Logic control in 12 way relays

Ashley, thanks for your help! when I run the script I get the following error code. User script 8: attempt to call a table value stack trace back: userscript 8 in main chunk. It fails to log "got here"

Thanks Max W

 

Oops. Sorry, can't even copy my own code. The for statement was wrong. It should be paisr(boliers), not just boilers.

Code:

value = event.getvalue()
if value == 255 then
    SetCBusState(0, 56, 12, true)
end

if value == 0 then
    boilers = GetCBusByKW('Boiler') -- Get table once outside of loop
    for _, group in pairs(boilers) do --  ***** ***********CHANGE THIS HERE *********************
         value = group.data.target
         if value ~= 0 then -- Don't need to continue once we find one on
             break -- this exits from the loop
         end
    end
    if value == 0 then
        SetCBusState(0, 56, 12, false)
        log("got here")
    end
end

This is what I hate about Lua. Almost anything compiles but gives you meaningless run time errors.

 

Ashley, thanks for all of your time and patience ! I have just altered the code and it works.
But only when all of the UFH valve relays are on. If I have on relay off (UFH valve closed area temp satisfied) the boiler relay will intermittently pulse off and then back on. It seems like when the script I have running every 5 seconds to check the temperature and set point temperature. Thanks Max W

 

Can't really help here as I can't see your other code

 

Hi Ashley thanks fro all of your help. I ran your code and it works fine when the relays are operated by the edlt so my code is to blame. I have attached it. IM using a EDLT with a set point and a GA to adjust the set point up and down. This checks the actual temp and turns the relay on as required. But Im no expert there may be a better way to achieve this?

 

You need to have a dead band around your temperature setting. The temperature sensor will fluctuate slightly between reading, so when it's right at the set point it will continually go above and below the set point by a tiny amount and your code will continually turn the load on and off each 5 seconds. Generally 0.5 degrees is common, but you could reduce that depending on the fluctuations of the temperature reading.

e.g.

Code:

if set_temp > temp1 then
SetCBusLevel(0, 56, 1, 255, 0)
elseif set_temp <= (temp1 - 0.5) then  -- deadband of 0.5 degrees.
 SetCBusLevel(0, 56, 1, 0, 0)
end

Are you duplicating all this for each zone ??

 

Ashley, I have duplicated it for each zone, and have inputed the headband for each zone .
the Boiler relay still still drops out if any one zone is not calling. But if all zones are demanding the valve to open it stays on. I seems to happen when the resident script sleeps. This is set at 10s at the moment but I planned to set it to 60s.

 

I suggest you run the cbus diagnostic routine while you are changing zones. It will tell you which unit is turning off the boiler relay. If it is the SHAC, post all the current code again.

You could also put some more logging messages in your code to track what it is doing.

 

Thanks for all of your help I will try that and report back.