.2 (nominal value 6.5, hysterisis 0.3)

Is this right?
mgpro

Matthias
26.11.2009, 12:12
it depends if you want to check the upper or lower limit

if you want a socket to be active above an upper limit ( = desired value + hysteresis) you need the function "decrease" and vice versa