Connect the vacuum inlet port on the rear of the KI 256 to the aircraft vacuum regulator output. Use flexible, FAA-approved rubber vacuum hoses.
The installation must be performed by or supervised by an authorized avionics technician or FAA-certified mechanic.
The BendixKing KI 256 Go to product viewer dialog for this item. ki 256 installation manual
Ensure the pneumatic filter upstream is pristine; micro-particulates entering the gyro chamber will ruin the internal rotors. Electrical Wiring & Pinout Configurations
The KI 256 contains a . Never apply power while the unit is unmounted or in a non-level aircraft attitude. This can topple the gyro and cause immediate failure. Connect the vacuum inlet port on the rear
| Pin | Function | Wire AWG | Notes | |-----|----------|----------|-------| | A | +28 VDC (Gyro motor) | 22 | Switched by gyro circuit breaker | | B | DC Ground | 22 | Return for gyro motor & electronics | | C | +28 VDC (Flight Director logic) | 24 | Optional, from FD computer | | D | Pitch command (analog ±6V) | 24 | Shield to pin E at source | | E | Pitch command return | 24 | Shield drain ground at computer | | F | Roll command (analog ±6V) | 24 | Shield to pin H at source | | H | Roll command return | 24 | Shield drain ground at computer | | J | Backlight Hi | 22 | 5V AC/DC max | | K | Backlight Lo | 22 | Return | | L | Instrument ground | 22 | Connect to avionics ground bus |
Electrical connections are made via a rear-mounted rectangular Amphenol connector. The wiring harness carries flight director commands, autopilot pick-off voltages, and lighting power. Primary Pinout Assignments Pin Letter/Number Function Description Signal Type / Specifications Pitch Common Autopilot Reference Ground Pin B Pitch Signal Out Analog Voltage (Pitch Attitude) Pin C Roll Common Autopilot Reference Ground Pin D Roll Signal Out Analog Voltage (Roll Attitude) Pin E 26 VAC Gyro Excitation (H) 400 Hz Reference Input Pin F 26 VAC Gyro Excitation (C) 400 Hz Reference Return Pin M Panel Lighting Power 5V, 14V, or 28V (Model Dependent) Pin N Panel Lighting Ground Airframe Ground Wiring Best Practices: The BendixKing KI 256 Go to product viewer
The BendixKing KI 256 Flight Command Indicator is typically documented within the installation manuals of the flight control systems it serves, rather than as a standalone installation manual. Primary Manual Sources KFC 200 System Installation Manual : The KI 256 is a primary component of the BendixKing KFC 200