COSMOS DRIVER SERIES 3000 - USE AND MAINTENANCE MANUAL
If you consider the error list (21÷32) in the previous paragraph, you can find the situations listed here below:
11.2.2.1 Errors from 21 to 25
They occur during the phase increase in SERCOS communication SERCOS. In fact, before the system becomes
operational, it must be synchronized with the control unit; the synchronization procedure consists of 4 standard phases
according to the interface specifications.
Error 21:
the device
was not addressed by the control unit. This condition is not necessarily a problem: if you are not
going to enable the axis controlled by the driver, you can avoid considering the device. The SERCOS ring will continue
working. Otherwise, it is necessary to check the address setting and the controller, as indicated in paragraph “
SERCOS
interface configuration”.
Error 22:
the device was correctly addressed but it can not change the phase. This may be due to the absence of the
address of another device searched by the control unit, which consequently interrupted the communication.
Error 23:
it may occur at the beginning of phase 2. The system did not initialize the non-cyclic communication (see
standard SERCOS). This may be due to the device and/or control unit failure.
Error 24 and 25 :
transition from phase 2 to phase 3 (24) or from phase 3 to phase 4 (25) was not possible. This is
due to wrong exchange of configuration parameters (time, structure of the cyclic message, unsuccessful procedural
commands). Check the control unit programme.
11.2.2.2 Errors from 28 to 30
These errors are strictly linked to phase 4, in which the communication is synchronized with the control unit and is fully
operational.
Error 28:
It indicates the control unit's attempt to carry out a phase change that is not allowed. In fact, for the interface
specifications, only the transitions to phase 0 are considered as valid.
Error 29 and 30:
they signal the loss of a part of SERCOS message structure twice in the device. Together with error
32, they identify where the problem occurs inside the ring.
11.2.2.3 Error 32
It can occur at any time during the communication. It indicates an interruption of the light signal transmitted by the
optical fiber, due to an excessive attenuation or total absence of the signal. Here are the possible causes:
1. The optical fiber features one or more zones where the bend radius is too narrow;
2. The connection is made by means of fixed or mobile joints which imply high signal losses;
3. The device in previous position inside the ring is not working.
11.2.2.4 Examples of errors
In order to better understand the previous errors, we will make some examples of typical situations that might occur. We
will consider a SERCOS ring with 4 devices:
Ver. 1.07
Pag. 98
Example of SERCOS ring
COSMOS 1
TX
RX
COSMOS 2
TX
RX
COSMOS 3
TX
RX
COSMOS 4
TX
RX
SERCOS
Control
unit
RX
TX
