Proface LT3300 - 5.7 All-in-One HMI" - Manual (Page 13)

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(3) Attach the Power connector (Plug) to the
Power Connector.
2. Power Supply Cautions
• Input and Output signal lines must be sepa-
rated from the power control cables for
operational circuits.
• To improve the noise resistance, be sure to
twist the ends of the power cord wires
before connecting them to the Power con-
nector (Plug).
• The LT unit’s power supply cord should
not be bundled with or kept close to main
circuit lines (high voltage, high current), or
input/output signal lines.
• To reduce noise, make the power cord as
short as possible.
• If the supplied voltage exceeds the LT
unit’s range, connect a voltage transformer.
• Between the line and the ground, be sure to
use a low noise power supply. If there is an
excess amount of noise, connect a noise
reducing transformer.
• The temperature rating of field installed
conductors: 75
°C only.
• Use voltage and noise reducing trans-
formers with capacities exceeding
Power Consumption value.
• Must be used with a Class 2 Power Supply.
(24VDC)
• Connect a surge absorber to handle power
surges.
• Be sure to ground the surge absorber
(E1) separately from the LT unit (E2).
Select a surge absorber that has a max-
imum circuit voltage greater than that of
the peak voltage of the power supply.
3. Grounding Cautions
• Be sure to create an exclusive ground for
the Power Cord’s FG terminal. Use a
grounding resistance of 100
Ω, a wire of
2mm
2
or thicker, or your country’s applica-
ble standard.
• The SG (signal ground) and FG (frame
ground) terminals are connected internally
in the LT unit.
When connecting the SG line to another
device, be sure that the design of the sys-
tem/connection does not produce a short-
ing loop.
• The grounding wire should have a cross
sectional area greater than 2mm
2
. Create
the connection point as close to the LT unit
as possible, and make the wire as short, as
possible. When using a long grounding
wire, replace the thin wire with a thicker
wire, and place it in a duct.
Power Connector (Socket)
Power Connector (Plug)
FG
+
-
Lightening Surge Absorber
E1 E2
FG
LT
LT unit
Other
Equipment
Exclusive Grounding
(BEST)
LT unit
Other
Equipment
Common Grounding (OK)
LT unit
Other
Equipment
Common Grounding
(Not OK)