I dont understand

hvacman250

New member
I am reading this user guide as my 220 fills up with water, and I dont get this:

Take these examples where the statements are identical but the order is reversed; assume the time is 1pm (13:00) and the tank temperature is 81 degrees:

If Time 08:00 to 19:00 Then ON If Temp > 80.5 Then OFF
This outlet would be OFF

If Temp > 80.5 Then OFF If Time 08:00 to 19:00 Then ON
This outlet would be ON



Why? Isnt the temp being 81 shutting the outlet down? Why is it changed when reversed?

This is sooo much different than the Reefkeeper Lite!
 
I am reading this user guide as my 220 fills up with water, and I dont get this:

Take these examples where the statements are identical but the order is reversed; assume the time is 1pm (13:00) and the tank temperature is 81 degrees:

If Time 08:00 to 19:00 Then ON If Temp > 80.5 Then OFF
This outlet would be OFF

If Temp > 80.5 Then OFF If Time 08:00 to 19:00 Then ON
This outlet would be ON



Why? Isnt the temp being 81 shutting the outlet down? Why is it changed when reversed?

This is sooo much different than the Reefkeeper Lite!

The controller sets the state of the outlet by the last TRUE statement.

In this example:
If Time 08:00 to 19:00 Then ON (TRUE)
If Temp > 80.5 Then OFF (TRUE)
This outlet would be OFF

If Temp > 80.5 Then OFF (TRUE)
If Time 08:00 to 19:00 Then ON (TRUE)
This outlet would be ON
 
I believe that the way the Apex reads code is in order from top to bottom. So any code that comes after the previous line will essentially override that command if they contradict.

In your example situation one is saying they light goes on at the set time. If the temp condition happens it is then set to off. So the second line is conditional and overrrides the previous line when the condition is met. If that condition is never met the command is ignored. Now when the Apex cycles back around and read the program again. It will turn the lights on as per line one. Now if the temp condition is never met then it ignors line two and the light stays on.

In example two. The temp condition is read first and the outlet is turned off. The time condition line is second in line and therefore overrrides line one. So, regardless of the first line, if the time condition is met the light will be turned on. Since a time condition will always be met at that timeframe, when that time comes the temp condition is superceeded.

It completely has to do with the order. Any met condition will override the previous order.
 
Go back and read the paragraphs preceding those examples. There's a good discussion of how the outlet programming statements work, the internal outlet registers vs. the physical state of the outlet, etc. While it's true most of the time that the last true outlet statement sets the outlet's physical state, there are some exceptions to that like Defer and Min Time where it doesn't matter where those statements are located.
 
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