Siemens 7SG11 Manual page 54

Observation
Cannot communicate with the relay.
Relays will not communicate in a ring
network.
Status inputs do not work.
Relay instrument displays show small
currents or voltages even though the
system is dead.
If the above checklist does not help in correcting the problem please contact Siemens Protection
Devices Limited
©2013 Siemens Protection Devices Limited
Action
Check that all of the communications settings match those used
by Reydisp Evolution. E.g. Protocol set to IEC 60870-5-103
Check that the Tx and Rx fibre-optic cables are connected
correctly.
( Tx –> Rx and Rx –> Tx ).
Check that all cables, modems and fibre-optic cables work
correctly.
Set the line idle setting to Light On. Examine the Tx port on the
back of the relay, with the fibre removed, and check that it is
glowing red. If it is not then the communications board on the case
may not be aligned correctly with the processor card socket.
Contact a Siemens Protective Devices Ltd representative.
(WARNING : DO NOT LOOK AT THE FIBRE-OPTIC
TRANSMITTER FOR A PROLONGED TIME).
Check that the Data Echo setting on all relays is set to ON.
Check that all relays are powered up.
Check that all relays have unique addresses.
Check that the correct DC voltage is applied and that the polarity
is correct.
Check that the status input settings such as the Pick-up and Drop-
off timers and the status inversion function are correctly set.
This is normal. The relay is displaying calculation noise. This will
not affect any accuracy claims for the relay.
7SG11 Argus User Manual
P20006 Page 36 of 37