Functions; Functions Of The Safety Circuit I21-I11 And; Functions Of The Reset Circuit X1 - Zander Aachen SCB Serie Betriebsanleitung

Safety Time Control Device

7. Functions

The safety time control device SCB is conceptualised for the safe isolation of safety circu-
its according to EN 60204-1 and can be used in safety applications up to, PL e, Cat. 4,
SIL 3 as well as on furnaces in continuous operation according to EN 50156-1 and EN
746-2. Figure1 shows the block diagram of the SCB.
Y1
Figure1: Block diagram SCB
7.1 Functions of the safety circuit I21-I11 and I22-I12
Depending on the wiring, the input circuits I21-I11 and I22-I12 are used for two-channel or
single-channel control and thus monitoring of connected sensors.

7.2 Functions of the reset circuit X1

The reset behaviour of the SCB is determined via terminal X1 in combination with the se-
lected configuration. Automatic and monitored manual reset are available.
7.3 Functions of the feedback circuit Y1
If contactors or expansion modules are controlled via the SCB, they can be monitored via
a feedback circuit to terminal Y1. This prevents a restart in the event of a contactor failing
in a dangerous state.
H. ZANDER GmbH & Co. KG • Am Gut Wolf 15 • 52070 Aachen • Deutschland • Tel +49 241 9105010
Fax +49 241 91050138 • info@zander-aachen.de • www.zander-aachen.de
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