need help programming

**hani** · 19.10.2015, 22:22

I am running a freshwater tank, am trying to control my c02 what I want to do is:
I need co2 to come on at 7am till 3 pm, I want it to shut off during this period of time when ph reach 5.7.
after 3pm I want the co2 to shut off and the ph can drift all the way up (nocturnal changes only allow for 1 degree of ph shift).
any help
thanks

**CaptCrash** · 20.10.2015, 11:20

This shouldn't be too hard to sort out.
Note: I don't have a CO2 solenoid to test this with, so you will need to follow the logic and check each part.

Step 1 - Timer 1 (use another timer if this one is already used).
Create a timer to allow the CO2 solenoid to be operated only in the times you specify, in this case 7am to 3pm.

Click Process -> Timer 1
Set the following values
- Select Day Interval: Repeat all 1 days (or choose specific days of the week and select them all)
- Switch Mode Normal
- Click New
  - Set a start time of 7am
  - Set an end time of 3pm
Provide a Description for in GHL Control Centre and In device "Max CO2 on time"
Close the Timer 1 tab

Step 2 - pH value 1 (use another pH probe or a virtual probe if this one is already used).
Set the target PH on the probe.

In Probe/Sensor controls select the PH probe (ph-value 1 sensorindex=1)
Set the nominal value 5.7
If you are using this probe for some other task as well that requires a seperate nominal value, then create a virtual probe and use it rather than the physical probe (I am assuming the physical probe is fine).
Close the PH probe tab

Step 3 - G1 (use programmable logic if this one is already used).
Setup programmable logic to require both the timeframe and the PH value to be correct.

Click on Programmable logic
Double click on an unused logic item G1 in this case
Change Input 1 to be pH-value 1 Increase (or the probe you selected in step 2)

Note: Check that increase is correct here, I think that its right, but just make sure.

Change Input 2 to be Timer 1 (or the timer you selected in step 1)
Set the function to be AND
Provide a description of "On if pH needs to increase and its between 7am and 3pm"
Close the Programmable logic tab

Step 4 - S1 (use the socket that turns on/off the CO2 flow).
Control the solenoid with the programmable logic we just created

Click on System -> Socket functions
Double click the socket that controls your CO2 solenoid e.g. S1 in my example
Set the function to be programmable logic G1 (or what ever programmable logic you used in step 3)
Set the descriptions to be "On if pH needs to increase and its between 7am and 3pm"
Set a blackout delay if required (5 minutes). This will disable the CO2 when recovering from a power outage.
Close the socket functions tab

Optional Steps
If you would like the CO2 to be turned off during a feed pause or when the filter 1 is stopped, then make the following changes

Step 5 - G2 (use another programmable logic if this one is already used).
Create a programmable logic to check if the filter 1 is active and then only turn on if the other programmable logic is also on (between 7am and 3pm and pH needs to increase).

Click on Programmable logic
Double click on an unused logic item G2 in this case
Change Input 1 to be Programmable Logic G1 (or what ever programmable logic you used in step 3)
Change Input 2 to be Filter 1 (or which ever filter is used for your pumps)
Set the function to be AND
Provide a description of "On if pH needs to increase, between 7am and 3pm and pump on"
Close the programmable logic tab

Step 6 - S1 (use the socket that turns on/off the CO2 flow).
Update the control solenoid with the programmable logic to stop during filter 1 pauses

Click on System -> Socket functions
Double click the socket that controls your CO2 solenoid e.g. S1 in my example
Change the function to be programmable logic G2
Close the socket functions tab

Step 7 - Maintenance Functions.
You should also set the socket to be off during maintenance to ensure that CO2 is not released when the system is in maintenance mode.

Click on Extras -> Maintenance 1
Put a tick next to the click the socket that controls your CO2 solenoid e.g. S1 in my example
Change the state to be off
Close the Maintenance tab
Repeat this process for each Maintenance (2, 3 and 4)

This should do the job.

Testing
Items that you can check to make sure its doing what you want.

1. Set the time on the controller to be before 7am and check that the CO2 is off

set the pH nominal value to be 3, confirm the CO2 remains off
set the pH nominal value to be 9, confirm the CO2 remains off
set the pH nominal value back to 5.7

2. Set the time on the controller to be after 3pm and check that the CO2 is off

set the pH nominal value to be 3, confirm the CO2 remains off
set the pH nominal value to be 9, confirm the CO2 remains off
set the pH nominal value back to 5.7

3. Set the time on the controller to be between 7am and 3pm and check that the CO2 is on or off depending on the nominal value

set the pH nominal value to be 3, confirm the CO2 remains off
set the pH nominal value to be 9, confirm the CO2 is on
set the pH nominal value back to 5.7 (CO2 on or off will depend on measured value)

4. If you have done the optional parts, Press the feed pause with the time between 7am and 3pm and check that the CO2 is off