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OTee is all about openness, so any code produced on the platform can be exported for further processing in any IEC 61131 compliant application. To get you started quickly, we’ll import such a project file in this step. Start by using an example project, which uses a function block to simulate a heat exchanger and a built-in PID controller to steer the process towards the user’s target temperature set point. Paste the entire code below into an empty text editor and save the file as “heat_exchanger.xml”. (Some browsers won’t allow xml file downloads, hence the plain text.) 
<project xmlns="http://www.plcopen.org/xml/tc6_0201">
  <fileHeader companyName="Unknown" productName="Unnamed" productVersion="1" creationDateTime="2023-09-14T08:06:45"/>
  <contentHeader name="PlainProject" modificationDateTime="2023-09-14T08:09:26">
    <coordinateInfo>
      <fbd>
        <scaling x="0" y="0"/>
      </fbd>
      <ld>
        <scaling x="0" y="0"/>
      </ld>
      <sfc>
        <scaling x="0" y="0"/>
      </sfc>
    </coordinateInfo>
  </contentHeader>
  <types>
    <dataTypes/>
    <pous>
      <pou name="program0" pouType="program" globalId="e8ccb66e-809d-454b-a0a8-78a1173769dd">
        <interface>
          <localVars name="Heat exchanger" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="heatExhanger1" globalId="UUID_dea7bb00-2e78-4dcb-b6d1-113a92e35da9">
              <type>
                <derived name="FB_heat_exchanger"/>
              </type>
              </variable>
            <variable name="T1_in" globalId="UUID_d19837d6-16cf-4c21-be1e-2537db2d1708">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="40.0"/>
              </initialValue>
              </variable>
            <variable name="T2_in" globalId="UUID_a1aa3914-8f0e-4a0c-b9eb-4f65bcd991e1">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="10.0"/>
              </initialValue>
              </variable>
            <variable name="T1_out" globalId="UUID_dea60ef4-9050-4d41-8f59-c35cc35147f7">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="T2_out" globalId="UUID_c94d70d6-f598-48e3-859e-3a54a56d4394">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="q1" globalId="UUID_598aeceb-b2aa-4a71-95be-802e091f37de">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="140.0"/>
              </initialValue>
              </variable>
            <variable name="q2" globalId="UUID_db035859-7396-47b9-b697-0726b3dabf6e">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="60.0"/>
              </initialValue>
              </variable>
            <variable name="heatTransferNumber" globalId="UUID_b3e74e4a-3211-4e0f-816c-83b79a63f6e9">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="heatTransferArea" globalId="UUID_dde842ab-118c-412e-b5bd-4624fa6a679b">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="volumeDiscretization" globalId="UUID_312b6bdc-5cfe-49fc-afe3-4c6946fe85b2">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="inletFlow_WarmSide" globalId="UUID_3508ca76-be6b-4072-a00e-2727c8587fa0">
              <type>
                <REAL/>
              </type>
              </variable>
          </localVars>
          <localVars name="controller" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="Side2_controller" globalId="UUID_b1abd92f-0e4e-491d-ad1e-d8802d8fb773">
              <type>
                <derived name="PID"/>
              </type>
              </variable>
            <variable name="PID_kp" globalId="UUID_a0ea9830-b0cf-4199-a744-0199e86b7ec4">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="4.0"/>
              </initialValue>
              </variable>
            <variable name="PID_tr" globalId="UUID_4ae48a41-2e76-4e48-a54c-59698cbff4b1">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="100.0"/>
              </initialValue>
              </variable>
            <variable name="PID_td" globalId="UUID_85259f0c-7efe-4782-8bd4-0dcd24824a2a">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="0.0"/>
              </initialValue>
              </variable>
            <variable name="PID_AUTO" globalId="UUID_6ef2c8a7-c103-47ae-a9c2-f618759e3e9d">
              <type>
                <BOOL/>
              </type>
              </variable>
            <variable name="PID_sp" globalId="UUID_06727de3-14c8-4350-b69e-d9e5b2289c17">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="30.0"/>
              </initialValue>
              </variable>
            <variable name="valve_opening" globalId="UUID_6f1c9d87-72bb-464e-924b-843d2f3e59e3">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="PID_X0" globalId="UUID_0f2ae044-1fcb-42e9-ae66-c140c5a598a5">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="12.5"/>
              </initialValue>
              </variable>
          </localVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">(*                  Heat Exchanger&#13;
&#13;
side 1 In --&gt;  |  =====&gt;====&gt;====&gt;====&gt;====&gt; |  --&gt; side 1 Out&#13;
               |                             |&#13;
               |                             |&#13;
side 2 Out &lt;-- |  &lt;====&lt;====&lt;====&lt;====&lt;====  |  &lt;-- side 2 In&#13;
&#13;
max inlet flow :&#13;
  side 1 140 m3/h&#13;
  side 2 60 m3/h&#13;
&#13;
Play with the exchanger by changing the following values:&#13;
  T1_in,T2_in,q1,q2&#13;
&#13;
*)&#13;
&#13;
heatTransferArea := 37.0; (* m2 *)&#13;
heatTransferNumber := 4839.0; (* W/m2*K *)&#13;
volumeDiscretization := 40.0;&#13;
&#13;
heatExhanger1(&#13;
  Volume1 := 0.0047,    (* total volume of side 1 [m3]*)&#13;
  Volume2 := 0.0038,    (* total volume of side 2 [m3]*)&#13;
  Temperature1_In := T1_in,    (* Incoming T side 1 [C] *)&#13;
  Temperature2_In := T2_in,    (* Incoming T side 2 [C] *)&#13;
  q1 := inletFlow_WarmSide/3600.0,    (* Flow side 1 [m3/s] *)&#13;
  q2 := q2/3600.0,    (* Flow side 2 [m3/s] *)&#13;
  Ts := 0.1,    (* sample time [s]*)&#13;
  U := heatTransferNumber*heatTransferArea/volumeDiscretization,    (* thermal conductivity [W/K] *)&#13;
  &#13;
  Temperature1_Out =&gt; T1_out,&#13;
  Temperature2_Out =&gt; T2_out&#13;
);&#13;
&#13;
Side2_controller(&#13;
  (* Inputs *)&#13;
  AUTO := PID_AUTO,&#13;
  PV := T2_out,&#13;
  SP := PID_sp,&#13;
  KP := PID_kp,&#13;
  TR := PID_tr,&#13;
  TD := PID_td,&#13;
  X0 := PID_X0, (* start bias *)&#13;
  CYCLE := T#100ms&#13;
);&#13;
&#13;
(* output limitation *)&#13;
if Side2_controller.XOUT &lt; 0.0 then&#13;
  valve_opening := 100.0;&#13;
elsif Side2_controller.XOUT &gt; 100.0 then  &#13;
  valve_opening := 0.0;&#13;
else &#13;
  valve_opening := 100.0-Side2_controller.XOUT;&#13;
end_if;&#13;
inletFlow_WarmSide := q1*valve_opening/100.0;&#13;
&#13;
(* fuzzy antiwindup *)&#13;
if Side2_controller.XOUT &lt; 0.0 then&#13;
  PID_AUTO := false;&#13;
elsif Side2_controller.XOUT &gt; 100.0 then&#13;
  PID_AUTO := false;&#13;
ELSE&#13;
  PID_AUTO := true;&#13;
END_IF;</xhtml:p>
          </ST>
        </body>
        </pou>
      <pou name="density" pouType="function" globalId="6161acc0-14c1-46b1-b51c-d2700933c1b7">
        <interface>
          <returnType>
            <REAL/>
          </returnType>
          <inputVars name="varGroup_c33c" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="temperature" globalId="UUID_10f44a89-93d5-424f-b71d-ffb1dfe635c6">
              <type>
                <REAL/>
              </type>
              <documentation>temperature</documentation>
            </variable>
          </inputVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">(* Specific density water *)&#13;
&#13;
density := 1000.006621939&#13;
    + 0.00001626*temperature*temperature*temperature&#13;
    - 0.00602137*temperature*temperature&#13;
    + 0.02092985*temperature;</xhtml:p>
          </ST>
        </body>
        </pou>
      <pou name="heatCapacity" pouType="function" globalId="a1feb9c6-779a-49aa-ac73-8bcd110b5f7d">
        <interface>
          <returnType>
            <REAL/>
          </returnType>
          <inputVars name="varGroup_1a63" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="temperature" globalId="UUID_59694563-6f00-49c8-96c7-e7db4f2c76de">
              <type>
                <REAL/>
              </type>
              </variable>
          </inputVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">(* Specific heat capacity water *)&#13;
heatCapacity := 4201.7217960&#13;
   - 0.00013861*temperature*temperature*temperature&#13;
   + 0.03367866*temperature*temperature&#13;
   - 1.96518738*temperature;</xhtml:p>
          </ST>
        </body>
        </pou>
      <pou name="alpha" pouType="function" globalId="e8daafa3-a54c-427f-8228-d4497888d257">
        <interface>
          <returnType>
            <REAL/>
          </returnType>
          <inputVars name="varGroup_44a5" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="q" globalId="UUID_f1eb70ae-99a2-428f-bf27-bc509c20f59b">
              <type>
                <REAL/>
              </type>
              <documentation>flow (m/3)</documentation>
            </variable>
            <variable name="Ts" globalId="UUID_868a77ce-b93e-4e44-b803-6d193eb334e5">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="0.1"/>
              </initialValue>
              <documentation>sample time</documentation>
            </variable>
            <variable name="V" globalId="UUID_8b3ed086-197d-4724-b387-fd789b8160ee">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>volume</documentation>
            </variable>
          </inputVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">alpha := q*Ts/V;</xhtml:p>
          </ST>
        </body>
        </pou>
      <pou name="omega" pouType="function" globalId="3180a3cc-b533-44a5-a63d-16adfe1eb484">
        <interface>
          <returnType>
            <REAL/>
          </returnType>
          <inputVars name="varGroup_44a5" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="U" globalId="6c127374-6183-430e-a166-a9bdbb26d81e">
              <type>
                <REAL/>
              </type>
              <documentation>thermal conductivity</documentation>
            </variable>
            <variable name="Ts" globalId="f85333d2-0f07-4e8e-bb33-8d4f2e10d7cd">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="0.1"/>
              </initialValue>
              <documentation>sample time</documentation>
            </variable>
            <variable name="V" globalId="UUID_2475f87b-2a02-4215-b5dd-85bf73350098">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>Volume</documentation>
            </variable>
            <variable name="Temperature" globalId="UUID_82c88102-ab31-4d84-8784-fa6e7f510050">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="20.0"/>
              </initialValue>
              <documentation>temperature</documentation>
            </variable>
          </inputVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">omega := U*Ts/( density(Temperature)*heatCapacity(Temperature)*V );</xhtml:p>
          </ST>
        </body>
        </pou>
      <pou name="FB_heat_exchanger" pouType="functionBlock" globalId="855a4b3b-fa42-4810-aee1-0678c4bcd27f">
        <interface>
          <localVars name="constants" constant="true" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="numberOfTanks" globalId="UUID_9a548eb4-382c-4d8a-b17b-f67cd785d317">
              <type>
                <INT/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="40"/>
              </initialValue>
              <documentation>discretization </documentation>
            </variable>
          </localVars>
          <localVars name="varGroup_ffa7" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="index" globalId="UUID_7d3d0ea0-4a43-44c9-a4c7-e7665f98c9ac">
              <type>
                <INT/>
              </type>
              </variable>
            <variable name="T1_k1" globalId="UUID_f0123697-0162-4e8e-ab9f-02099f49c9f3">
              <type>
                <array>
                  <dimension lower="0" upper="40"/>
                  <baseType>
                    <REAL/>
                  </baseType>
                </array>
              </type>
              <documentation>T1[k+1] Temp side 1, next timestep</documentation>
            </variable>
            <variable name="T2_k1" globalId="UUID_e5c0fbda-f24a-40bd-93e2-fd7054ffae0f">
              <type>
                <array>
                  <dimension lower="0" upper="40"/>
                  <baseType>
                    <REAL/>
                  </baseType>
                </array>
              </type>
              <documentation>T2[k+1] Temp side 2, next timestep</documentation>
            </variable>
            <variable name="T1_k" globalId="UUID_f5cdf804-9f3f-4c83-8e96-18c93236d12b">
              <type>
                <array>
                  <dimension lower="0" upper="40"/>
                  <baseType>
                    <REAL/>
                  </baseType>
                </array>
              </type>
              <documentation>T1[k+1] Temp side 1, this timestep</documentation>
            </variable>
            <variable name="T2_k" globalId="UUID_6662a384-6fc9-442d-b3c7-2b53ea4b1eb7">
              <type>
                <array>
                  <dimension lower="0" upper="40"/>
                  <baseType>
                    <REAL/>
                  </baseType>
                </array>
              </type>
              <documentation>T2[k+1] Temp side 2, this timestep</documentation>
            </variable>
            <variable name="isInitialized" globalId="UUID_96bfba8f-0e1a-420b-ab83-85bb8c295819">
              <type>
                <BOOL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="false"/>
              </initialValue>
              </variable>
          </localVars>
          <localVars name="varGroup_2368" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="t1k1" globalId="UUID_da985cf1-1d06-4c3c-9d18-2e6979d711b7">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="a1" globalId="UUID_0b5f5716-5565-4756-8f9e-b0b604d69582">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="b1" globalId="UUID_befd64d1-08ca-4b20-9782-098892026c2c">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="o1" globalId="UUID_1a3ffe09-bbde-482b-b7c5-f23c2326e087">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="dens" globalId="UUID_7abfe8b1-4fb0-4fe0-9031-8aabf6e80e09">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="heatCap" globalId="UUID_c8a54673-9a78-4be5-92f4-d7ea987e853c">
              <type>
                <REAL/>
              </type>
              </variable>
          </localVars>
          <inputVars name="varGroup_fc5c" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="Volume1" globalId="UUID_cbdefb07-4829-47d0-ac1f-744faca13cc3">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>total volume of side 1 [m3]</documentation>
            </variable>
            <variable name="Volume2" globalId="UUID_492e29bd-f8cf-4d45-9f51-0c0f4f4af7de">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>total volume of side 2 [m3]</documentation>
            </variable>
            <variable name="Temperature1_In" globalId="UUID_7ab48dd3-2cfc-4f29-a025-f9b32871ba61">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="20.0"/>
              </initialValue>
              <documentation>Incoming T side 1</documentation>
            </variable>
            <variable name="Temperature2_In" globalId="UUID_d1b354fc-d89e-4115-9faf-23c370a57831">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="20.0"/>
              </initialValue>
              <documentation>Incoming T side 2</documentation>
            </variable>
            <variable name="q1" globalId="UUID_f6f6e4ce-9c02-41fb-a52b-8eab8f737c29">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>Flow side 1 m3/s</documentation>
            </variable>
            <variable name="q2" globalId="UUID_f2ed94b4-7c23-4b8d-94e7-a6db226d7301">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>Flow side 2 m3/s</documentation>
            </variable>
            <variable name="Ts" globalId="UUID_a2fb5259-4aef-442b-b7f9-a64be0582269">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="0.1"/>
              </initialValue>
              <documentation>sample time</documentation>
            </variable>
            <variable name="U" globalId="UUID_99a47678-2f28-4b70-b04a-df844b11f0a0">
              <type>
                <REAL/>
              </type>
              <documentation>thermal conductivity[W/K]</documentation>
            </variable>
          </inputVars>
          <outputVars name="varGroup_e821" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="Temperature1_Out" globalId="UUID_d67500a0-48a5-4290-a09d-723797172f57">
              <type>
                <REAL/>
              </type>
              </variable>
            <variable name="Temperature2_Out" globalId="UUID_8cbf8b1b-d3b2-4af3-9c08-7af858779415">
              <type>
                <REAL/>
              </type>
              </variable>
          </outputVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">if NOT isInitialized then&#13;
    isInitialized := true;&#13;
    FOR index := 0 TO numberOfTanks DO&#13;
        T1_k[index] := Temperature2_In;&#13;
        T2_k[index] := Temperature2_In;&#13;
    END_FOR;&#13;
    dens := density(T1_k[0]);&#13;
    heatCap := heatCapacity(T1_k[0]);&#13;
    a1 := alpha(q:=q1, Ts:=Ts, V:=Volume1)*T1_k[0];&#13;
    b1 := beta(U:=U, Ts:=Ts, V:=Volume1, Temperature:=T1_k[1], q:=q1)*T1_k[1];&#13;
    o1 := omega(U:=U, Ts:=Ts, V:=Volume1, Temperature:=T1_k[1])*T2_k[40];&#13;
        &#13;
    t1k1 := a1+b1+o1;&#13;
END_IF;&#13;
&#13;
T1_k[0] := Temperature1_In;&#13;
T2_k[0] := Temperature2_In;&#13;
FOR index := 1 TO numberOfTanks DO&#13;
    T1_k1[index] := alpha(q:=q1, Ts:=Ts, V:=Volume1)*T1_k[index-1]&#13;
        +beta(U:=U, Ts:=Ts, V:=Volume1, Temperature:=T1_k[index], q:=q1)*T1_k[index]&#13;
        +omega(U:=U, Ts:=Ts, V:=Volume1, Temperature:=T1_k[index])*T2_k[numberOfTanks-index+1];&#13;
    T2_k1[index] := alpha(q:=q2, Ts:=Ts, V:=Volume2)*T2_k[index-1]&#13;
        +beta(U:=U, Ts:=Ts, V:=Volume2, Temperature:=T2_k[index], q:=q2)*T2_k[index]&#13;
        +omega(U:=U, Ts:=Ts, V:=Volume2, Temperature:=T2_k[index])*T1_k[numberOfTanks-index+1];&#13;
END_FOR;&#13;
&#13;
Temperature1_Out := T1_k[numberOfTanks];&#13;
Temperature2_Out := T2_k[numberOfTanks];&#13;
&#13;
(* Move next step into current step *)&#13;
T1_k := T1_k1;&#13;
T2_k := T2_k1;&#13;
</xhtml:p>
          </ST>
        </body>
        <documentation>This is a heat exchanger FB</documentation>
      </pou>
      <pou name="beta" pouType="function" globalId="fcbde407-d48a-4d96-ae7f-69e39e9ef95e">
        <interface>
          <returnType>
            <REAL/>
          </returnType>
          <inputVars name="varGroup_44a5" constant="false" retain="false" nonretain="false" persistent="false" nonpersistent="false">
            <variable name="U" globalId="25cd8c98-9d1d-4fe5-9898-98c1e0729b2f">
              <type>
                <REAL/>
              </type>
              <documentation>thermal conductivity</documentation>
            </variable>
            <variable name="Ts" globalId="f7166bfb-603b-4265-8110-e54277e0e05e">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="0.1"/>
              </initialValue>
              <documentation>sample time</documentation>
            </variable>
            <variable name="V" globalId="65de36df-9d47-44fb-9cac-3cc70b544099">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="1.0"/>
              </initialValue>
              <documentation>Volume</documentation>
            </variable>
            <variable name="Temperature" globalId="18635a09-ec8d-4f74-b863-73a2a50909e1">
              <type>
                <REAL/>
              </type>
              <initialValue repetitionValue="1">
                <simpleValue value="20.0"/>
              </initialValue>
              <documentation>temperature</documentation>
            </variable>
            <variable name="q" globalId="UUID_435863d3-f504-4aab-87c5-a818b32c713d">
              <type>
                <REAL/>
              </type>
              <documentation>flow</documentation>
            </variable>
          </inputVars>
        </interface>
        <body>
          <ST>
            <xhtml:p xmlns:xhtml="http://www.w3.org/1999/xhtml">beta := 1.0 - omega(U:=U, Ts:=Ts, V:=V,Temperature:=Temperature) - alpha(q:=q, Ts:=Ts, V:=V);</xhtml:p>
          </ST>
        </body>
        </pou>
    </pous>
  </types>
  <instances>
    <configurations>
      <configuration name="config" globalId="5383f879-0adc-4202-9f7a-7140b50c7a55">
        <resource name="resource1">
          <task name="task0" interval="T#100ms" priority="0">
            <pouInstance name="instance0" typeName="program0"/>
          </task>
        </resource>
      </configuration>
    </configurations>
  </instances>
  <addData>
    <data name="modbus">{'name': 'modbus', 'configs': []}</data>
    <data name="PROJECT_DOCS_ENSURED">true</data>
    <data name="runtimeId">ecaa8542-5873-4240-82a4-33b4cce01838</data>
    <data name="driver_5325ad15-44b8-4771-95b6-560f9fa45d3f">{'name': 'modbus', 'configs': [{'clients': [{'confnode': {'Remote_IP_Address': 'localhost', 'Configuration_Name': 'Modbus TCP Client 96c31d0963', 'Remote_Port_Number': 502, 'Request_Delay_in_ms': 0, 'Invocation_Rate_in_ms': 100}, 'requests': [{'symbols': [{'confnode': {'address': '%MW0.0.0.0'}, 'baseconfnode': {'Name': 'current', 'IEC_Channel': 0}}, {'confnode': {'address': '%MW0.0.0.1'}, 'baseconfnode': {'Name': 'speed', 'IEC_Channel': 1}}, {'confnode': {'address': '%MW0.0.0.2'}, 'baseconfnode': {'Name': 'torque', 'IEC_Channel': 2}}], 'confnode': {'SlaveID': 1, 'Function': '03 - Read Holding Registers', 'Start_Address': 0, 'Timeout_in_ms': 30, 'Nr_of_Channels': 3, 'Write_on_change': False}, 'baseconfnode': {'Name': 'analogSignals', 'IEC_Channel': 0}}], 'baseconfnode': {'Name': 'motor1', 'IEC_Channel': 0}}], 'servers': [], 'confnode': {'MaxRemoteTCPclients': 3}, 'baseconfnode': {'Name': 'modbus_0', 'IEC_Channel': 0}}], 'globalId': '5325ad15-44b8-4771-95b6-560f9fa45d3f'}</data>
  </addData>
</project>
If you’re not already there, switch to the projects tab in the app’s main navigation. While empty at first, you’ll see a list of all your existing projects within your organization to which you have at least viewing permission. To import an existing project, hit the button and select the XML project file you’ve just downloaded. A successful import will take you to the editor - your main user interface for programming, managing and deploying control logic to your virtual PLC (vPLC). OTee Import Light You can use this demo project to make yourself familiar with the editor and the various building blocks that together make a control system project in IEC 61131. You’ll also find detailed explanations on all things project in the OTee User Documentation. But for the sake of this quick start guide, let’s jump to the next step and get the project deployed to your very own virtual PLC.