Siemens Simatic S7-300, Hardware And Installation Manual, Page: 159 / 242

Maintenance
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
9-11
9.6 Digital output module AC 120/230 V: Replacing the fuses
Fuses for Digital Outputs
the digital outputs of the following digital output modules are short-circuit protected
by individual fusing of the channel groups:
•
Digit output module SM 322; DO 16
×
A 120 V
•
Digit output module SM 322; DO 8
×
A 120 230 V
System check
Eliminate the causes of fuse tripping.
Replacement fuses
If replacement is required, you can use the following fuses:
•
8 A, 250 V fuse
–
Wickmann 19 194-8 A
–
Schurter SP001.013
–
Littlefuse 217.008
•
Fuse holder
–
Wickmann 19 653
Warning
Improper handling of digital output modules can cause injuries and property
damage.
Beware of dangerous live voltage > 25 VAC or > 60 VDC underneath the cover at
the right hand side of the module.
Always unplug the front connector or disconnect the module's power supply before
you open these covers.
Warning
Improper handling of front connectors can cause injuries and property damage.
When you remove the front connector during operation, beware of dangerous live
voltage > 25 VAC or > 60 VDC across the pins.
If the front connector is wired to such voltages, hot swapping of modules must
always be carried out by skilled or instructed electrical staff, in order to avoid
unintentional contact to the module pins.
Position of the Fuses
Digital output modules are equipped with 1 fuse per channel group. The fuses are
located at the left side of the digital output module. The figure below shows you the
location of the fuses on digital output modules.