SIGNA MR355 / SIGNA MR360
Service Manual
5856356-3EN Revision 5.0
Basic Service Documentation. Copyright General Electric Company.
Object ID: 00000018WIA30E35F20GYZ
Topic ID: id_13106998 Version: 1.2
Date: Jul 6, 2019 12:17:31 AM

STIF Board SRI PAC Fiber Optic Checks

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	-	-	-

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
Fiber Optic Light Meter Kit	1	-	46-317830G1	-

Table 3. Safety

Warning

POSSIBLE EYE INJURY!

OBSERVING THE TRANSMITTER OUTPUT POWER UNDER MAGNIFICATION MAY CAUSE INJURY TO THE EYE.

WHEN VIEWING WITH THE UNAIDED EYE, OR NORMAL EYE GLASSES, THE INFRARED OUTPUT IS RADIOLOGICALLY SAFE. HOWEVER, WHEN VIEWED UNDER MAGNIFICATION, PRECAUTION SHOULD BE TAKEN TO AVOID EXCEEDING THE LIMITS RECOMMENDED IN ANSI Z136.1 - 1981.

Warning

FERROUS MATERIAL HAZARD!!

power adapter or battery in Fiber Optic meter kit CONTAINS PARTS MADE WITH FERROUS COMPONENTS. HOLDING THIS ASSEMBLY TOO CLOSE TO THE MAGNET BORE WILL FORCIBLY ATTRACT IT TO THE MAGNET.

TO PREVENT POSSIBLE BODILY INJURY, OR DAMAGE TO COMPONENTS, NOT MOVING IT IN THE MAGNETIC FIELD MORE THAN IS NECESSARY.

Table 4. Required conditions
Condition	Reference	Effectivity
Fiber Optic Light Meter Kit Parts Break Down.	-	-

About this task

This procedure describes how to turn on the fiber optic drivers in a Signa system. Software output control is provided for the HFBR-1522 drivers (plastic cable) and the HFBR-1414 drivers (glass cable) on the STIF Board in the CAM-Lite Chassis, the HFBR-1522s (plastic cable) on the PAC and the SRI, and the HFBR-1522 drivers (plastic cable) on the MDS peripherals.

STIF BOARD, SRI, PAC FIBER OPTIC CHECKS

Procedure

Access to the STIF Board and disconnect the 7 fiber optic cables from J11, J12, J13, J14, J15, J16, J19, J18, J19 of STIF Board according to the Figure 1.
The Fiber Optic Test can be selected from the Diagnostics menu. The drivers on the STIF card (See Figure 1) remain on until the Fiber Optic Test is canceled. The drivers on the link remain on until the test is canceled, or a break occurs in the link upstream from the device being tested.

Figure 1. STIF CARD LOCATION

Fiber Optic Power Level Measurement

Procedure

To turn on the HFBR-1522 drivers on the STIF Board and the HFBR-1522 drivers on the FRI fiber optics and STIF-SRI fiber optics, go to the Service Desktop on the host computer and start the Service Browser if it’s not already running by clicking the Service Browser button on the diagnostics menu on the left side of the screen. See Figure 2.

Figure 2. STARTING FIBER OPTIC TESTS
This test illuminates the fiber optic transmitters on the STIF board to allow testing their intensity. The LEDs illuminated are SRI Reset, SRI Tx, Grad X,Y,Z Clock, PAC Tx, and MDS TX. They will continue to be illuminated until the Stop button is pressed.
Remove protective cover and install the appropriate adapter (46-320033G1 for plastic cables; FOA-32 for glass cables) onto the fiber optic meter. Plug test cable (1/2 m for plastic (46-307564P4), 1 m for glass (46-307584P3)) onto the adapter. See Figure 3.

Figure 3. FIBER OPTIC MEASUREMENT CONFIGURATION
Use the on/off button to turn on the EXFO fiber optic meter. Make sure the meter is on 660 calibration for plastic links and 820 calibration for glass links. Use the λ Select button to alternate between wavelength values displayed on the meter LCD display. Use the dBm/W button to select dBm unit scale on the meter LCD display.
Disconnect system cable from transmitter (gray fiber optic connector) under test. Connect the test cable into the transmitter under test.

Note:
Cable damage possibility. Disconnecting the fiber optic cables by pulling on the cable can damage the cable/connector. Use the connector to disconnect cables.

Note:
The fiber optic connectors are a latching type connector. For the plastic cable connectors, press on the latch to release. For the glass cable connectors, press in on outer connector shell and rotate a quarter turn.
Measure transmitter output through test cable with EXFO fiber optic meter. Compare this value with specification. See Figure 4 . If value is out of spec, there is a problem. It could be a power supply problem, transmitter problem, or functional problem with board. Do not proceed until this value is within spec.

Figure 4. 1.5T FIBER OPTIC POWER LEVELS

Note:
The fiber optic connectors are a latching type connector. For the plastic cable connectors, press on the latch to release. For the glass cable connectors, press on the outer connector shell and rotate a quarter turn.
Disconnect test cable from the transmitter under test and reconnect system cable to transmitter.
Disconnect test cable from EXFO fiber optic meter.
Disconnect far end of system cable from receiver (blue fiber optic connector; gray for some) and connect system cable to meter adapter.
Note:
For the optical cable form PAC (the cable connected to J18/J19 at STIF), just inspect that the signal light can be seen from the cable end.

Measure optical output from system cable. Compare this value with specification. If this value is out of spec and the transmitter output was within spec, there is a cable routing issue or a damaged cable. Check cable for kinks, tight radius bends, damaged or poorly polished connectors, etc.
Repeat this procedure for each link that requires testing.

TEST SPECIFICATIONS

About this task

The following data characterize fiber optic power levels in a Signa system. Typical data were obtained from a limited sample of systems. Typical values may cover a wide range due to the effects of cable routing, connecting, and cable length which may vary from system to system. Minimum values, however, are absolute, and will be the same for fixed sites, mobiles, and T/R(s).

Procedure

Plastic Data Links (AMP fiber 501232-5 or 501336-1 with HP versatile link connectors and 660 nm HFBR-1522/ HFBR-2522 transmitter/receiver pair):

STIF J16 to SRI J11; STIF J17 to SRI J13; SRI J12 to STIF J15;

Nonmodulated HFBR-1522 transmitter output through 1/2 m test cable:

Typical: -8.5 dBm

Minimum: -11.2 dBm
Nonmodulated HFBR-1522 transmitter output through 147 ft cable:

Typical: -21.5 dBm

Minimum: -23.0 dBm

Gradient (glass) Data Links: (AMP fiber 502083-1 with ST type connectors and 820 nm HFBR-1414/HFBR-2416 transmitter/receiver pair)

STIF J14 to GP J2; STIF J13 to GP J3; STIF J12 to GP J4; STIF J11 to GP J1:

Nonmodulated HFBR-1414 transmitter output through 1 m test cable:

Typical: -15 dBm

Minimum: -18.0 dBm
Nonmodulated HFBR-2416 transmitter output through 46 ft glass cable:

Typical: -16 dBm

Minimum: -20.0 dBm

Note:

Do not observe the light directory. Use white paper and reflect the beam to observe.

STIF J18 to PAC J9; STIF J19 to PAC J10;

Finalization

Procedure

Turn off the fiber optic meter. Disconnect all kit components used in measurement scheme and return to kit. See Figure 5.

Figure 5. Fiber Fiber Optic Light Meter Kit
Restore all system fiber optic cables and components to original configuration.