Fault Phenomenon: Hongda HBT120 metering is accurate when cold. With the scale under direct sunlight (operating temperature), the load cell drifts, data jumps, and metering becomes inaccurate.

Troubleshooting Process:
– Checked scale support: support secure.
– Checked sensor wiring: wiring intact.
– Checked instrument settings: settings correct.
– Measured sensor output millivolts at operating temperature: found significant zero-point drift.

Root Cause: The strain gauge on the load cell experiences coefficient change due to heat, causing signal drift.

Required Parts: Load cell assembly.