Hamilton Jet HTX30, Product Manual

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HTX30 Product Manual Appendix
8-25
Output - Normal/backup:

(Refer throttle above)
Input - Warm-up:

blue ARROW provides indication if the engine is or should be limiting maximum RPM. For example,
during warm-up.

A switch contact to ground should be provided.

When the contacts are closed blue ARROW will be in warm-up mode.

If not used then this input should be left unconnected.

If the throttle is advanced beyond the warm-up level when in warm-up mode, a warning alarm will
sound.

Full throttle is still available if required.
Input - Local/remote:

blue Arrow supports local override. This allows electronic engines to be controlled from a local control
panel.

A switched contact to ground should be provided.

When the contact is closed, local mode is selected.

Local control disables gearbox control from the station control panel.

The system will report the current state of the gearbox.

When in local override, the engine should ignore throttle demand from the system.

If the engine implementation does not automatically ignore external throttle demand when in local
control, a relay contact should be fitted in the throttle demand line that will be open circuit when local
mode is selected.

When returning from local to remote (blue Arrow) control, the system will retain the gearbox state, and
return the throttle to idle.

Throttle levers must be moved to idle before normal throttle control is restored.
Input - RPM feedback

blue ARROW supports two types of RPM feedback.
Switched pulse feedback.
Voltage feedback.

Switched pulse feedback requires a contact closure to ground between 1 and 12 times every revolution.

Each contact closure should occur for 18 degrees of rotation and maximum speed should be less than
4500RPM

Voltage feedback requires a DC voltage proportional to the engine RPM.

An RPM sensor is integrated onto the jet unit.