Signal Hunter
← FIELD MANUAL
🎯 SIGNAL HUNTER
// The 4–20mA Detective Game — Dextrose Plant, Tank 3
📋 Your Mission

Tank 3's level transmitter is sending bad data to the control room.

Problem:

• Control room shows: 75% full

• Sight glass shows: 45% full

⚠️ Bad data = Bad decisions = Ruined batch

🧰 Your Toolbox
🔌 Multimeter
🔧 Screwdriver
🚰 Vent/drain valves
🧠 Your brain
❤️ 3Lives
⭐ 0Score
❤️ 3Lives
⭐ 0Score
// Round 1 — First Check
🔍 Where do you check first?

What you know:

• Transmitter type: Differential Pressure (DP)

• Signal range: 4–20mA  (4 = empty, 20 = full)

• Expected signal at 45%: ~11.2mA

• Control room reading: 75% (~16.8mA)

❤️ 3Lives
⭐ 0Score
// Round 2 — Root Cause
🧠 Signal is real. What's feeding it bad info?

What you found:

✓ 16.8mA confirmed at transmitter terminals

✓ Not a wiring issue — signal is clean

✓ Transmitter IS the source of bad data

Now find WHY it's wrong...

❤️ 3Lives
⭐ 0Score
// Round 3 — The Fix
🔧 How do you fix it without shutting down?

The challenge:

• Batch is running — can't stop production

• Need accurate level reading NOW

• Choose wisely: wrong move = bigger problems

🏆 BATCH SAVED!
// Signal found. Root cause fixed. Production continues.
450 Final Score
🧠 What You Learned
💡 Key Takeaways
✓ 4–20mA loop: Check signal at source first — not the DCS
✓ DP transmitters: Impulse lines are the weak point in dextrose service
✓ Dextrose plants: Sweet + wet = eventually clogged. It WILL happen again.
✓ Surgeon vs parts-swapper: Fix the root cause, not the symptom
💥 BATCH RUINED
// Too many wrong moves. Out of time.
0 Final Score
What went wrong

Too many wrong moves cost you time. In the field that means:

• Overcooked batch — product loss
• Wasted ingredients and energy
• Lost production time
• Cleanup nightmare
💡 Pro Tip

Systematic troubleshooting beats guessing. Check the signal at source first, then work upstream to find what's feeding it bad data.