Mode Selection Wire
A hardware-level selection method that determines the working characteristic of the device by whether a wire is connected or not, instead of a menu or a key combination. When the connection is made one behaviour applies, when it is left free the other applies. On the AXI HCT402, connecting the blue wire to negative enables Soft mode.
On the electronics side this is the reading of the state of an input terminal on the board; when the terminal is free it sits at one level through an internal resistor, and when it is connected to chassis it is pulled to the other level. The board reads this state at power-up or continuously and selects the operating profile.
- Persistence: the selection depends on a physical connection; the mode does not change even if power is cut or the board resets.
- Lower risk of misuse: the operator cannot change the mode accidentally by pressing a key, the decision stays with the person doing the installation.
- Convenience in the field: it needs no display, menu or manual; changing the mode is a matter of disconnecting and reconnecting a single terminal.
The point to watch during installation is the insulation of this terminal. If it is to be left free, insulate the end; a wire that rubs against and touches the chassis changes the mode without you noticing and produces the complaint "the device is behaving differently today". Marking the wire and noting it on the wiring diagram prevents confusion at later servicing.
The context where this term is used: Converting a tractor hydraulic lever to electronic control