Iec 612982 -

Before testing begins, the device must be installed according to the manufacturer's instructions. A "warm-up" period is required to ensure the device reaches thermal equilibrium and electronic stability.

Confusion often arises because several IEC standards deal with industrial instruments. Here is a clear differentiation: iec 612982

| Standard | Primary Focus | Key Question It Answers | | :--- | :--- | :--- | | IEC 61298 | Performance testing | "How accurate, repeatable, and stable is this device?" | | IEC 61508 | Functional safety | "Will this device fail safely if something breaks?" | | IEC 61326 | EMC (Electromagnetic compatibility) | "Does nearby radio noise or a lightning strike affect it?" | | IEC 60529 | Ingress protection (IP rating) | "Can dust or water get inside?" | Before testing begins, the device must be installed

Note: A device can be IEC 61298-tested (accurate) but not safe (IEC 61508). Conversely, a safety-certified transmitter can have poor accuracy—but that is usually unacceptable. But Vendor B's data sheet includes statements like:

You are specifying 200 pressure transmitters. Two vendors provide data sheets:

But Vendor B's data sheet includes statements like: "Tested according to IEC 61298-1 through -5. Reference accuracy: ±0.1% at 20°C. Additional temperature error: ±0.02% per 10°C. Long-term drift: 0.1% per year." Vendor A simply says "high accuracy."

Choose Vendor B. Why? Because you know exactly how the instrument will behave in your plant where summer temperatures hit 45°C. Vendor A's vague claim is unverifiable.