DOC AIRBUS | AMM A320FPOWER INDICATING SYSTEM - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. General
The power indicating system includes the low rotor speed sensor (N1) and the high rotor speed sensor (N2).
** ON A/C NOT FOR ALL The power indicating system includes the low rotor speed sensor (N1) and the high rotor speed sensor (N2).
Power Indicating System2. Description
A. N1 Sensor
The low rotor speed sensor (N1) gives a redundant low rotor speed (N1) signal to the Electronic Engine Control (EEC). These speed signals are used for engine control (i.e. thrust setting) and vibration monitoring. The once-per-revolution signal is also used for the fan trim balance during maintenance. It is a two-channel magnetic reluctance sensor fitted on the fan hub with two bolts located on the n4 strut (i.e. 123 degree aft looking forward).
It is associated with a phonic wheel, the N1 speed sensor wheel, located at the rear of the n2 bearing, locked on the low pressure compressor shaft by a nut. This steel wheel features 29 high teeth (for speed measurement) and a single low tooth (for angular position measurement).
Signals from the N1 speed sensor are routed to the EEC by the channel A and the channel B electrical harnesses. Each connector is foolproofed (i.e. connector A can only be linked to EEC channel A).
The low rotor speed sensor (N1) gives a redundant low rotor speed (N1) signal to the Electronic Engine Control (EEC). These speed signals are used for engine control (i.e. thrust setting) and vibration monitoring. The once-per-revolution signal is also used for the fan trim balance during maintenance. It is a two-channel magnetic reluctance sensor fitted on the fan hub with two bolts located on the n4 strut (i.e. 123 degree aft looking forward).
It is associated with a phonic wheel, the N1 speed sensor wheel, located at the rear of the n2 bearing, locked on the low pressure compressor shaft by a nut. This steel wheel features 29 high teeth (for speed measurement) and a single low tooth (for angular position measurement).
Signals from the N1 speed sensor are routed to the EEC by the channel A and the channel B electrical harnesses. Each connector is foolproofed (i.e. connector A can only be linked to EEC channel A).
B. N2 Sensor
The N2 sensor gives a redundant high rotor speed (N2) signal to the EEC. These speed signals are used for engine control (i.e. thrust setting) and vibration monitoring.
The high rotor speed sensor, N2, is a two-channel magnetic reluctance sensor. It is fitted on the Transfer Gearbox (TGB) transfer tube, located on the accessory gearbox on the fan case.
It is associated with a phonic wheel, locked on one of the transfer gearbox shafts. This wheel features 19 teeth (for speed measurement).
The N2 sensor gives a redundant high rotor speed (N2) signal to the EEC. These speed signals are used for engine control (i.e. thrust setting) and vibration monitoring.
The high rotor speed sensor, N2, is a two-channel magnetic reluctance sensor. It is fitted on the Transfer Gearbox (TGB) transfer tube, located on the accessory gearbox on the fan case.
It is associated with a phonic wheel, locked on one of the transfer gearbox shafts. This wheel features 19 teeth (for speed measurement).