Replacing Components With Compact Scales; Important Notes - KERN FTB Service Manual

5

Replacing components with compact scales

5.1

Important notes

This section describes how to change individual components of the compact scales. When doing this, please refer to the
exploded view drawings and spare parts lists in Chapters 2 and 3. Important: After replacing components, a functional check
of the scale must always be carried out.
5.1.1 Safety and environment
The following instructions must be observed for all repairs:
5.1.2 Tools and working aids
– Screwdrivers: Torx T10, T20, T25, and T30; Phillips 5 mm; flat type size 4
– Torque wrench up to 10 Nm
– Wrench heads Torx T25, T30, and hex 17 mm
– Open-end wrench, size 20
– Feeler gauge
– Carpet knife ("cutter")
– Grounded wriststrap (as protection against electrostatic discharges)
– Weights of class M1 or F1
5.1.3 Work instructions
Take great care when inserting and tightening screws into holes tapped directly into the aluminum casting: After inserting the
screw, always turn it first about 1 turn counterclockwise until it engages in the existing thread, and only then screw it tight! Do
not tighten the screw too much, since this may damage the thread in the aluminum casting!
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– Disconnect the scale from the power supply before starting repair work!
– The scale contains electronic components which can be damaged by electro-
static discharges. You must therefore always wear a grounded wriststrap
when performing repair work! Grounded wriststraps can be purchased from
specialist electronics dealers.
– Defective components must be disposed of according to the instructions in
Chapter 1!
• Servicing work in explosion hazard zones is strictly prohibited. Ignition
power could inadvertently be generated, causing an explosion. Servicing work
should therefore only be undertaken in secure areas. The location in which
the scale is installed must be declared by the system operator to be safe for the
duration of the repair work. If no such declaration is available, the scale must be
switched off and disconnected from the power supply and moved to a safe area.
• The scales can also be disconnected and reconnected to the power supply in
potentially explosive environments provided that the power supply has first been
switched off.
FTx/ITx-SH-e-0720