Siemens SIPROTEC 7SS523 V3.2 Manual page 313

8.4.2 Replacing the Fine-Wire Fuse
Central unit
Press the new battery firmly into its snap-in holder (see Figure 8-6, page 296 or
Figure 8-7, page 296). Observe the correct battery polarity!
Close the front cover and fasten it again to the housing with the screws.
Put the screw covers back on.
Switch the auxiliary voltage on again.
WARNING!
The spent battery contains lithium. The applicable regulations for its disposal must be
strictly complied with!
Do not reverse the polarity! Do not reload! Do not throw into the fire! Risk of
explosion!
The power supply modules SV in the central unit and SAF or SVW in the bay units are
protected against short-circuit by fine-wire fuses.
The ratings of the required fuses can be found for the central unit in
Figure 8-8, page 298, and for the bay units in Figure 8-9, page 299 or
Figure A-11, page 347.
Disconnect all auxiliary power circuit connections of the device at the miniature
circuit breaker.
Warning!
Hazardous voltages can be present in the device even after the power supply voltage
has been removed, i.e. capacitors can still be charged.
Caution!
Electrostatic discharges can occur if printed conductors, connectors and connecting
pins are touched. To avoid such electrostatic discharges, touch a grounded piece of
metal first.
To replace the fine-wire fuse in the central unit:
Remove the covering caps on the front panel, and unscrew the screws.
Swing the front panel downwards.
The fine-wire fuse is located on the power supply module (SV). This module is
plugged in at the rightmost slot in the rack (Figure 2-2, page 16).
Open the latch that holds the module in place.
Pull the module out of the housing. Use the extraction handle (included in the
delivery) to loosen the module.
To avoid electrostatic discharge through components, the withdrawn modules
7SS52 V4 Manual
C53000-G1176-C182-1
Repair
297