cFP-RLY-425
10
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initial configuration information to the cFP-RLY-425. After the
cFP-RLY-425 receives this initial information, the green
READY
indicator lights and the module is in normal operating mode.
Isolation and Safety Guidelines
Caution
Read the following information before
attempting to connect the cFP-RLY-425 to any circuits
that may contain hazardous voltages.
This section describes the isolation of the cFP-RLY-425 and its
compliance with international safety standards. The field wiring
connections are isolated from the backplane and the inter-module
communication bus. The isolation barriers in the module provide
250 V
rms
Measurement Category II continuous isolation, verified
by 2,300 V
rms
, 1 minute dielectric withstand test. The
cFP-RLY-425 provides
double insulation
(compliant with
IEC 61010-1) for working voltages of 250 V
rms
1
. Safety standards
(such as those published by UL and IEC) require the use of double
insulation between hazardous voltages and any human-accessible
parts or circuits.
Never
try to use any isolation product between human-accessible
parts (such as DIN rails or monitoring stations) and circuits that
can be at hazardous potentials under normal conditions, unless the
product is specifically designed for such an application, as is the
cFP-RLY-425.
Even though the cFP-RLY-425 is designed to handle applications
with hazardous potentials, follow these guidelines to ensure a safe
system:
•
You
must
connect the protective earth (PE) ground terminal on
the cFP-BP-
x
backplane to the system safety ground. The
backplane PE ground terminal has the following symbol
stamped beside it:
. Connect the backplane PE ground
terminal to the system safety ground using 14 AWG (1.6 mm)
wire with a ring lug. Use the 5/16 in. panhead screw shipped
with the backplane to secure the ring lug to the backplane PE
ground terminal.
1
Working voltage
is defined as the signal voltage plus the common-mode voltage.
Common-mode voltage
is the voltage of the module with respect to ground.
