Siemens S7-400 Benutzerhandbuch

4-39

S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07

The input values of the SM 421; DI 16 

 

 24 DC are affected by certain errors and

the parameter assignment of the module. The following table lists the effects on the
input values.

You will find more diagnostic messages of the module in the Appendix entitled
“Diagnostic Data of the Signal Modules”.

Table 4-15 How the Input Values Are Affected by Faults and by the Parameter Assignment of the 

SM 421; DI 16 

 

 24 VDC 

Module not
parameterized

Cannot be
disabled

Not relevant

0 signal (all channels)

No front connector

SV

Parameterized substitute value

KLV

Last read, valid value

Incorrect parameters
(module/channel)

Cannot be
disabled

Not relevant

0 signal (module/all incorrectly
parameterized channels)

STOP operating mode

Cannot be
disabled

–

Process value (not updated)

Internal voltage failure

Cannot be
di

bl d

SV

Parameterized substitute value

disabled

KLV

Last read, valid value

Hardware interrupt lost

Cannot be
disabled

Not relevant

Current process value

Wire break (for each

h

l)

Deactivated

–

0 signal

channel)

Activated

SV

Parameterized substitute value

KLV

Last read, valid value

Sensor supply missing
( l

  ti

t d i  

”N

Deactivated

–

0 signal

(also activated via ”No
Load Voltage L+”)

Activated

SV

Parameterized substitute value

Load Voltage L+ )

KLV

Last read, valid value

No load voltage L+ (for
each channel group)

Deactivated

–

0 signal, if the contact is connected via the
sensor supply; process value for the
external sensor supply

Activated

SV

Parameterized substitute value

KLV

Last read, valid value