Полезные программы/en — различия между версиями

Текущая версия на 10:35, 5 октября 2018

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1 Useful programs

Useful programs

Run script on rising or falling edge of the discrete signal

The script needs to be called on register's change. Inside the script, you need to check the current state of this register and perform corresponding actions either on the front (current state = 1) or on the falling edge (= 0). Example of the script:

Реализация универсального таймера (TON TOFF)

Таймер сравнивает свое текущее состояние с состоянием на входе:

текущее состояние = 0, вход = 1 - таймер включит выход через время задержки onDelay. Таймер TON получится если указать время offDelay = 0.
текущее состояние = 1, вход = 0 - таймер выключит выход через время задержки offDelay. Таймер TOFF получится если указать время onDelay = 0.

Для работы таймера необходимо завести 2 DS регистра типа Unix time и Bit и присвоить им имена (алиасы) вида "<Имя1>", "<Имя1>_out". В первом будет хранится время след. переключения, во втором - текущее состояние таймера.

function TimerOnOff(bool_input, onDelay, offDelay, tmrAlias)
--                    bool     seconds   seconds   string 
    local outAlias = tmrAlias.."_out"
    local curTmrState = (GetReg(outAlias) == 1) ; DEBUG("curTmr  State "..tostring(curTmrState))
                                                  DEBUG("bool_input = "..tostring(bool_input))
                                                
    if (bool_input == curTmrState) then 
        WriteReg(tmrAlias, now) ;                 DEBUG("timer input match state ") 
        return curTmrState  -- as bool 
    elseif bool_input then 
                                                    DEBUG("countdown for onDelay = "..(onDelay - (now - GetReg(tmrAlias))))
         if now - GetReg(tmrAlias) > onDelay then                                              
                WriteReg(outAlias, 1)
                                                    DEBUG("detected ON state after delay ")
                return true 
          end 
    else 
                                                    DEBUG("countdown for offDelay = "..(offDelay - (now - GetReg(tmrAlias))))
        if (now - GetReg(tmrAlias) > offDelay) then                                              
                WriteReg(outAlias, 0)
                                                    DEBUG("detected OFF state after delay ")
                return false  
        end     
     end  -- 
    return  curTmrState  -- output rerurned as bool for simple usage in IFs

end -- function

Пример использования:

Например есть два дискретных входа с датчиками реле низкого и высокого давления. Их состояние читается и переводится в переменную типа bool для упрощения последующих операторов сравнения. Функция также возвращает bool, чтобы ее можно было сразу использовать в операторах сравнения без дополнительных операторов if.

                                               DEBUG(" hotWater timer call ")
local DI2 = (GetReg(39) == 1) -- hotwater low pressure   
local DI3 = (GetReg(40) == 1) -- hotwater high pressure   
local hotWater = TimerOnOff((DI2 or DI3), 15, 15, "Tmr2") -- 15 seconds delay for both on and off .   

-- or like this 
if TimerOnOff(((GetReg("hotWaterLowPressure") == 1) or (GetReg(hotWaterHighPressure) == 1)), 15, 2, "Tmr2") then 
   -- do something 
end -- simple timer in one row !

Signalling (sound, relay, sms, viber, telegram) about connection errors

It is possible to analyze the scan time by the script and if it exceeds the acceptable limit, signal it in different ways. Below is an example of processing a large scan time with signaling to the message buffer and Viber.

cntdownFlag = false; -- timer countdown flag 
timeStmp = 0;  --  time stamp 
msgSent = false; -- message sent flag


function main (userId)
  -- read inputs
  local scan = GetReg(34); -- scan time 
  local c0 = GetReg(42); -- failed connection number 
  local SCANLIMIT = GetReg(886); -- scan time limit 
  local SCANDELAY = GetReg(887); -- error reaction time 
  -- 
  if (scan == nil)  or (c0 == nil) or (SCANLIMIT == nil) or (SCANDELAY == nil) then
   ERROR("scan / c0  was read as nil");
   return 0;
  end 
  -- read time 
  local now = os.time()
  -- message pattern 
  local msg1 = "Scan is long "..tostring(scan).." ".."ms, error in connection "..tostring(c0);
--
if (scan > SCANLIMIT) then  -- scan above limit
     if not cntdownFlag then 
         cntdownFlag = true
         timeStmp = now
     else 
         if (now - timeStmp) > SCANDELAY then 
             if not msgSent then 
                     AddAlertMessage(msg1)
                     SendViberMessage(398044391, msg1) -- Женя
                     msgSent = true
             end 
         end 
     end 
else -- scan in normal 
    if (cntdownFlag == true) and msgSent  then 
       AddInfoMessage("Скан вернулся к норме ")
       SendViberMessage(398044391, "Скан вернулся к норме ")
       msgSent = false
    end 
    cntdownFlag = false
 
end 

end -- main

In WebHMI there is a buzzer for the sound signal, and 2 output relays, which can be controlled for signaling (send a signal to the signal devices or the PLC about the problem).

Moving average

The moving average is useful for smoothing the values of parameters that have noises, pulsations. Algorithm of the moving average:
at the beginning of the filter on the sample, N values are counted by the arithmetic mean, after reaching the end of the sample, one element is discarded (by dividing the sum by the length of the queue), a new one is added instead of it, and the amount is again divided by the length of the queue.

-- globals
mav_len = 20;   -- queue length 
queue_fill = 0; -- queue fill index 
av_sum = 0;     -- accumulator moving average 


function main (userId)


local in_value, tmp_var, out_value  = GetReg(26), 0, 0; -- read input 
   
if (queue_fill < mav_len) then -- queue not filled
    av_sum = av_sum + in_value; -- accumulating sum 
    queue_fill = queue_fill +1; -- and index 
else                            -- now filled queue
    tmp_var = av_sum / mav_len; -- store one element 
    av_sum = av_sum - tmp_var + in_value; -- subtract and add 
end
-- 
if (queue_fill == mav_len ) then
      out_value = av_sum / mav_len; -- get moving average
    else
      out_value = av_sum / queue_fill; -- arithmetic mean 
end
WriteReg("Tout_mav", out_value) -- 

end

PID - control

An example of implementing a PID controller in WebHMI:

G_LIMIT = 100 -- output limit 
--
function main (userId)
  -- local vars
  local now = os.time()
  local nexTime = GetReg("nextPidTime")
  local CYCLE_TIME = GetReg("pidCycleTime")
  
  -- pid settings
  local Kp = GetReg("Kp") -- Proportional part (DS1400@WH Valve control)
  local Ti = GetReg("Ki") -- Integral time constant (DS1404@WH Valve control)
  local Td = GetReg("Kd") -- Diff. constant  (DS1408@WH Valve control)
  local Err, dErr, iSum_Limit = 0, 0, 0 
  local Int_sum = GetReg("pidIntegral") -- integral accumulator 
  local intPart = 0 -- integral part 
  local G = GetReg("pidOut") -- pid output 
  
  -- process 
  local PV = GetReg(1436) -- power  (PWR0@Scylar 8 INT)
  local Sp = GetReg("targetPowerSp") 
  
                                    DEBUG_("seconds left for PID cycle = "..tostring(nexTime - now))
    -- condition of work             
  local auto = (GetReg("auto_mode") == 1) -- auto mode is on (ds1176@WH Global)
  local heatDemand = (GetReg("heatDemand") == 1)
  
if auto then 
  
  if heatDemand then 
                                    -- PID - loop 
          if (now >= nexTime) then 
                                                          DEBUG_("PID compute cycle")
                WriteReg("nextPidTime", now + CYCLE_TIME)
                Err =  Sp - PV -- get error 
                                                    DEBUG_("sp pv Err = "..Sp.." "..PV.." "..Err)
                dErr = Err - GetReg("pidPrevError") -- get error tendency 
                                                    DEBUG_("dErr = "..dErr)
                    -- calc. integral limit
                iSum_Limit = (G_LIMIT * Ti / Kp) / 5
                                                            DEBUG_("iSum_Limit = "..iSum_Limit)
                
                            -- PID loop 
                    --check integral part 
                                                            DEBUG_("prev Int_sum = "..Int_sum)
                                                            if (intPart <= iSum_Limit) and (intPart >= 0.0) then
                    Int_sum = Int_sum + Err -- accumulating integral of error
                                                   DEBUG_("added error to Int_sum ")
                                                            
                    elseif Int_sum < 0 then
                        Int_sum = 0
                    else
                        Int_sum = iSum_Limit -- strict integral part 
                    end
                    if (Ti == 0) then 
                        intPart = 0 
                    else 
                        intPart = (1/Ti)*Int_sum
                    end 
                    
                    
                                                            DEBUG_("new Int_part = "..intPart)
                G = Kp * (Err + intPart + Td*dErr)
                                                            DEBUG_("Calculated G as "..G)
                G = Round(G)
                                                            DEBUG_("Rounded G as "..G)
                    -- check output for limits 
                if G < 0 then
                    G = 0  
                end
                if G > G_LIMIT then
                    G = G_LIMIT
                end
                
                WriteReg("pidPrevError", Err) -- remember previous error 
                WriteReg("dErr", dErr) -- 
                WriteReg("pidIntegral", intPart) -- remember integral 
                WriteReg("pidOut", G) 
                WriteReg("posSPinput", G) -- output for valve position
        end -- time stamp 
  else 
                DEBUG_("no heatDemand") -- 
      G = 0 
  end -- heatDemand 
                -- DEBUG_("PID_out = "..G) 
                WriteReg("pidOut", G) 
                WriteReg("posSPinput", G)
end -- if auto 

end -- main 

-- rounding  
function Round(var)
    
    local integer, fraction = math.modf(var)
    
        if fraction >= 0.5 then 
            integer = integer + 1
        end 
    
    return math.floor(integer)
end 

------ debug printing ------
thisScriptID = 45

function DEBUG_(str)
                --ERROR("entered DEBUG_ in"..thisScriptID.." script");
local i = 0;
local tmp = "";
local id = tostring(thisScriptID);
local debug_id = GetReg("debug_IDs");

local capture_mask = "%s+(%d+)%s+"

while true do 
i,_, tmp = string.find(debug_id,capture_mask,i+1)

    if (i == nil)  then 
        break -- not found
    end  
    -- найдено
    if (tmp ~= "0") then 
        -- found , check equality 
        if (tmp == tostring(thisScriptID)) then 
             DEBUG(str)
             return 0
        end 
    end 
end 

end -- DEBUG_
------------------------------

This algorithm is typical for use in PLCs. Because the regulator is run at regular intervals, i.e. diff. and int. the components are always computed on the same time scale, so it is not necessary to divide and multiply them by time to obtain the derivative and integral, we can select the time constants Ti, Td. In this algorithm, Ti is an inverse quantity (the larger its value, the smaller the contribution of the integral error)

Running hours meter

The running hour meter is convenient for automatically generating a message about the need for routine work for the equipment unit, changing the lead pump in the pumping group to equalize the operating time, and so on.

An example of the implementation of the run hour meter in WebHMI (the program runs in each scan):

-- globals 
run_state = false; -- to remember current state
function main (userId)
  -- locals
  local check_mask = tonumber("0000100000000000",2); -- bit mask to check rotation bit in frequency inverter FC 51 Danfoss
  local run_status = (bit.band(GetReg(109),check_mask) ~= 0); -- check result as a bool var 
  local now = os.time(); -- current system time 
  local time_diff = 0; -- time difference between current time and last call time


-- catching edge of the unit state 
  if (not run_state) and run_status then 
      WriteReg("P43StartTime", now); -- unit start time
  end


-- count time 
 if run_state then 
     time_diff = (now - GetReg("P43StartTime")); -- calc. time diff. 
     WriteReg("P43RunTime", GetReg("P43RunTime")+time_diff); -- increase meter 
     WriteReg("P43StartTime", now); -- overwrite start point 
 end 
 run_state = run_status
end

The timekeeping registers and time stamps should be made non-volatile.

Time Circulation algorithm (together with redundancy function)

This algorithm is used in systems where it is necessary to alternate the operation of mechanisms (pumps, fans, air conditioners) over time, or on the run hour meters. For example, a set of 2 units is used, which must be alternated in time. If an error occurs on some unit, then the algorithm starts working only on the working (redundancy function). An example of setting the required registers is given below:

For simplicity and clarity, it is better to split the scripts into functional modules that can be quickly analyzed and placed in the right order in the program list. The first script looks at the errors and if they do not exist, the air conditioners alternate in time.

CIRCULATION_TIME = 30; -- for tests circulation time is short 


function main (userId)
  --[[
  if there are no errors, then circulate over time 
  If there is an error on one of the air conditioners, it is excluded from the rotation
  if there are errors on both, then we stand 
  --]]
local acError1, acError2 = (GetReg("acError1") == 1), (GetReg("acError2") ==1) ; -- errro on a/c #1 (DS101@webmi)
local switchTime = GetReg("switchTime"); -- next switch over time (DS103@webmi)
local now = os.time()
local curActiveAC = GetReg("activeAC"); -- active a/c (DS100@webmi)


if (not acError1) and (not acError2) then 
    -- work on circulation
    if (now >= switchTime) then 
        if (curActiveAC == 1) then 
            WriteReg("activeAC", 2);
        else 
            WriteReg("activeAC", 1);
        end
        WriteReg("switchTime", now + CIRCULATION_TIME);
    end 
elseif acError1 and (not acError2) then 
        WriteReg("activeAC", 2);
elseif acError2 and (not acError1) then 
        WriteReg("activeAC", 1);
else
        WriteReg("activeAC", 0);
end -- if no errors 


end -- main

The second script looks at what kind of conditioner is now active, and performs the necessary actions. In a script, this is just debugging, but there may be commands for controlling the infrared transmitter for issuing the desired command, writing to the message log and switching, etc.

function main (userId)
  --[[
     turn on selected a/c depending on pointer
  --]]
  local pointer = GetReg("activeAC"); -- active conditioner (DS100@webmi)


if (pointer==0) then 
      DEBUG("all off")
      return 0
  elseif 
      (pointer==1) then 
          DEBUG("turn on a/c #1");
  else 
          DEBUG("turn on a/c #2");
      
  end -- if 
end

Also here you need a script that will expose the flags of errors of work on certain conditions, read the status of the protection devices, the error registers on the interface, and so on.

3-point control for a valve or servo

A 3-point method is used to control the position of the valve, servo, gate valve, etc., when 3 wires are used to control the drive - 'common', 'power UP', 'power - DOWN'. Such drives may or may not be equipped with end position sensors. Sometimes, in the absence of position sensors and low requirements for positioning accuracy, an algorithm can be used when the drive leaves down or up (either one position sensor or one command for a time longer than the valve's full travel time), initializes the coordinate, and then go to the specified position.

To determine intermediate positions, a calculated value is used, determined from the characteristics of the 'full path time', which can also be determined experimentally. As mentioned above, relatively complex and branched algorithms in WebHMI are better to divide into functionally complete and simple programs, the interaction and synchronization between them can be done using internal registers.

The
Below is a variant of 3-point control for a valve with 2 end sensors. The program is divided into 6 parts:

v3 OpenClose Valve Manual - manual control program,

v4 Auto Valve Control - main program. do homing on very first call, and if set in current position are no equal move into the desired direction when set positions are limits, then keeps on current command till the limit switch is reached

v5 LatchStart_Time - catches start time

v6 CalcNewPosition - calculate path done like time since start time while valve in motion (this path is checked in v4).

v7 Limit sw reaction

v8 Drop Cur Cmd on Manual mode - when manual mode selected, clears current cmds

At the beginning of the programs, the order of the required execution order (v3..v8) is indicated, since the necessary order of program execution can change undesirable, for example, when sorting programs and inaccurate 'dragging' programs in the list. Thus, the prefix reminds you of the desired order, it can also reflect the functionality of the script - 'v' Valves, 't' - temperature control, etc. It is more convenient to navigate in large lists and refer to it.

Script are given below: </ p> v3

------- Manual control from dashboard buttons  -------------------
function main (userId)
  
  local button_value = GetReg("valveMan_code")-- pressed button code 
  local manual_mode = (GetReg("auto_mode") == 0) -- auto mode ON (ds1176@WH Global)


if manual_mode then


if (button_value == 10) then 
         WriteReg("openCmd", 1); -- opening command (DS1007@WH Valve control)
         WriteReg("closeCmd", 0)
    elseif (button_value == 5) then 
          WriteReg("closeCmd", 1); -- closing command (DS1008@WH Valve control)
          WriteReg("openCmd", 0)
    else
        -- invalid code - all off 
                                    DEBUG("Read button value as "..tostring(button_value));
        WriteReg("openCmd", 0)
        WriteReg("closeCmd", 0)
        WriteReg("inMotion_flag",0)
    end --if 
    
    -- catching start position, and time 
    if (button_value == 10) or (button_value == 5) then 
        WriteReg("startPosition", GetReg("curPosition")); -- start position and time (DS1020@WebHMI 3point control)
        WriteReg("startPosTime", os.time()) -- start time time stamp (DS1012@WebHMI 3point control)
        WriteReg("inMotion_flag",1)
    end
end -- manual_mode


end -- main -----------------------

v4

-- auto valve control ---- 
function main (userId)
    
  local now = os.time(); -- cur time
  local timeStmp = GetReg("endPosTime") 
  local auto_mode = (GetReg("auto_mode")==1)
  
if auto_mode then
  -- check if very first run 
  if (timeStmp == 0) and (not home_mode) then 
      WriteReg("homingBit",1)
                                DEBUG("timeStmp = 0, homing needed! ")
  end 
  
  local home_mode = (GetReg("homingBit") == 1)
  local full_close = GetReg("LLsw")


if home_mode then 
      -- go down till low limit sw 
               DEBUG("giving home_mode close cmd ! ")
      WriteReg("closeCmd", 1)
      
          if (full_close == 1) then 
                   DEBUG("full close ! ")
                
                WriteReg("closeCmd",0)
                WriteReg("endPosTime", now) to avoid homing again
                WriteReg("homingBit",0)
                WriteReg("curPosition", 0) -- current valve position
          end
      return 0  -- 
  end -- home mode 
  
  --MAIN PART ---- 
                           DEBUG("-------- auto valve control ")
  
  local openingStatus = (GetReg("openCmd") == 1)
  local closingStatus = (GetReg("closeCmd") == 1)
  local inMotionFlag = openingStatus or closingStatus
  
  local target_dir= 0
  local posSV = GetReg("posSetpoint"); -- position setpoint 
  local posPV = GetReg("curPosition"); -- current position 
  
  local startTime = GetReg("startPosTime");
  local startPos = GetReg("startPosition");
  local pathdone = 0; 
  
  local OpenSw = GetReg("HLsw"); -- full open limit sw 
  local CloseSw = GetReg("LLsw"); -- full close limit sw
  
                            DEBUG("posPV  "..tostring(posPV).." pos SV"..tostring(posSV))
      -- Already moving
      if inMotionFlag then 
        -- full closed 
          if (closingStatus) and (posPV <= posSV) then 
              -- if 0 is setpoint then move till the physical limit sw 
              if (posSV == 0) and (not CloseSw) then 
                   WriteReg("closeCmd", 1)
                   return 0 -- exiting, cmd will be off in v7 script
              end 
                  WriteReg("closeCmd", 0)
                  WriteReg("inMotion_flag",0)
            end 
        -- full open ?
          if (openingStatus) and (posPV >= posSV) then 
             --- if 100 is setpoint then move till the physical limit sw 
                  if (posPV == 100) and (not OpenSw) then 
                       WriteReg("openCmd", 1)
                       return 0 --exiting the command will be off in v7 script 
                  end 
              WriteReg("openCmd", 0)
              WriteReg("inMotion_flag",0)
          end 
      -- stopped but not in position ?
       else 
           if (posSV ~= posPV) then 
               target_dir = (posSV - posPV)/math.abs(posSV - posPV); -- определить знак
                                            DEBUG_("target_dir =  "..tostring(target_dir));
               if (target_dir > 0) then 
                   WriteReg("openCmd" , 1);
                                            DEBUG_("will open...")
               else 
                   WriteReg("closeCmd" , 1);
                                            DEBUG_("will close...")
               end
            WriteReg("inMotion_flag", 1) -- sets in motion flag 
           end
  end -- auto mode motion control 


end -- auto_mode
end -- main

v5

-- LatchStart_Time ---
function main (userId)
    
                 DEBUG("Entered  latch start time and position");
  -- Add your code here
  local flag = (GetReg("inMotion_flag") == 1) ; -- in motion  (DS1016@WebHMI 3point control)
                 DEBUG("motion flag = "..tostring(flag))
  if flag then 
                  DEBUG("now flag = 1")
      WriteReg("startPosition", GetReg("curPosition")) -- start position (DS1020@WebHMI 3point control)
      WriteReg("startPosTime", os.time()) -- start time stamp (DS1012@WebHMI 3point control)
end 


end

v6

--- CalcNewPosition
-- constants
FULLPATH = 127  -- full close -> full open time 
K = 100 / FULLPATH ; -- travel time to position coef.


function main (userId)
    
                            DEBUG("Entered #5 script, calc. cur position");
  local now = os.time()
  local open_sts = (GetReg("openCmd") == 1)
  local close_sts = (GetReg("closeCmd") == 1)
  local inMotionFlag = (open_sts or close_sts) 
                            DEBUG("in motion flag = "..tostring(inMotionFlag))
  
  local cur_dir = 0 -- current direction
  local posPV = GetReg("curPosition") -- current position 


-- 
  local startTime = GetReg("startPosTime")
  local startPos = GetReg("startPosition")
  local pathdone = 0 
  
  -- moving now
  if inMotionFlag then 
      -- detect direction
      if open_sts then 
            cur_dir = 1
      else 
            cur_dir = -1
      end 
  pathdone = GetPathDone(startTime, now)  
  varPos = startPos + cur_dir*pathdone
      
      -- check for valid range 
      if (varPos < 0) or (varPos > 100) then 
                            DEBUG("new varPos calculaed outside limits, cur value "..tostring(varPos))
         if (varPos < 0) then varPos = 0 end 
         if varPos > 100 then varPos = 100 end 
      end 
                        DEBUG("startPos , pathdone = , new varPos  "..tostring(startPos).." "..tostring(pathdone).." "..tostring(varPos))
      WriteReg("curPosition", varPos); -- writing new position 
   end -- auto mode motion control 
end -- main 



function GetPathDone(startTime, curTime)  
  
    local curPos = (curTime - startTime) * K;
    local remainder = curPos - math.floor(curPos)
    if (remainder >= 0.5) then 
        -- rounding
        curPos = math.floor(curPos) + 1
    else 
        curPos = math.floor(curPos) 
    end
    return curPos
end

v7

-- Limit sw reaction------------
function main (userId) 
    
  local now = os.time();
  local open_sts = (GetReg("openCmd") == 1)
  local close_sts = (GetReg("closeCmd") == 1)
  
  local full_close = (GetReg("LLsw") == 1)
  local full_open = (GetReg("HLsw") == 1)
  
  if (full_open or full_close) then 
   
          if full_open then

              WriteReg("curPosition", 100);
              WriteReg("openCmd", 0);
              WriteReg("valveMan_code", 0); -- for manual mode
          end 
          
          if full_close then 
              WriteReg("curPosition", 0)
              WriteReg("closeCmd", 0)
              WriteReg("valveMan_code", 0) 
          end 
          
      WriteReg("inMotion_flag", 0)
      WriteReg("endPosTime", now)
    
  end 
  
  -- show current valve status
   if (not open_sts) and (not close_sts) then 
      WriteReg("valveStatus", 0) -- stopped
  elseif open_sts then 
      WriteReg("valveStatus", 1); -- opening
  else 
      WriteReg("valveStatus", 2); -- closing
  end 
  
end -- main --------------------------------

v8

------ v8 Drop Cur Cmd on Manual mode ---- 
function main (userId) 
    local auto_on = (GetReg("auto_mode")==1) -- work on register change
    
    if not auto_on then 
                                    DEBUG_("Dropped cmds in manua mode ! ")
        WriteReg("openCmd", 0)
        WriteReg("closeCmd", 0)
        WriteReg("inMotion_flag",0)
    end 
end -- main

Полезные программы/en — различия между версиями

Текущая версия на 10:35, 5 октября 2018

Содержание

Useful programs

Run script on rising or falling edge of the discrete signal

Реализация универсального таймера (TON TOFF)

Signalling (sound, relay, sms, viber, telegram) about connection errors

Moving average

PID - control

Running hours meter

Time Circulation algorithm (together with redundancy function)

3-point control for a valve or servo

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