Loop Check vs Calibration – What Most Technicians Get Wrong

A common field confusion that leads to wasted hours and wrong replacements.

Loop Check Verifies Wiring

• Checks PLC scaling
• Confirms signal path
• Does NOT verify sensor accuracy

Calibration Verifies Accuracy

• Applies known physical input
• Adjusts zero and span
• Does NOT verify PLC scaling

Common Mistake

Technician calibrates transmitter. Calibration passes. Reading still wrong in control room.

Root cause? PLC scaling error.

👉 Detailed technical guide: Loop Check vs Bench Calibration – Full Guide