Industrial Engineer · phase 2 of 16
Resolution
Smallest input or output change an analog module can represent, commonly specified in bits or counts.
The Explain card
- Plain English
- Resolution is the smallest change an analog card can tell apart. More bits means more steps across the same range and therefore finer detail.
- Example
- A 12 bit card splits 0 to 10 V into 4096 steps of roughly two and a half millivolts. A 16 bit card splits the same range into 65536 steps.
- Why it matters
- A coarse card on a wide range hides small changes a control loop needs to see, so the loop hunts or never settles. Resolution says nothing about accuracy, though, and a card can resolve a thousandth of a volt while being off by a tenth.
- Hook
- How finely the ruler is marked, and nothing about how straight it is.
Where it sits in the deck
Phase 2: PLC I/O and Field Signals
Where the controller meets the machine: discrete and analog signals, the wiring conventions behind them, and the field devices that send them.
