7SR242 Duobias Commissioning & Maintenance Guide 
©2010 Siemens Protection Devices Limited     Chapter 6 Page 54 of 57 
Section 5: Testing and Maintenance 
7SR24 relays are maintenance free, with no user serviceable parts. 
5.1 Periodic Tests 
During the life of the relay, it should be checked for operation during the normal maintenance period for the site 
on which the product is installed. It is recommended the following tests are carried out:- 
1.  Visual inspection of the metering display  
2. Operation of output contacts 
3.  Secondary injection of each element 
5.2 Maintenance 
Relay failure will be indicated by the ‘Protection Healthy’ LED being off or flashing. A message may also be 
displayed on the LCD. In the event of failure Siemens Protection Devices Ltd. (or the nearest Siemens office) 
should be contacted – see defect report sheet in section 5.3. 
The relay should be returned as a complete unit. No attempt should be made to dismantle the unit to isolate and 
return only the damaged sub-assembly. It may however be convenient to fit the withdrawable relay to the outer 
case from a spare relay, to avoid the disturbance of relay panel wiring, for return to Siemens Protection Devices 
Ltd. The withdrawable relay should never be transported without the protection of the outer case. 
5.3 Troubleshooting 
Table 5-1  Troubleshooting Guide 
Observation Action 
Relay does not power up. 
Check that the correct auxiliary DC voltage is applied and that the 
polarity is correct. 
Relay won’t accept the password.  The Password being entered is wrong. Enter correct password. 
If correct password has been forgotten, note down the Numeric 
Code which is displayed at the Change Password screen e.g. 
 
 
 
To retrieve the password, communicate this code to a Siemens 
Protection Devices Ltd. representative. 
Protection Healthy LED flashes 
General failure. Contact a Siemens Protection Devices Ltd. 
representative. 
LCD screen flashes continuously. 
The LCD has many possible error messages which when 
displayed will flash continuously. These indicate various processor 
card faults. 
General failure. Contact a Siemens Protection Devices Ltd. 
representative. 
Backlight is on but no text can be seen.  Adjust the contrast. 
Scrolling text messages are unreadable.  Adjust the contrast. 
Relay displays one instrument after 
another with no user intervention. 
This is normal operation, default instruments are enabled. 
Remove all instruments from the default list and only add those 
that are required. 
 (See Section 2: Settings and Instruments). 
Change password  
       = 1234567