Diagnostics in User Program with S7-1500 STEP 7 (TIA Portal), S7-1500

4 Function Mechanisms

4.6 Function block DiagSignalFB [FB4]

4.6

Function block DiagSignalFB [FB4]

The function block monitors a binary signal and creates program and diagnostic messages.

Interfaces

Figure 4-14 Call in “DiagMainOB [OB123]”

Table 4-12

Type Parameter

Input Signal

UserMsg

Data type

Bool

UserMsgStruct

Description

The signal to be monitored.

Data for user diagnostic message

Call of instruction „Program_Alarm“

Abbildung 4-15 Call „Program_Alarm“

Function description

The “Program_Alarm” instruction monitors the binary input signal and generates an incoming or outgoing program message if there is change of signal.

The block calls the “DiagUsrMsgFB” function block and in the process transfers the

“UserMsg” input data for a user diagnostic message.

Note If required, you can read out and evaluate the message status of the program message with the “Get_AlarmState” instruction. In the process, you can e.g.

check whether a message was acknowledged in order to then continue the sequence in the program.

Diagnostics in User Program with S7-1500

Entry ID: 98210758, V1.0, 09/2014 25

4 Function Mechanisms

4.6 Function block DiagSignalFB [FB4]

The following figure shows the principle flow of the function block.

Figure 4-16

Start/Stop

Reading local time

Program_Alarm

(program message incoming / outgoing)

DiagUsrMsgFB

(FB Diagnostic message)

Start/Stop

Diagnostics in User Program with S7-1500

Entry ID: 98210758, V1.0, 09/2014 26