heater Control

[honselbonsel]

Hi Community,
right now i am testing to install an heater control for the whole house. While i am doing some evaluation - dry run. I had the following effect when steering the valves of the Wallheaters.
In the first version i implemented an logic like - if temp goes below point then valve on - to haet and so on. Works fine but.

if the incoming temp is like 0.1 degress changing the valve goes on and then off / on /off /off so it flaps for measuring tolerance.

The Idea was now to say - lets check the temp over a period of time like 2 minutes and if the temp continuously stays below.... then set a switch so that the heating valve will get on.

The question is now - Is there a simple way in domoticz to measure a value over a period of time like in that graphical stats shown. There must be some access to this data? or just measuring - maybe an lua script may do something.

Thank You - for ideas

[Stephan83]

You can add a HYSTERESIS to you code. By doing that the difference between the setpoint and the actual switch moment will be a bit more (depending on the value you add).

An example:

in the top of your dzvents code:

Code: Select all

local HYSTERESIS = 0.2 -- temp has to drop this value below setpoint before boiler is on again

At the calculation:

Code: Select all

  domoticz.devices('Woonkamer temp').temperature < (domoticz.devices('Woonkamer thermostaat').setPoint - HYSTERESIS)

I think you can also do this in blocky but I did not try.

I used the same mechanism in my multizone heating system see:
viewtopic.php?f=34&t=25882

[honselbonsel]

Hi, thanks for the reply.
menawhile i developed some ruby scripts which i run as cronjob every 5 minutes.
I share the code here all comments are german- but it is very simple and therfore self explaining.
the point ist that the domoticz db is getting updated every 5 mins. so i have no flapping in temperature.
I have a script for each room. And so i test now the relais and all that stuff

Code: Select all

require 'json'
require 'net/http'
require 'net/https'
require 'sqlite3'
require 'uri'
require 'logger'
require 'date'

d = Time.now
d = d.strftime("%d%m%Y-%H-%M-%s").to_s
logfile = "/var/log/heatscript#{d}.log"
#create Logs of script
logger = Logger.new(logfile)


tempist = 0
#tempSoll
uritsoll = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=devices&rid=34")
restsoll = Net::HTTP.get_response(uritsoll)
resulttsoll= restsoll.body
parsedtsoll = JSON.parse(resulttsoll)
#puts parsed
tempsoll = parsedtsoll ['result'][0]['Data'].to_f
name = parsedtsoll ['result'][0]['Name']
logger.info "Temperatur Soll: #{tempsoll} Grad"

#awaytemp
#
uriawaytemp = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=devices&rid=42")
restawaytemp = Net::HTTP.get_response(uriawaytemp)
resultawaytemp = restawaytemp.body
parsedawaytemp = JSON.parse(resultawaytemp)
awaytemp = parsedawaytemp ['result'][0]['Data'].to_f
#puts "AwayTemp Soll: #{awaytemp} Grad"
logger.info "AwayTemp Soll: #{awaytemp} Grad"

#presence
uripresence = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=devices&rid=72")
restpresence = Net::HTTP.get_response(uripresence)
resultpresence= restpresence.body
parsedpresence = JSON.parse(resultpresence)
presence = parsedpresence ['result'][0]['Status']
#puts "Presence Status: #{presence} "
logger.info {"Presence Status: #{presence} " }

#nighttemp setpointnighttemp41
urinighttemp = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=devices&rid=34")
restnighttemp = Net::HTTP.get_response(urinighttemp)
resultnighttemp = restnighttemp.body
parsednighttemp = JSON.parse(resultnighttemp)
nighttemp = parsednighttemp ['result'][0]['Data'].to_f
#puts "Nachttemp Soll: #{nighttemp} Grad"
logger.info {"Nachttemp Soll: #{nighttemp} Grad " }

#zeitschaltuhrküche38
uritimeswitch = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=devices&rid=38")
resttimeswitch = Net::HTTP.get_response(uritimeswitch)
resulttimeswitch = resttimeswitch.body
parsedtimeswitch = JSON.parse(resulttimeswitch)
timeswitch = parsedtimeswitch ['result'][0]['Status']
logger.info "Zeitschaltuhr Status: #{timeswitch} "




#temp IST
db = SQLite3::Database.open "/pathto/domoticz.db"
db.results_as_hash = true
stm = db.prepare "select temperature from Temperature where DeviceRowID=66 order by rowid desc limit 1" 
resultset= stm.execute
  resultset.each do |row|
 # puts row
  $tempist =row["Temperature"].to_f

end

#subroutines Ventile
def valveon
 uriswon = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=command&param=switchlight&idx=13&switchcmd=On")
        response = Net::HTTP.get_response(uriswon)
end

def valveoff
 uriswoff = URI.parse("http://xxx.xxx.xxx.xxx:8080/json.htm?type=command&param=switchlight&idx=13&switchcmd=Off")
        response = Net::HTTP.get_response(uriswoff)
end


puts $tempist
#Logik: jemand zuhause ja und zeitschaltuhr an
#
#-----------------------------------
case presence
when "On"

	case timeswitch
	when "On"
	if $tempist < tempsoll
	logger.info "jemand da und tag Ventil auf"
	valveon
		else
	logger.info "jemand da und tag Ventil schliessen"
	valveoff
	end
	when "Off"
	#timeswitch off also Nachtzeit
    	if $tempist < nighttemp
      	logger.info "jemand da und nacht Ventil auf"
		valveon
        else
        loggerinfo "jemand da und nacht Ventil schliessen"
        valveoff
		end
               else
    logger.error "Error: Timeswitch has an invalid value (#{timeswitch})"
	end

when "Off"
	logger.info "Presence Status #{presence} Alle Abwesend"
	if $tempist < awaytemp
        logger.info "keiner da Ventil auf"
        valveon
	else
        logger.info "keiner daVentil schliessen"
        valveoff
	end
else
    logger.error "Error: Presence has an invalid value (#{presence})"
end