S 012-043
(2)
Remove the WIU protective cover.
S 492-044
WARNING: USE A WRIST STRAP WITH A MINIMUM GROUNDING LEAD RESISTANCE OF
_______ 250 KILOHMS AND A MAXIMUM OF 1.5 MEGOHMS. USE OF A LOW RESISTANCE WRIST STRAP CAN CAUSE INJURY TO PERSONS IF A HIGH VOLTAGE SOURCE IS TOUCHED.
(3) Do these steps to do a test of the wrist strap resistance:
(a)
Use an ohmmeter to make sure the wrist strap assembly has a minimum resistance of 250 kilohms and a maximum of 1.5 megohms.
(b)
Put the wrist strap on your wrist.
(c)
Use an ohmmeter to make sure the resistance is less than 10 megohm.
S 862-058
(4) Connect the wrist strap into the ELECTROSTATIC GROUND JACK of the card file.
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MAINTENANCE MANUAL
S 492-059
CAUTION: THE GROUNDING LEAD ON THE WRIST STRAP MUST TOUCH THE
_______ SKIN TO GIVE THE PROTECTION THAT IS NECESSARY. FAILURE TO USE THE WRIST STRAP CORRECTLY CAN CAUSE DAMAGE TO THE ESDS PRINTED CIRCUIT BOARDS.
(5) Attach the wrist strap correctly on the person that will remove the printed circuit board.
S 012-055
CAUTION: DO NOT PERMIT CONTAMINATION IN THE WIU WHEN THE COVER IS OFF.
_______ MAKE SURE THAT YOU KEEP CONTAMINATION OR UNWANTED MATERIAL AWAY FROM THE WIU. MAKE SURE THAT OTHER PEOPLE THAT WORK AROUND THE WIU AREA KEEP UNWANTED MATERIAL OR CONTAMINATION AWAY FROM THE WIU. UNWANTED MATERIAL OR CONTAMINATION CAN CAUSE A MALFUNCTION IN THE WIU.
(6) Remove the WIU cover.
NOTE: Observe the high voltage warnings on the WIU cover.
____
TASK 20-41-02-402-048
7. Wire Integration Unit (WIU) Cover - Installation
________________________________________________
A. Standard Tools and Equipment
(1) Wrist Straps - (Commercially Availavle)
B. Procedure
S 492-049
WARNING: USE A WRIST STRAP WITH A MINIMUM GROUNDING LEAD RESISTANCE OF
_______ 250 KILOHMS AND A MAXIMUM OF 1.5 MEGOHMS. USE OF A LOW RESISTANCE WRIST STRAP CAN CAUSE INJURY TO PERSONS IF A HIGH VOLTAGE SOURCE IS TOUCHED.
CAUTION: MAKE SURE YOU KEEP CONTAMINATION OR UNWANTED MATERIAL AWAY FROM
_______ THE SENSITIVE DEVICE. CONTAMINATION OR UNWANTED MATERIAL NEAR THE SENSITIVE DEVICE CAN CAUSE A MALFUNCTION IN THE SENSITIVE DEVICE.
(1) Do these steps to do a test of the wrist strap resistance:
(a) Use an ohmmeter to make sure the wrist strap assembly has a minimum resistance of 250 kilohms and a maximum of 1.5 megohms.
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747-400 MAINTENANCE MANUAL
(b)
Put the wrist strap on your wrist.
(c)
Use an ohmmeter to make sure the resistance is less than 10 megohm.
S 422-067
(2) Connect the wrist strap into the ELECTROSTATIC GROUND JACK of the card file.
S 942-065
CAUTION: THE GROUNDING LEAD ON THE WRIST STRAP MUST TOUCH THE
_______ SKIN TO GIVE THE PROTECTION THAT IS NECESSARY. FAILURE TO USE THE WRIST STRAP CORRECTLY CAN CAUSE DAMAGE TO THE ESDS PRINTED CIRCUIT BOARDS.
(3)
Attach the wrist strap correctly on the person that will remove the printed circuit board.
S 412-050
(4)
Install the WIU cover.
(5)
Remove the wrist strap.
(6)
Install the protective cover.
S 092-051
S 412-052
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