Siemens SIMATIC HMI 177 Mode D'emploi page 12

Operator controls and displays
Safety Functions of the STOP Button
The STOP button on the mobile panel brings about a stop of the system being monitored in accordance with EN 60204-
1:2006, Section 9.2.5.3. You have the option of implementing a Category 0, 1, or 2 stop function in accordance with EN
60204-1: 2006, Section 9.2.2. The stop function category must be selected on the basis of a risk assessment.
The stop function of the mobile panel can therefore be used as a reliable machine stop as well as for looping in the
emergency stop circuit of the system to be monitored.
WARNING
Category 0 or 1 Stop
If a Category 0 or 1 stop circuit is implemented, the stop function must be in effect regardless of the operating mode. A
Category 0 Stop must have precedence. Releasing the STOP button must not initiate any dangerous state (see also EN
60204-1:2006, section 9.2.5.3).
The stop function is not to be used as a replacement for safety equipment.
Enabling Switch
Introduction
The enabling buttons meet the requirements of Category 3 PL d in accordance with EN ISO 13849-1:2008/AC:2009 when
used in combination with an external monitoring device.
Category 3 PL d in accordance with EN ISO 13849-1:2008/AC:2009 can be achieved by implementing the enabling
apparatus with 2 circuits and suitable monitoring for shorting and crossing of these circuits.
Risk from improper use
Prohibited fixation of the enabling button in the "Enable" position by mechanical means is considered foreseeable misuse,
which can be prevented. We recommend the following measures for this, which result in bringing the machine to a standstill
in manual mode:
● Scan the enabling buttons.
The scan has to be carried out for the following processes:
– When the system being monitored is switched on
– When the operating mode changes from "Automatic" to "Manual mode"
In both cases, the enabling function may not be used.
● The enabling button must be released within a specified time frame and returned to the "Enable" position.
Select the time frame according to the activity on the system being monitored.
Specifications
Note
The fail-safe performance characteristics in the technical data apply to a proof-test interval of 20 years.
STOP button
Rated voltage
Minimum current
Max. current carrying capacity
Utilization category
B
10d
12
24 V DC
10 mA, per contact
500 mA, per contact
DC-13, in accordance with IEC 60947-5-1
100 000
Approval in accordance with EN ISO 13849-1:2008/AC:2009
A5E02519749-04, 12/2012