Use A Single Point Ground; Connect The Power Wires Correctly; Apply Correct Input Voltage - Allen-Bradley 2711P Technical Data Manual

Use a Single Point Ground

Verify that the circuit powering the PanelView Plus terminal has only one point
where DC- is connected to earth/ground. This connection is usually internal to
the PanelView Plus terminal.
A circuit with DC- connected to earth/ground at more than one point has
portions of its DC- wiring electrically paralleled by an earth/ground path.
Current intended to return to the power source in the DC- wiring can return to
the power source through the parallel, earth/ground path.
For regulatory and reliability reasons, current must return to its power
IMPORTANT
source through the DC- wiring, not through earth/ground.
Most PanelView Plus terminals have DC- connected to earth/ground internally
in the product. Circuits powering these terminals must not have another DC-
point connected to earth/ground. Otherwise, the DC- current will flow through
the earth/ground wiring and earth/ground structure. Current flowing through
earth/ground can damage the terminal.
No other location powered by the same power source can have
IMPORTANT
DC- connected to earth/ground because the PanelView Plus terminal has
the internal ground connection.

Connect the Power Wires Correctly

ATTENTION: Do not perform a dielectric strength test on the nonisolated
DC powered terminals. High voltage will damage the product.
Make sure you connect the DC+ and DC- wires to the correct positions on the
power terminal block. The product is protected against the reversal of the DC+
and DC- connections. However, some miswiring combinations of the power
terminals and earth/ground or the communication wiring can damage the
PanelView Plus terminal or connected equipment.

Apply Correct Input Voltage

ATTENTION: Apply the correct voltage type to the DC power
terminal block.
Do not connect an AC power source to the DC power terminal block. This will
damage the PanelView Plus terminal.
Rockwell Automation Publication 2711P-TD001D-EN-P - February 2011
Wiring and Grounding Guidelines for PanelView Plus Terminals 25