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FP-AI-112 and cFP-AI-112
8
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Isolation and Safety Guidelines
Caution
Read the following information before 
attempting to connect the [c]FP-AI-112 to any circuits 
that may contain hazardous voltages.
This section describes the isolation of the [c]FP-AI-112 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
 Installation Category II continuous isolation, verified by 
2,300 V
rms
, 1 minute dielectric withstand test. The [c]FP-AI-112 
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 
[c]FP-AI-112.
Even though the [c]FP-AI-112 is designed to handle applications 
with hazardous potentials, follow these guidelines to ensure a safe 
total system:
There is no isolation between channels on the [c]FP-AI-112. 
If a hazardous voltage is present on any channel, all channels 
are considered hazardous. Make sure that all other devices and 
circuits connected to the module are properly insulated from 
human contact.
Do not share the external supply voltages (the V and C 
terminals) with other devices (including other FieldPoint 
devices), unless those devices are isolated from human contact.
For Compact FieldPoint, 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 
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.