Overflow, Integrated protection mechanisms, 4function description – Pilz PSSu E S INC User Manual
Page 18: 1 module features, 2 integrated protection mechanisms
4.1
Module features
4
Function description
Pilz GmbH & Co. KG, Felix-Wankel-Straße 2, 73760 Ostfildern, Germany
Telephone: +49 711 3409-0, Telefax: +49 711 3409-133, E-Mail: [email protected]
4-2
4.1.1.2
Overflow
Overflow
4-
][Funktionsbeschreibung_Ein ST-INC BA Zhlerstand
In both operating modes the counter can accept values from
0000 0000
H
to FFFF FFFF
H
.
With an underflow the value drops below 0000 0000
H
and the coun-
ter continues from FFFF FFFF
H
.
With an overflow the value FFFF FFFF
H
is exceeded and the counter
continues from 0000 0000
H
.
The overflow or underflow is signalled to the head module as status in-
formation.
The status information overflow is reset:
if the value again falls below 0000 0000
H
(underflow).
if 5555 0000
H
is exceeded (the lower third of the value range).
The status information underflow is reset:
if FFFF FFFF
H
is exceeded again (overflow).
if AAAA FFFF
H
is exceeded (the upper third of the value range).
4.1.2
Integrated protection mechanisms
Integrated protection mechanisms
4-
][Schutzmechanismen E/A-Module
When the PSSu E F PS1(-T) is used to supply the system, the module
supply is buffered for 20 ms if the supply voltage is interrupted.
][Schutzmechanismen ST-Module
The module detects the following errors:
Start-up error
Configuration error
ST communication error
Bus termination error