Siemens SIPROTEC 6MD665, Manual

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3 Installation and Commissioning
98
6MD665 Manual
C53000-G1876-C103-3
3.1.2.2 Disassembly
Disassembly of the
Device
Note
It is assumed for the following steps that the device is not operative.
Work on the Printed
Circuit Boards
Caution!
Caution when changing jumper settings that affect nominal values of the device
As a consequence, the ordering number (MLFB) and the ratings that are stated on the
nameplate do no longer match the actual device properties.
If such changes are necessary, the changes should be clearly and fully noted on the
device. Self adhesive stickers are available that can be used as replacement name-
plates.
To perform work on the printed circuit boards, such as checking or moving switching
elements or exchanging modules, proceed as follows:
• Prepare area of work. Provide a grounded mat for protecting components subject
to damage from electrostatic discharges (ESD). The following equipment is
needed:
– screwdriver with a 5 to 6 mm wide tip,
– 1 Philips screwdriver,
– 5 mm socket or nut driver.
• On the rear panel, remove the studs of the subminiature socket at slot "A".
• If the device has additional system interfaces on slots "B" to "E" in addition to the
service interface at slot "A", each of the diagonal screws must be removed.
• Remove the four or six caps on the front cover and loosen the screws that become
accessible.
• Carefully take off the front cover. With device versions with a detached operator
panel it is possible to remove the front cover of the device right after having
unscrewed all screws.