Pepperl+Fuchs VAS-2A1L-K31, Manual

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Subject to reasonable modifications due to technical advances. © Fuchs, Printed in Germany
Fuchs Group · Tel.: Germany (6 21) 7 76-0 · USA (3 30) 4 25 35 55 · Singapore 7 79 90 91 Internet http://www.pepperl-fuchs.com
AS-i Safety Monitor for 2 AS-i circuits
Function and startup of the Safety Monitor
8.2.2 Earth/Ground Fault Detector
An Earth/Ground Fault exists when the voltage
U
GND
(Nominal value of
U
GND
=0,5 U
AS-i
.) is outside of the following range:
10% U
AS-i
≤
U
GND
≤
90% U
AS-i
This error substantially limits the noise immunity of the AS-i communication.
Ground faults are indicated on the master´s display as well as in AS-i Control
Tools.
8.2.3 Noise Detector
The noise detector detects AC voltages on AS-i, that are not initiated by an AS-i
master or AS-i slaves. These interference voltages can cause telegram distur-
bances.
A frequent cause are insufficiently shielded frequency inverters or improperly
routed cables.
Noises is indicated on the master´s display as well as in AS-i Control Tools.
8.2.4 Over-voltage Detector
Over-voltages are present if the conductors of an AS-i network that normally are
routed electrically symmetrical with respect to machine ground, are strongly elec-
trically raised. A cause can for example be startup procedures of large consu-
mers.
However, over-voltages do generally not interfere with the AS-i communication,
but can under certain circumstances cause incorrect sensor signals.
Over-voltages are indicated on the master´s display as well as in the AS-i Control
Tools.
8.3 Configuration of the safety functions
The device can be configured in several ways:
1.
Using ASIMON 3 G2 software
The ASIMON 3 G2 software represents the most universal method of confi-
guring the Safety Monitor. Here the behavior of the Safety Monitor can be
determined by linking various monitoring modules. After being sent to the
Safety Monitor, this configuration is verified and can then be validated.
Information!
To recognize ground faults the monitor must be grounded with its machine ground con-
nection.
Information!
A ground fault in one of the two networks of a double master in a version 1 power sup-
ply for two AS-i networks causes a ground fault in the other network as well because of
the the existing galvanic connection.