(f)
On AT ALL, check that GS 3, VOR 3 AC, VOR 3 DC, ALT ADI 1, ALT ADI 2, ALT HSI 1, ALT HSI 2, CAPT ILS BUFFER 1 and F/O ILS BUFFER 1 circuit breakers on overhead lightplate circuit breaker panel P126 are closed.
(g)
On XA ALL EXCEPT AT airplanes, set the VOR/ILS transfer switch to the center position (CAPT 1 F/O 2).
(h)
On AT ALL, position captain's VOR/ILS 3 transfer switch to NORM.
(i)
On AT ALL, position captain's and F/O's DEV transfer switches to NORM.
(j)
Set captain's and first officer's VOR/ILS-INS transfer switches to VOR/ILS.
(k)
Turn on VOR/ILS navigation systems using applicable controls on VHF NAV control panels.
(2) Shutdown Procedure
(a)
Turn off VOR/ILS navigation systems.
(b)
Remove electrical power if no longer required (Ref 24-22-00).
F. Functional Description, Relay Control (Fig. 4) (XA ALL EXCEPT AT airplanes)
EFFECTIVITY
AZ ALL
AT ALL
IB ALL CONFIG 2 SN ALL 01 Page 21 Oct 25/97
34-31-00
(1)
The selection of the two VOR/ILS receivers being used is controlled by the captain's VOR/ILS transfer switch which, in turn control the positions of the captain's and first officer's VOR/ILS A transfer relays (and VOR/ILS B transfer relays on AZ 221-299; SN 351-399; IB 406-499). With the VOR/ILS transfer switch in the normal position (CAPT 1, F/O 2) the relays are set to provide data to the captain from receiver No. 1 and to the first officer from receiver No. 2.
(2)
If, for example, the captain's VOR/ILS transfer switch is set to position 3, 28-volt dc power will be applied through the switch to the stepping solenoid of the captain's VOR/ILS A transfer relay causing the relay to switch from the No. 1 to the No. 3 position. While the captain's VOR/ILS A transfer relay is in the alternate (No. 3) position the dc path to the first officer's VOR/ILS A transfer relay solenoid is broken, thus preventing both pilots from selecting the No. 3 receiver simultaneously.
(3)
The VOR/ILS transfer switch annunciator provides an indication of the VOR/ILS receivers being used by the pilots.
G. Functional Description, Relay Control (Fig. 4) (AT ALL)
(1)
The selection of the two VOR/ILS receivers being used is controlled by the captain's VOR/ILS 3 transfer switch which, in turn control the positions of the captain's and first officer's VOR/ILS A and B transfer relays. With the VOR/ILS 3 transfer switch in the NORM position the relays are set to provide data to the captain from receiver No. 1 and to the first officer from receiver No. 2.
(2)
If, for example, the captain's VOR/ILS 3 transfer switch is set to CAPT 3 position, 28-volt dc power will be applied through the switch and the normal contacts of the first officer's VOR/ILS A transfer relay to the stepping solenoid of the captain's VOR/ILS A and B transfer relays causing the relays to switch from the No. 1 to the No. 3 (alternate) position. While the captain's VOR/ILS A transfer relay is in the alternate position the dc path to the first officer's VOR/ILS A and B transfer relay solenoids is broken, thus preventing both pilots from selecting the No. 3 receiver simultaneously.
(3)
The selection of the VOR/ILS receiver to drive the ADI and HSI VOR/LOC and glide slope deviation and flag warning displays is controlled by the captain's and first officer's DEV transfer switches. The switches control the captain's and first officer's deviation transfer relays in the same manner as the captain's VOR/ILS 3 switch control the VOR/ILS A and B transfer relays.
(4)
The DEV transfer switches enable both pilots to display data simultaneously from the same system. However, interlocking prevents a second transfer from taking place. In other words, if the captain's instruments are connected to the alternate system, the first officer's instruments cannot be transferred to the same alternate system and vice versa.
EFFECTIVITY
AZ ALL
AT ALL
IB ALL CONFIG 2 SN ALL 03 Page 22 Oct 25/97
34-31-00
(5)
Normal position of the captain's deviation transfer relay connects receiver No. 1 or 3 to the captain's instruments while normal position of the first officer's deviation transfer relay connects receiver No. 2 or 3 to the first officer's instruments.
(6)
When the first officer's DEV transfer switch is set to alternate position, the first officer's relay energizes momentarily and steps to the alternate position. This opens the interlock circuit for the captain's deviation transfer relay which must remain in the normal position until the first officer's deviation transfer circuits are returned to normal. Positioning the first officer's DEV switch back to NORM allows the captain's deviation transfer circuits to be switched to the alternate position for selecting either receiver 2 or 3 as the signal source for the captain's flight instrument displays.
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本文链接地址：747飞机维护手册AMM CHAPTER 34 - NAVIGATION 第34章导航2(12)
