Disassembly - Siemens SIPROTEC 7SJ61 Manual

Mounting and Commissioning
3.1 Mounting and Connections

3.1.2.2 Disassembly

Work on the Printed Circuit Boards
Note
Before carrying out the following steps, make sure that the device is not operative.
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 nameplates.
To perform work on the printed circuit boards, such as checking or moving switching elements or exchanging
modules, proceed as follows:
• Prepare working area: Provide a grounded mat for protecting components subject to damage from electro-
static discharges (ESD). The following equipment is required:
– screwdriver with a 5 to 6 mm wide tip,
– 1 Phillips screwdriver,
– 5 mm socket or nut driver.
• Unfasten the screw-posts of the D-subminiature connector on the back panel at location "A". This activity is
not necessary if the device is designed for surface mounting.
• If, besides the interface at location "A", there are further interfaces at location "B" and/or "C", also remove
the screws located diagonally to the interfaces. This is not necessary if the device is designed for surface
mounting.
• Remove the four or six caps on the front cover and loosen the screws that become accessible.
• Carefully take off the front cover.
Work on the Plug Connectors
Caution!
Mind electrostatic discharges
Non–observance can result in minor personal injury or material damage.
When working on plug connectors, electrostatic discharges must be avoided by previously touching a grounded
metal part.
Do not plug or withdraw interface connections under power!
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SIPROTEC, 7SJ61, Manual
C53000-G1140-C210-1, Release date 02.2008