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Shadoww
01.02.2012, 15:59
I have what is probably an easy programming logic question, just can't seem to get the logic right.

I have a Calcium Reactor that is PH controlled by PH probe 2.

PH - probe 1 is the normal tank water reading. What is happening is that the calcium reactor is maintaining 6.7ph all the time and dripping into the refugium to add calcium, overnight when the tank normally dips in PH the calcium reactor output is taking it even lower.

What I want to do is setup a programing logic based on the two PH probes to prevent the CO2 from being turned on when the tank PH dips below 8. I thought about using this, but I don't think it will work;

G5 = Input 1 pH-value 2 Decrease
Inupt 2 pH-value 1 Increase

Function = AND

And the set the socket that controls the CO2 to Logic 5, for some reason this does not seem like it would work correctly. Any suggestions??

Blahenazo
01.02.2012, 20:40
eheum , you might have lost me what is the point of using the sensor of the calcium reactor in this logic ??? , I understand what you want to do it , but IMHO its not the good solution for your problem


playing with PH2 has no importance to affect your dip ( at least not in a short term ) , the water in your reactor ( if its decend size ) will take way to long time to increase the ph, and because its so low it will take a even longer time to affect your tanks ph in a good way AND at the same time if you let your ph in your calcium reactor increase it will be less efficient at the same time.


its beter to stop dosing your reactor water to prevent or at least slow down the dip instead of playing the ph of the reactor. After the dip the dosing can again procede and because your reactor still has the same ph , it might even more efficient ( because it has been cycling internally , while there was no dosing )

offcourse in this way you need 2 sockets: 1 socket for co2 and 1 socket for dosing the reactor water.

Shadoww
01.02.2012, 21:12
I see your point, but do to the way that my system is setup there is no way to slow down or stop the Calcium reactor from dosing. So for the couple of hours that there is a tank dip I figured I could simply let the calcium reactor come up a bit in PH. Hence that I why I was looking for a logic that would only allow the CO2 to turn on if both conditions were met.

Wirus
01.02.2012, 21:46
You can create virtual sensors to control values different from the main value of a sensor.

For your system you have to create two virtual sensors of the ph probes and set the needed vaues (may different from the real sensors). The rest is to glue them together with logic

Shadoww
01.02.2012, 21:50
Ok so if I created a Virtual for the tank PH call it PH3 and a Virtual for reactor PH call it PH4

Set PH3 to 8.0
Set PH4 to 6.5

Then setup the logic gate as:

Input 1 pH-value 4 Decrease
Inupt 2 pH-value 3 Increase

Function = AND

Then set the CO2 socket to the Logic would it do what I am looking for?

Wirus
01.02.2012, 23:17
I haven´t understand your wish en detail but it seems wrong for me .... you have done:

If input 1 pH-value 4 (reactor PH ) is highter than 6.5 (=decrease) AND Input 2 pH-value 3 (tank PH) is lower than 8.0 (increase) the CO socket will switched on.

Makes no sense for me. Maybe you shoud interchange increse and decrease of the probes.

Shadoww
02.02.2012, 00:48
I see what you are saying, I guess I will have to rethink it. What I am looking to do is;

If the ph of the reactor needs to be lowered AND the tank ph is above 8.0 then the CO2 socket will come on. If the ph of the reactor needs to be lowered but the tank ph is below 8.0 then the CO2 socket will not turn on until the tank ph is back in normal range.

Any ideas for that logic?


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Wirus
02.02.2012, 01:04
Any ideas for that logic?

If the ph of the reactor is > 6.5 (needs to be lowered/decreased) AND the tank ph is above 8.0 (needs to be lowered/decreased) then the CO2 socket will come on.

So use

Ok so if I created a Virtual for the tank PH call it PH3 and a Virtual for reactor PH call it PH4


Set PH3 [tank] to 8.0
Set PH4 [reactor] to 6.5

Then setup the logic gate as:

Input 1 pH-value 4 Decrease
Inupt 2 pH-value 3 Decrease

Function = AND

This will result in: Tank ph > 8.0 AND reactor ph > 6.5 => CO2 on
Consequence: If tank ph < 8.0 OR reactor ph < 6.5 => CO2 off

I suggest, that´s what you need

Shadoww
02.02.2012, 01:36
That makes much more sense, I will give this a try. Thank you SO much for the help I really appreciate it.


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