PRESSURE AND TEMPERATURE MONITORING - DESCRIPTION AND OPERATION

** ON A/C NOT FOR ALL

1. General

Component Location - Pylon ** ON A/C NOT FOR ALL

Two pressure sensors, one Control Temperature Sensor (CTS) and to Bleed-Air Monitoring Computers (BMC1, 1HA1 and BMC2, 1HA2) monitor the pressure and the temperature of the engine bleed air.

** ON A/C NOT FOR ALL

2. Component Location

Component Location - Pylon ** ON A/C NOT FOR ALL

Component Location - Avionics Compartment ** ON A/C NOT FOR ALL

FIN	FUNCTIONAL DESIGNATION	PANEL	ZONE	ATA REF
** ON A/C NOT FOR ALL
1HA1	BMC-1	95VU	121	36-11-34
1HA2	BMC-2	96VU	122	36-11-34
6HA1	SENSOR-EXCHANGER OUT TEMP, ENG 1		415	36-11-17
6HA2	SENSOR-EXCHANGER OUT TEMP, ENG 2		425	36-11-17
7HA1	XDCR-BLEED TRANSFER PRESS, ENG 1		471	36-11-15
7HA2	XDCR-BLEED TRANSFER PRESS, ENG 2		481	36-11-15
8HA1	XDCR-BLEED REGULATED PRESS, ENG 1		471	36-11-16
8HA2	XDCR-BLEED REGULATED PRESS, ENG 2		481	36-11-16

** ON A/C NOT FOR ALL

3. -

Component Installation ** ON A/C NOT FOR ALL

Two pressure sensors are installed on a bracket in each pylon.
They are similar but their functions are different:

The pressure sensor 7HA1(2) is used to measure the transferred pressure which is the pressure between the bleed pressure regulator valve and the HP bleed valve. The pressure sensor 7HA1(2) is electrically connected to the BMC 1(2) for monitoring purpose. A sensing line connects the pressure sensor 7HA1(2) to the pneumatic duct downstream of the HP bleed valve.
The pressure sensor 8HA1(2) is used to measure the regulated pressure. The pressure sensor 8HA1(2) is connected with a sensing line to the pneumatic duct downstream of the bleed pressure regulator valve. This sensor is electrically connected to the BMC 1(2) for monitoring/indication of the system parameters.

A temperature sensor 6HA1(2) is installed downstream of the precooler. It is installed in the elbow of the pneumatic duct in the left (right) pylon. An electrical cable connects the sensor to the BMC.

** ON A/C NOT FOR ALL

4. Component Description

Pressure sensor and Control Temperature Sensor ** ON A/C NOT FOR ALL

** ON A/C NOT FOR ALL

5. Power Supply

Monitoring - Electrical Schematic ** ON A/C NOT FOR ALL

-------------------------------------------------------------------------------

BUSBAR VOLTAGE FUNCTIONS ATA NO.

AND POWER

SUPPLY

-------------------------------------------------------------------------------

801PP 28 VDC ESS Power Supply to Pressure Sensor Eng 1 36-21-00

202PP 28 VDC NORM Power Supply to Pressure Sensor Eng 2 36-21-00

** ON A/C NOT FOR ALL

6. Operation

Component Location - Pylon ** ON A/C NOT FOR ALL

Component Location - Avionics Compartment ** ON A/C NOT FOR ALL

Component Installation ** ON A/C NOT FOR ALL

Component Location - Cockpit ** ON A/C NOT FOR ALL

Indication - Lower Ecam Display Unit ** ON A/C NOT FOR ALL

A. Pressure Indication
The two pressure sensors give the:

Transferred relative static pressure (downstream of the HP valve)
Regulated relative static pressure (downstream of the PRV).

They transmit signals to the connected BMCs which monitor the pressure. The BMC prepares the data for the Built-In Test Equipment (BITE) (analysis of the maintenance of the HPV and the PRV). The BMCs also send ARINC data to the SDACs which use it for ECAM display. The lower ECAM display unit shows the pressure on the BLEED page in green. If the pressure is too high, it is shown in amber.

(1) The main functions of the bleed transferred pressure sensor 7HA1(2) are:

To give the HP VALVE FAULT ECAM warning if the transferred pressure is less than 23 psi during more than 15 sec. and if the HP bleed valve is fully closed.
To give the AIR ENG ABNORMAL PRESS ECAM warning.

If the sensor 7HA1(2) is defective, there is no effect on the ECAM bleed pressure indication.

(2) The main functions of the bleed regulated pressure sensor 8HA1(2) are:

To give the AIR ENG BLEED FAULT ECAM warning if the regulated pressure is more than 57 psi during more than 15 sec. and if the bleed-pressure regulator valve is not fully closed.
To give the WING ANTI ICE INOP ECAM status (that comes from the zone controller through the BMC 1 or 2) when there is not sufficient bleed air to supply the wing anti-ice system, (when the regulated pressure is out of the 12/60 psi range).
To give the AIR ENG ABNORMAL PRESS ECAM warning if the regulated pressure is less than 23 psi and if the transferred pressure is in the 12/38 psi range.
To transmit the regulated pressure data for show on the BLEED ECAM page.

B. Temperature Indication
A Temperature sensor is installed at the precooler outlet to sense the temperature. It has two platinum resistance wires. Each wire transmits a signal to the BMCs. The BMCs monitor the temperature of the system.
The BMCs prepare the data for the Built-In Test Equipment (BITE). The BMCs also send ARINC data to the SDACs for ECAM display information. The lower ECAM display unit shows the temperature on the BLEED page in green. If the temperature is too high, it is shown in amber.

[Rev.10 from 2021] 2026.04.01 01:16:15 UTC