Sandel ST3400H HeliTAWS, Installation Manual

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When the Radalt is lower than the MINS setting a MINS discrete output is activated and an
audio callout “MINIMUMS” occurs.
When the Radar Altimeter is not configured, the MINS setting is retained on the display for
use as a visual reference by the pilot. The MINS discrete and callout will be disabled.
The MINS setting knob on the front panel has a push button function. This operates the
momentary discrete on J3, RADALT TEST.
3.5 Glideslope
This input provides the GPWS mode-5 glideslope alert. ARINC 429 or low level analog
inputs for Glideslope deviation, Glideslope flag status, and Localizer and Localizer Flag are
provided.
An additional discrete input is available for Back Course from the HSI, which acts to disable
Glideslope alerting while on a Back Course approach.
3.6 Air Data Computer
Airdata input is recommended. ARINC 429 airdata is supported as well as analog pressure
altitude. Use of analog pressure altitude requires ST3400H with MOD-1 installed per SIL
3400H-01.
3.7 Traffic
The ST3400H supports Traffic input via single ARINC 429 input. Traffic data is overlaid on
terrain.
Some traffic processors require remote switches. See Traffic interface drawings in this manual
for these requirements.
3.8 Landing Gear
The ST3400 has provisions on J-1 for Gear Down input discrete to indicate that the gear is in
the “DOWN” position for helicopters equipped with retractable landing gear.
The configuration is performed in the Maintenance Menu pages given in the Setup Procedures
section of this manual. If the system is installed in a helicopter without retractable landing
gear, select “NONE” on maintenance page configuration item.
3.9 External Switches and Annunciators
All external switches and annunciators are optional.
External switches are momentary contact OPEN/GND, normally open.
External annunciators, if used, must be properly labeled and colored.
82046-IM-K ST3400H INSTALLATION MANUAL Page 3-2