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The RAM is checked during the initialization of the device. In addition, the firmware in the Flash
memory is checked by means of a checksum during initialization. When the control system
(PLC/central unit) is stopped during normal operation, the outputs of the device 07DC91-AD are
switched off. The inputs remain active. The outputs are also switched off in case of a malfunc-
tion of the CS31 bus.
1.5.1.7
Diagnosis and Displays
LEDs are used for diagnosis and display purposes. In addition, some diagnosis information can
be transmitted via the CS31 bus.
The replacement device does not provide a test button to measure functionality.
Table 34: Diagnosis information of the CS31 bus
Error description
Channel
Error code
(CODESYS)
Error code
(CS31 bus)
Description
Device error
0
43
1
Internal error
Channel error
0, 4, 8, 12 *)
46
4
Overload or short
circuit on a digital
output
*) The channel numbers are grouped as follows:
0 - for X5/3.0, X5/3.1, X5/3.2, X5/3.3
4 - for X5/3.4, X5/3.5, X5/3.6, X5/3.7
8 - for X6/4.0, X6/4.1, X6/4.2, X6/4.3
12 - for X6/4.4, X6/4.5, X6/4.6, X6/4.7
The error codes that are transferred by the replacement device via the CS31
bus bus are newly displayed in CODESYS. Each error code of the CS31 bus
(table column 3) produces the error code in CODESYS (table column 2). As a
result, it is possible to operate the replacement device with a new control
system (PLC/control unit), e.g. 07KT98-ARC-AD, as well as with an old control
system (PLC/central unit), e.g. 07KT98.
Table 35: Device LEDs
LED
Status
Color LED off
LED on
LED flashes
PWR
Voltage supply
Gree
n
No internal supply
voltage
Internal supply
voltage
-
CS31
bus
CS31 bus com-
munication
Gree
n
No CS31 bus com-
munication
CS31 bus bus
communication
Only diagnosis, no
data transfer. Trans-
mission is disturbed.
S-ERR
Error
Red
No error
Static error
(must be con-
firmed by the
control system)
No CS31 bus con-
nection or activity
I/O bus I/O bus commu-
nication
Gree
n
No I/O bus commu-
nication
I/O bus com-
munication
Error I/O bus com-
munication
AC31 Adapters
Replacement devices: I/O modules > Replacement device 07DC91-AD
2018/09/24
3ADR010122, 8, en_US
66