Rockwell Automation Allen-Bradley MobileView 2711T-VMBRACKET, User Manual

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Rockwell Automation Publication 2711T-UM001E-EN-P - March 2019 17
Safety Precautions and Elements Chapter 2
Power Supply All MobileView 2711T terminals meet the Safety Class III requirements for
electrical shock in accordance with EN 61131-2. See
Appendix A for the DC
power supply requirements for a MobileView 2711T terminal, junction box, and
connection cable.
Specifications of power supply lines in the connection cable s are:
• Cross section: 26 AWG (0.126 mm
2
)
• Material: zinc-coated copper strand
• Line resistance: <136 Ω/km (<219 Ω/mi)
Enabling Switch On the MobileView 2711T terminal, the enabling switch consists of a 3-position
operating element with two independent circuits.
Enabling Switch Connection Example with a Control Relay
Figure 3 on page 18 shows suggested wiring for the enabling switch with an
Allen-Bradley® safety control relay. If this wiring example is followed, then the
safety function meets Category 4, Performance Level e (CAT. 4, PLe) in
accordance with ISO 13849-1 or SIL 3 in accordance with EN 61508.
SHOCK HAZARD: Supply the MobileView terminal and junction box exclusively
from power sources with SELV or PELV circuit protection according to EN 61131-
2.
Only connect voltages and circuits that are separated from dangerous voltages (for
example, by means of sufficient insulation) to connections, terminals or interfaces
up to a rated voltage of 50V DC.
WARNING: The 24V DC power supply to the control cabinet or operator panel
must have a fuse that is rated 3.15A (max) and complies with UL 248.
Failure to install a fuse can result in fire from component failure.
WARNING: Only the operator of the enabling device on the MobileView 2711T
terminal is allowed in the dangerous area or zone.
The enabling switch is only suitable as a safety device if the operator of the enabling
switch on the MobileView 2711T terminal recognizes the dangerous situation and
reacts in time to avoid the danger.
Consider reduced speed of movements as a precautionary measure, which can be
done through the risk assessment of machinery.