These operating instructions describe how to install and use the
FP-AI-112 and cFP-AI-112 analog input modules (referred
to inclusively as the [c]FP-AI-112). For information about
configuring and accessing the [c]FP-AI-112 over a network, refer
to the user manual for the FieldPoint network module you are
using.
Features
The [c]FP-AI-112 is a FieldPoint analog input module with the
following features:
•16 analog voltage input channels
•Eight voltage input ranges: 0–1 V, 0–5 V, 0–10 V, ±60 mV, ±300 mV, ±1V, ±5V, and ±10 V
•16-bit resolution
•50 and 60 Hz filter settings
•250 V
verified by 2,300 V
•–40 to 70 °C operation
•Hot swappable
CAT II continuous channel-to-ground isolation,
rms
,1 minute dielectric withstand test
rms
Installing the FP-AI-112
The FP-AI-112 mounts on a FieldPoint terminal base (FP-TB-x),
which provides operating power to the module. Installing the
FP-AI-112 onto a powered terminal base does not disrupt the
operation of the FieldPoint bank.
To install the FP-AI-112, refer to Figure 1 and complete the
following steps:
1. Slide the terminal base key to either position X (used for any
module) or position 1 (used for the FP-AI-112).
2. Align the FP-AI-112 alignment slots with the guide rails on the
terminal base.
3. Press firmly to seat the FP-AI-112 on the terminal base. When
the FP-AI-112 is firmly seated, the latch on the terminal base
locks it into place.
4
5
3
6
1 I/O Module
2 Terminal Base
3 Alignment Slot
1
4Key
5 Latch
6 Guide Rails
Figure 1. Installing the FP-AI-112
2
Installing the cFP-AI-112
The cFP-AI-112 mounts on a Compact FieldPoint backplane
(cFP-BP-x), which provides operating power to the module.
Installing the cFP-AI-112 onto a powered backplane does not
disrupt the operation of the FieldPoint bank.
To install the cFP-AI-112, refer to Figure 2 and complete the
following steps:
1. Align the captive screws on the cFP-AI-112 with the holes on
the backplane. The alignment keys on the cFP-AI-112 prevent
backward insertion.
2. Press firmly to seat the cFP-AI-112 on the backplane.
FP-AI-112 and cFP-AI-1122ni.com
3. Using a number 2 Phillips screwdriver with a shank of at least
64 mm (2.5 in.) length, tighten the captive screws to 1.1 N ⋅ m
(10 lb ⋅ in.) of torque. The nylon coating on the screws prevents
them from loosening.
The FP-TB-x terminal base has connections for each of the
16 input channels and for an optional external power supply to
power field devices. The cFP-CB-x connector block provides the
same connections. Each channel has one input terminal (V
IN
) for
voltage input. All 16 inputs are referenced to the COM terminals,
which are internally connected to each other and to the C terminals.
The channels share eight V
You can use an external power supply to power field devices.
Connect the positive lead of the external power supply to both
V terminals and the negative lead to both C terminals. Ensure that
the current through both V terminals can never exceed 2 A.
Install 2 A maximum, fast-acting fuses between the external power
supply and the V terminals. The wiring diagrams in this document
show fuses where appropriate.
Table 1 lists the terminal assignments for the signals associated
with each channel. The terminal assignments are the same for the
FP-TB-x terminal bases and the cFP-CB-x connector blocks.
Table 1. Terminal Assignments
Terminal Numbers
Channel
011718
121718
231920
341920
452122
562122
672324
782324
892526
9102526
10112728
11122728
12132930
13142930
14153132
15163132
V
IN
V
SUP
COM
FP-AI-112 and cFP-AI-1124ni.com
Caution Cascading power between two modules defeats
isolation between those modules. Cascading power from
the network module defeats all isolation between
modules in the FieldPoint bank.
Measuring Voltage with the [c]FP-AI-112
Figure 3 shows how to connect a voltage source without an
external power supply to one channel of the [c]FP-AI-112.
VC
Voltage
Source
V
SUP
V
IN
+
–
COM
Input
Circuitry
>100 MΩ
Input
Impedance
[c]FP-AI-112
Figure 3. Voltage Source without External Power Supply
Figure 4 shows how to connect a voltage source with an external
power supply to one channel of the [c]FP-AI-112.
Powered
Voltage
Transducer
+
OUT
–
V
SUP
V
COM
External
Power Supply
(Optional)
IN
>100 MΩ
Input
Impedance
Input
Circuitry
+
–
2 A
Max
VC
[c]FP-AI-112
Figure 4. Voltage Source with External Power Supply
The input ranges for voltage signals are 0–1 V, 0–5 V, 0–10 V,
±60 mV, ±300 mV, ±1V, ±5 V, and ±10 V. To prevent inaccurate
readings, choose an input range such that the signal you are
measuring does not exceed either end of the range. Signals that
greatly exceed the configured range can adversely affect
measurements on other channels.
Measurements on a channel may be invalid for up to one update
period after you change the input range.
Overranging
The [c]FP-AI-112 has an overranging feature that measures a little
beyond the nominal values of each range. For example, the actual
measurement limit of the ±10 V range is ±10.4 V. The overranging
feature enables the [c]FP-AI-112 to compensate for field devices
with span errors of up to +4% of full scale. Also, the overranging
feature helps prevent errors caused by clipping.
Filter Settings
Three filter settings are available for each channel. The filters
on the [c]FP-AI-112 input channels are comb filters that provide
notches of rejection at multiples, or harmonics, of a fundamental
frequency. You can select a fundamental frequency of 50, 60,
or 500 Hz. At the 50 and 60 Hz settings, the [c]FP-AI-112 applies
95 dB of rejection at the fundamental frequency and at least 60 dB
of rejection at each of the harmonics. In many cases, most of the
noise components of input signals are related to the local AC power
line frequency, so a filter setting of either 50 or 60 Hz is best.
The 500 Hz filter setting provides faster update rates but much less
accurate measurements.
Update Rate
The update rate of the [c]FP-AI-112 is determined by the filter
settings and the number of input ranges in use. Higher filter
settings and fewer input ranges yield faster update rates. Use the
following formula to determine the approximate update period:
(number of channels with 50 Hz filter) × 0.061 s +
(number of input ranges with 50 Hz filter) × 0.12 s +
(number of channels with 60 Hz filter) × 0.051 s +
1
The update rate is the reciprocal of the update period.
FP-AI-112 and cFP-AI-1126ni.com
1
(number of input ranges with 60 Hz filter) × 0.10 s +
(number of channels with 500 Hz filter) × 0.007 s +
(number of input ranges with 500 Hz filter) × 0.012 s + 0.16 s
= Update Period
For the fastest performance, configure all unused channels for the
500 Hz filter setting and for an input range in use on one or more
other channels with the 500 Hz filter setting. For example, if
10 channels are configured for 0–10 V input and 500 Hz, four
channels are configured for 0–5 V and 60 Hz, and two channels
are unconnected, use the FieldPoint software to configure the
unconnected channels for 0–10 V input and 500 Hz filter setting.
Some combinations of two input ranges count as only one range for
calculating update rates. Those combinations are ±60 mV and
±300 mV; 0–1 V and 0 –5 V; and ±1 V and ±5V.
The update rate does not affect the rate at which the network
module reads the data. Set up your application so that the update
rate is faster than the rate at which the network module polls the
[c]FP-AI-112 for data.
Status Indicators
The [c]FP-AI-112 has two green status LEDs, POWER and
READY. After you insert the [c]FP-AI-112 into a terminal base or
backplane and apply power to the connected network module, the
green POWER indicator lights and the [c]FP-AI-112 informs the
network module of its presence. When the network module
recognizes the [c]FP-AI-112, it sends initial configuration
information to the [c]FP-AI-112. After the [c]FP-AI-112 receives
this initial information, the green READY indicator lights and the
module is in normal operating mode.
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 your
firmware, go to
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
2,300 V
provides double insulation (compliant with IEC 61010-1) for
working voltages of 250 V
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.
•Do not share the external supply voltages (the V and C
•For Compact FieldPoint, you must connect the protective earth
Installation Category II continuous isolation, verified by
rms
, 1 minute dielectric withstand test. The [c]FP-AI-112
rms
1
. Safety standards (such as those
rms
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.
terminals) with other devices (including other FieldPoint
devices), unless those devices are isolated from human contact.
(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.
FP-AI-112 and cFP-AI-1128ni.com
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.
•As with any hazardous voltage wiring, make sure that all
wiring and connections meet applicable electrical codes and
commonsense practices. Mount terminal bases and backplanes
in an area, position, or cabinet that prevents accidental or
unauthorized access to wiring that carries hazardous voltages.
•Do not use the [c]FP-AI-112 as the only isolating barrier
between human contact and working voltages higher than
250 V
•Operate the [c]FP-AI-112 only at or below Pollution Degree 2.
Pollution Degree 2 means that only nonconductive pollution
occurs in most cases. Occasionally, however, a temporary
conductivity caused by condensation must be expected.
•Do not operate FieldPoint products in an explosive atmosphere
or where there may be flammable gases or fumes. If you need
to operate FieldPoint products in such an environment, the
FieldPoint products must be in a suitably rated enclosure.
•Operate the [c]FP-AI-112 at or below Installation Category II.
Installation Category II is for measurements performed on
circuits directly connected to the low-voltage installation.
This category refers to local-level distribution, such as that
provided by a standard wall outlet.
rms
.
Specifications
The following specifications are typical for the –40 to 70 °C
temperature range and for 50 and 60 Hz filter settings unless
otherwise noted. Specifications are subject to change without
notice.
Input Characteristics
Number of channels .......................... 16
ADC resolution................................. 16 bits at 50 or 60 Hz;
10 bits at 500 Hz
(refer to table)
Type of ADC..................................... Delta-sigma
These specifications apply only to the cFP-AI-112.
NI recommends Compact FieldPoint if your application
is subject to shock and vibration.
Operating vibration, random
(IEC 60068-2-64).............................. 10 –500 Hz, 5 g
rms
Operating vibration, sinusoidal
(IEC 60068-2-6)................................ 10 –500 Hz, 5 g
Operating shock
(IEC 60068-2-27).............................. 50 g, 3 ms half sine,
18 shocks at 6 orientations;
30 g, 11 ms half sine,
18 shocks at 6 orientations
Safety
This product is designed to meet the requirements of the following
standards of safety for electrical equipment for measurement,
control, and laboratory use:
•IEC 61010-1, EN 61010-1
•UL 61010-1
•CAN/CSA-C22.2 No. 61010-1
Note For UL, hazardous locations, and other safety
certifications, refer to the product label, or visit
ni.com/certification, search by model number or
product line, and click the appropriate link in the
Certification column.
Electromagnetic Compatibility
Emissions.......................................... EN 55011 Class A at 10 m;
FCC Part 15A above 1 GHz
Immunity........................................... EN 61326:1997 + A2:2001,
Note Refer to the Declaration of Conformity (DoC) for
this product for any additional regulatory compliance
information. To obtain the DoC for this product, visit
ni.com/certification, search by model number or
product line, and click the appropriate link in the
Certification column.
Mechanical Dimensions
Figure 5 shows the mechanical dimensions of the FP-AI-112
installed on a terminal base. If you are using the cFP-AI-112,
refer to the Compact FieldPoint controller user manual for the
dimensions and cabling clearance requirements of the Compact
FieldPoint system.
109.5 mm
(4.31 in.)
107.19 mm
(4.22 in.)
91.44 mm
(3.60 in.)
Figure 5. FP-AI-112 Mechanical Dimensions
FP-AI-112 and cFP-AI-11214ni.com
Where to Go for Support
For more information about setting up the FieldPoint system, refer
to these National Instruments documents:
•FieldPoint terminal base and connector block operating
instructions
Go to
ni.com/support for the most current manuals, examples,
and troubleshooting information.
National Instruments corporate headquarters is located at 11500
North Mopac Expressway, Austin, Texas, 78759-3504. National
Instruments also has offices located around the world to help
address your support needs. For telephone support in the United
States, create your service request at
the calling instructions or dial 512 795 8248. For telephone
support outside the United States, contact your local branch office:
FieldPoint™, National Instruments™, NI™, and ni.com™ are trademarks of National Instruments Corporation.
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