schmersal PSC1-C-10 Series, Руководство по установке

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Installation manual
PSC1-C-10 Installation manual V2.6 Page 39 of 173
Version: 57E
4.2.1.2 DC digital sensors/inputs
The PSC1 modules provide wide-ranging diagnostic functions for the input sub-system. These are
designed as continuous, or optional (cross-circuit monitoring using pulse detection, cross comparison,
2-channel or multiple-channel sensor with/without time monitoring, start-up test).
Continuously active diagnostic functions:
Cross comparison:
The inputs on the PSC1 modules are in principle designed internally as dual channel. The status of the
input signals is continuously cross compared. Only with a high signal in both input sub-systems is the
high status of the input detected, if the signal level varies between the two channels, the input is set to
low status.
Dynamic test on the switching thresholds in the input sub-system:
The switching thresholds for the detection of the high level are tested cyclically with a high rate. If the
defined threshold is dropped below, a module alarm is triggered.
Dynamic test on the ability of the input sub-system to switch:
The ability of the input sub-system to switch to the low level is tested cyclically on all inputs except for
I04
— I07, with a high rate. If the defined threshold is dropped below, a module alarm is triggered.
Diagnostic functions that can be activated by configuring parameters:
Cross-circuit test:
The PSC1 modules have pulse signal outputs on which a unique signature is superimposed. On the
usage of the cross-circuit test, the switching elements for the digital sensors / input elements are
supplied with an auxiliary voltage via the pulse signal outputs on the PSC1 module. In this way the
signature is superimposed on the sensors' / input elements' high signal level and checked by the PSC1
module. Short-circuits and cross-circuits to the high signal can be detected by means of the signature
check. With alternating usage of the pulse signals for multiple contacts, parallel signal wires or with
neighbouring terminal assignment, cross-circuits between the related input signals are detected.
Sensors / input elements with 2-pole or multiple pole contacts without time monitoring:
The sensors/input elements can be assigned to several contacts. These therefore correspond to at
least 2-channel elements. A high level on the sensor/input element requires the logical connection in
series of both contacts.
Example 1:
Input element with 2 normally closed contacts: High level if both contacts are closed
Example 2:
Input element with 1 normally closed contact and 1 normally open contact: High level if normally open
contact actuated and normally closed contact not actuated.