Rockwell Automation 440R-D22R2, User Manual

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Rockwell Automation Publication 440R-UM013F-EN-P - July 2021 21
Chapter 3 Power, Ground, and Wire
need to be connected to the safety relay pulse-testing outputs. These devices
must have a common power supply reference (24V Com).
Figure 10 shows a typical example of the connections for devices, like light
curtains or laser scanners, with non-cascadable OSSD outputs.
Figure 10 - Example Connections to Devices with Non-cascadable OSSD Outputs
Figure 11 on page 22 shows an example of a wiring configuration that includes
non-cascadable and cascadable devices. The non-cascadable devices (Devices 1
and 2) must always start the cascade. Many cascadable devices (Devices 3…6 or
more) can be included in the input circuit. All devices must have the same
voltage supply reference (for instance, 24V Com) as the safety relay.
Examples of non-cascadable devices include GuardShield light curtains,
SafeZone laser scanners, and safety sensors. Examples of cascadable devices
include SensaGuard interlocks, and the TLS-ZR and 440G-LZ guard locking
interlocks.
Devices with electromechanical (EM) outputs must be placed after the non-
cascadable device. The EM safety relay devices can be placed anywhere in the
chain after the first OSSD device.
From the perspective of the GSR safety relay, only the OSSD device closest to
the relay (Device 3 in
Figure 11 on page 22 ) is of concern. The other devices with
OSSD outputs do not affect the performance of the safety relay. The EM safety
relay devices can suffer from masked faults, their safety rating is limited to
Category 3 per ISO13849-1.
• OSSD1 can be connected to either S12 or S22 and OSSD2 can be connected to either
S12 or S22.
• The safeguarding devices must have the same voltage supply reference (24V Com)
as the safety relay.
ATTENTION: You must consider the cumulative response time of all
cascaded devices, the relay, and output devices to verify that the safety
function is fulfilled within the required time that the risk assessment
determines.
S12
A2
A1
A2
S22 S32 S42
A1
A2
A1 A1 S12 S22
A2
+24V DC
24V Com
A1
A2
Device 1 Device 1
Device 2
Input 1 Input 1 Input 2
CI and SI
DI and DIS