Siemens simatic hmi op7, Equipment Manual

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15-5
Equipment Manual OP7, OP17
Release 04/99
15.3 Start-up Behavior
ESC
No
Yes
OP starts up
Self test
No configuration exists
or
keys
pressed?
+
+
After the power supply has been turned on, the OP performs a
self test. In the test, it checks the operability of the most impor-
tant device components and displays the test results.
If there is not a configuration on the OP, the OP switches auto-
matically to Download mode.
Download
mode
Initialization
Establish connection
to PLC
Start screen or
standby message
The OP then performs various internal initializations.
In this start-up phase, the OP attempts to establish a connection
to the PLC.
If communication is not possible – for example, because the ca-
ble to the PLC has not been inserted – the OP displays a system
message.
After start-up, the OP displays the configured start screen. If a
start screen has not been defined, the standby message is dis-
played.