Maintenance
7-9
AutomationSystem S7-400 Hardwareand Installation
A5E00850741-01

7.5 Changing the Fuses in the Digital Modules

Modules with Fuses

The following modules have fuses which you can change yourself if they are
defective:
Digital output module SM 422; DO 16 x DC 20--125V/1,5A
(6ES7422-5EH10-0AB0)
Digital output module SM 422; DO 16 x AC 20-120 V/2A
(6ES7422-5EH00-0AB0)
Digital output module SM 422;DO 8 xAC 120/230 V/5A
(6ES7422-1FF00-0AA0)
Digital output module SM 422;DO 16 xAC 120/230 V/2A
(6ES7422-1FH00-0AA0)

Check the Plant

Correct the faults which led to the fuses blowing.

Changing the Fuses

Tochange the fuses in a digital module, you must remove the front connector from
the digital module and remove the module from the rack.
!
Warning
Improper handling of the digital modules can result in injury and damage.
Hazardous voltages of >25 VACor >60 VDC may be present below the covers on
the right-hand side of the module.
Before you open these covers, ensure that either the front connector for the
module is removed or the module is disconnected from the voltage supply.