EFFECTIVITY BEJ ALL 29-10-00
Page 36
D633W101-BEJ Sep 05/2002
777 AIRCRAFT MAINTENANCE MANUAL
MAIN HYDRAULIC SYSTEMS -ADU HEATERS
EFFECTIVITY BEJ ALL 29-10-00
Page 37
D633W101-BEJ Sep 05/2002
MAIN HYDRAULIC SYSTEMS -ADU HEATERS -FUNCTIONAL DESCRIPTION
General
The air drive unit (ADU) heaters operate automatically to keep the temperature of the ADU speed control components higher than freezing. This prevents icing in the ADU.
The HYDIM CL card controls the heaters for both ADUs. The P210 right power management panel supplies the electrical power to operate the heaters.
Functional Description
The HYDIM CL card sends a signal to the ELMS to operate the ADU heaters for any of these conditions:
*
Total air temperature is less than 2C (ADIRU input through the AIMS)
*
ADP C1 case drain temperature is less than 10C
*
ADP C2 case drain temperature is less than 10C
*
ADP C1 operational test (MAT test)
*
ADP C2 operational test (MAT test)
*
Heaters operational test (MAT test).
The ON signal goes to the ELMS electronics unit (EEU) in the P210 right power management panel. The EEU energizes heater relays to supply power to the ADU heaters and also to the RAT heater.
The heaters go off 30 minutes after the total air temperature goes above 2C and both ADP case drain temperatures are more than 10C. The heaters also go off 5 seconds after a RAT deployment.
ADU heater sensor relays send the ADU heater on/off condition to the HYDIM cards. The HYDIM cards use this to monitor for correct heater operation.
The ADU heater elements connect in series. A failure of a single element causes the failure of all the elements in the assembly.
EFFECTIVITY BEJ ALL 29-10-00
Page 38
D633W101-BEJ Sep 05/2002
MAIN HYDRAULIC SYSTEMS -ADU HEATERS -FUNCTIONAL DESCRIPTION
EFFECTIVITY BEJ ALL 29-10-00
Page 39
D633W101-BEJ Sep 05/2002
MAIN HYDRAULIC SYSTEMS -AC MOTOR PUMP (ACMP) PRESSURE AND CASE DRAIN FILTER MODULE
Purpose
The ACMP pressure and case drain filter module removes particles from the hydraulic fluid after the fluid leaves the ACMP. Transducers on or near the filter module send pressure and temperature signals to the HYDIM cards.
Physical Description
Each of the four ACMPs has its own pressure and case drain filter module. All of these modules are interchangeable.
Each filter module has these components:
*
Case drain filter
*
Pressure filter
*
Automatic filter bowl removal shutoff valve (not shown) (2)
*
Differential pressure indicators (red pop-up indicator)(2)
*
Check valves (2)
*
Pressure transducer (center system filter modules)
*
Temperature transducer.
Location
The filter module for the left hydraulic system is in the left aft engine strut fairing. The filter module for the right hydraulic system is in the right engine strut. You get access to these filter modules through the aft strut fairing doors on the right side of each engine strut.
The filter modules for the two center system ACMPs are in the right wheel well on the keelbeam.
Functional Description
Hydraulic pressure and case drain flow goes through the filters in the filter modules.
A temperature transducer in the case drain line sends temperature signals to the HYDIM cards. A pressure transducer in the pressure line sends pressure signals to the HYDIM cards.
Check valves prevent hydraulic backflow through the filter module.
Training Information Point
You can not clean the filters and use them again.
The red differential pressure indicator extends to show a clogged filter. Replace the filter and manually reset the indicator.
EFFECTIVITY BEJ ALL 29-10-00
Page 40
D633W101-BEJ Sep 05/2002
MAIN HYDRAULIC SYSTEMS -AC MOTOR PUMP (ACMP) PRESSURE AND CASE DRAIN FILTER MODULE
EFFECTIVITY BEJ ALL 29-10-00
Page 41
D633W101-BEJ Sep 05/2002
777 AIRCRAFT MAINTENANCE MANUAL
THIS PAGE IS INTENTIONALLY LEFT BLANK
29-10-00
Page 42 D633W101-BEJ Jan 05/2002
MAIN HYDRAULIC SYSTEMS -ADP AND EDP PRESSURE AND CASE DRAIN FILTER MODULES
Purpose
The pressure and case drain filter modules for the EDPs and the ADPs remove the particles from the hydraulic fluid after the fluid leaves the pumps. A pressure relief valve in the modules supplies system protection if pressure gets too high. 中國航空網 www.k6050.com 航空翻譯 www.aviation.cn 本文鏈接地址：777 AMM 飛機維護手冊 液壓 Hydraulic Power(12)
