PLC Gym
0 XP
Missions · Control room
Mission 88 · PRO

Write the batch record as it happens: PLC SCADA training exercise

Batch number, time in every phase, totals and the peak temperature, closed the moment the batch ends.

Make the reactor keep its own batch record. Number each batch, time every phase as it runs, keep the charged totals, the time on hold and the peak temperature, and close the record with its result when the batch ends, complete or aborted.

This mission is part of ProCreate a free account: every account gets a free Pro trial until 5 December.

No card. Nothing to pay. Nothing to cancel.

Official release: 5 December. Top the leaderboard on the day and win 3 months of Pro, plus 2 weeks of Pro to give a friend. 2nd place wins 4 weeks. 3rd place wins 2 weeks. Rules

  • Every Coaching lesson, from zero
  • Every mission and lesson, as you level up
  • A practical test for every title, with a certificate
  • Rewind any test, one scan at a time
  • Worked solutions when you're stuck
  • The code converter, as much as you like
The 3D batch reactor control this mission runs onPRO mission
How the test runs

A new batch starts a clean record

Test 1 of 3
Set by the testChecked by the testStep 8 of 8 · 5.3 s
Level
Advanced
Time
About 45 min
Reward
+650 XP
Rig
3D batch reactor control
Siemens editors
Ladder (LAD), SCL
Rockwell editors
Ladder, Structured Text
Beckhoff editors
Structured Text
Stage
46. SCADA 4: a batch record as it happens
Required behaviour

Write the batch record as it happens: what your code must do

The batch control is written and working. Write the record below it. A batch is in progress while State is 10 or 20: keep that in InBatch. When InBatch comes on, a new record starts: add 1 to BatchNo, set Result to 0, ReportReady to FALSE, every time to 0.0 and PeakTemp to Temp. While Run is on, add 0.02 each scan to the time of the phase in progress: TimeA in Phase 1, TimeB in 2, TimeHeat in 3, TimeReact in 4, TimeCool in 5, TimeDrain in 6. While State is 20, add 0.02 to TimeHeld instead. While InBatch is on, PeakTemp follows Temp upwards and never down, TotalA copies VolA and TotalB copies VolB. The batch ends when State reaches 40 or 30: set Result to 1 for complete or 2 for aborted, and ReportReady to TRUE. After that nothing in the record changes until the next batch starts. On the Operator screen tab, choose how the report writes a time, what it shows beside each value, and what an aborted batch gets.

New batch
InBatch comes on: BatchNo + 1, Result 0, ReportReady off, times 0, PeakTemp := Temp.
Times
0.02 a scan to the phase in progress while Run; to TimeHeld while State is 20.
End
State 40: Result 1. State 30: Result 2. Both set ReportReady, and the record stops.
Tag table

Write the batch record as it happens: inputs and outputs

Your program reads 9 inputs and sets 23 outputs. One more input drives the simulation or shows a reading, for you to test with. The names are the same in every maker’s editor.

TagData typeYour codeWhat it means on the machine
StartBOOLReadsAn input your code needsStart a batch
HoldBOOLReadsAn input your code needsHold the batch
RestartBOOLReadsAn input your code needsRestart a held batch
AbortBOOLReadsAn input your code needsAbort the batch
ResetBOOLReadsAn input your code needsReset to Idle
ChargeFlowREALReadsAn input your code needsCharge flowmeter, L/s
LevelREALReadsAn input your code needsContents, L
TempREALReadsAn input your code needsBatch temperature, °C
AgitatorRunningBOOLReadsAn input your code needsAgitator up to speed
CoolingFailBOOLNot neededFor testing or watching; your code can leave it outTry it: the cooling water fails
ValveABOOLWritesAn output your code setsCharge from tote A
ValveBBOOLWritesAn output your code setsCharge from tote B
AgitatorBOOLWritesAn output your code setsRun the agitator
SteamBOOLWritesAn output your code setsSteam to the jacket
CoolingBOOLWritesAn output your code setsCooling water to the jacket
DrainBOOLWritesAn output your code setsBottom outlet valve
RunLampBOOLWritesAn output your code setsState tower: Running
HeldLampBOOLWritesAn output your code setsState tower: Held
AbortLampBOOLWritesAn output your code setsState tower: Aborted
CompleteLampBOOLWritesAn output your code setsState tower: Complete
BatchNoINTWritesAn output your code setsRecord: batch number
ResultINTWritesAn output your code setsRecord: 0 in progress, 1 complete, 2 aborted
ReportReadyBOOLWritesAn output your code setsRecord: the batch has ended and its record is closed
TotalAREALWritesAn output your code setsRecord: A charged, L
TotalBREALWritesAn output your code setsRecord: B charged, L
TimeAREALWritesAn output your code setsRecord: seconds charging A
TimeBREALWritesAn output your code setsRecord: seconds charging B
TimeHeatREALWritesAn output your code setsRecord: seconds heating
TimeReactREALWritesAn output your code setsRecord: seconds reacting
TimeCoolREALWritesAn output your code setsRecord: seconds cooling
TimeDrainREALWritesAn output your code setsRecord: seconds discharging
TimeHeldREALWritesAn output your code setsRecord: seconds on hold
PeakTempREALWritesAn output your code setsRecord: highest temperature of the batch, °C

In Siemens SCL, write a block’s own tags with # in front, as TIA Portal does: #Start. Rockwell and TwinCAT use the name on its own: Start.

Automatic tests

Write the batch record as it happens: what the tests check

  1. Each Start begins a new record: BatchNo goes up by one and every value starts clean.
  2. Each phase's time counts only while that phase runs; time on hold is counted on its own.
  3. PeakTemp is the highest temperature of the batch; TotalA and TotalB are the litres charged.
  4. When the batch completes or aborts, Result says which, ReportReady comes on, and the record stops changing.
  5. The report writes times as minutes and seconds, shows each target beside its value, and gives an aborted batch a report too.
  1. Try it Use the buttons below the model and watch the rig respond.
  2. Test solution Every check runs on your code in one press.
  3. Rewind PRO If one fails, step back through it one scan at a time to see why.

Stuck on this mission? Ask the members in the Locker Room.

Why it matters

Where you’d see this on site

In a pharmaceutical or food plant, every batch leaves a record that quality staff review before the product is released. The SCADA collects it from the PLC the moment the batch ends.

A batch with no record can't be released, and a record written after the event can't be trusted. Either way a day's production is held or scrapped.

Where you'd find thisMake the batch, keep the reaction in hand, and stop safely at any moment

Chemical, pharma and food batch plants follow recipes in phases. Operators can hold a batch and restart it, or abort it; the controller must know exactly what is safe in every state. Some reactions release heat, and if cooling falls behind they run away.

  1. ChargeA, then B
  2. React80 °C for 30 sYou are here
  3. CoolTo 40 °C
  4. DischargeTo receiver
On a real site: places, parts and safety
  • Speciality chemicals and resins
  • Pharmaceutical and biotech batch suites
  • Food ingredients and flavours

Runaway reactions caused disasters such as Seveso (1976) and T2 Laboratories (2007). Real reactors have independent high-temperature trips and relief systems.

ISA-88 defines the state model used here, so operators everywhere know what Hold and Abort mean.

The sizes, timings and cutaways are teaching choices, not a drawing of any one real installation.

Keep going

Next on the road