© National Instruments Corp. 9 cFP-RLY-421
Upgrading the FieldPoint Firmware
You may need to upgrade the FieldPoint firmware when you add
new I/O modules to the FieldPoint system. For information on
determining which firmware you need and how to upgrade the
firmware, go to ni.com/info and enter fpmatrix.
Isolation and Safety Guidelines
Caution Read the following information before
attempting to connect the cFP-RLY-421 to any circuits
that may contain hazardous voltages.
This section describes the isolation of the cFP-RLY-421 and its
compliance with international safety standards. The field wiring
connections are isolated from the backplane. The isolation is
provided by the module, which has optical and galvanic isolation
barriers designed and tested to protect against transient fault
voltages of up to 2,300 Vrms. The cFP-RLY-421 provides double
insulation (compliant with IEC61010-1) for working voltages of
250 Vrms1. 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-421.
Even though the cFP-RLY-421 is designed to handle applications
with hazardous potentials, follow these guidelines to ensure a safe
total system:
• The cFP-RLY-421 has a safety isolation barrier between the
I/Ochannels and the inter-module communication bus. There
is no isolation between channels unless otherwise noted. If any
of the channels on a module are wired at a hazardous potential,
make sure that all other devices or circuits connected to that
module are properly insulated from human contact.
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.