Industrial Engineer · phase 12 of 16
Preset Speed
Stored frequency or speed reference selected by digital inputs or network commands.
The Explain card
- Plain English
- A preset speed is a fixed reference stored in the drive and selected by a digital input or a network bit. Several presets can be defined and chosen in combination.
- Example
- Three inputs select up to seven presets. A washdown mode selects preset one at 15 hertz, normal production selects preset two at 50, and no analog signal is needed.
- Why it matters
- Presets replace a potentiometer or an analog output with a couple of dry contacts, which is cheaper and immune to noise. They are also a classic place for a mystery, since a stuck input quietly selects a speed nobody remembers setting.
- Hook
- Speeds on a switch, with no wire that can drift.
Where it sits in the deck
Phase 12: VFD Commands, References, and Stopping
Starting, referencing and stopping, including the several very different things a drive can mean by the word stop.
