SNAP Isolated Analog Input
Modules
PA G E
1
DATA SHEET
Form 1182-081111
SNAP Isolated Analog Input Modules
Features
Channel-to-channel isolation
Rugged packaging and convenient pluggable wiring.
Accepts up to 14 AWG wire.
Factory calibrated; no user adjustment necessary
Out-of-range indication
Operating temperature 0 °C to 70 °C
Description
SNAP I/O isolated analog input modules provide two channels
isolated from each other, thereby eliminating problems caused by
ground loop currents. These isolated analog modules are part of
Opto 22’s SNAP PAC System and mount on SNAP PAC racks with an
I/O processor (brain or on-the-rack controller).
Since many SNAP analog input modules are software-configurable
and handle a wide variety of signal levels, a small number of
modules can support a full range of analog input requirements.
Modules provide high resolution for precise signal levels, as well as
dual-channel packaging. All SNAP analog modules are factory
calibrated. Part numbers ending in -FM are Factory Mutual
approved. Dimensional drawings are on pages 11–14.
SNAP analog input modules have an on-board microprocessor to
provide module-level intelligence, making them an ideal choice for
Original Equipment Manufacturers (OEMs). For more information
about the standalone operation of SNAP analog modules, see the
SNAP I/O Module Integration Guide (Opto 22 form #876).
Notes for legacy hardware: These modules can also be used
with SNAP Simple, SNAP Ethernet, and SNAP Ultimate brains, as
well as SNAP mistic brains such as the serial B3000. These modules
can be installed on M-series or B-series mounting racks.
Isolation
All SNAP analog input modules are transformer isolated as well as
optically isolated from all other modules and from the SNAP brain
or on-the-rack controller. In addition, the modules described in this
data sheet feature two channels isolated from each other.
Transformer isolation prevents ground loop currents from flowing
between field devices and causing noise that produces erroneous
readings. Ground loop currents are caused when two grounded
field devices share a connection, and the ground potential at each
device is different. Optical isolation provides 4,000 volts of transient
(4,000 V for 1 ms) protection for sensitive control electronics from
industrial field signals.
Channel-to-channel isolation gives you complete freedom from
ground-loop problems even on grounded devices connected to
channels on the same module.
Part Numbers
Part Description See
pg
SNAP-AIARMS-i
SNAP-AIARMS-i-FM*
Isolated two-channel 0 to 10
amp RMS AC/DC input 2
SNAP-AIVRMS-i
SNAP-AIVRMS-i-FM*
Isolated two-channel 0 to 250 V
RMS AC/DC input 3
SNAP-AIMA-i Isolated two-channel analog
current input -20 mA to +20 mA 4
SNAP-AIMA-iSRC
SNAP-AIMA-iSRC-FM*
Isolated two-channel analog
current input -20 mA to +20
mA, with loop sourcing
5
SNAP-AIMA2-i Isolated two-channel analog
current input -1 mA to +1 mA 6
SNAP-AITM-i
Isolated two-channel analog
type E, J, or K thermocouple or
-150 mV to +150 mV input
or -75 mV to +75 mV input
7
SNAP-AITM2-i
Isolated two-channel analog
type B, C, D, G, N, T, R, or S
thermocouple or -50 mV to
+50 mVDC input or -25 mV to
+25 mVDC input
8
SNAP-AIV-i
Isolated two-channel analog
voltage input-10 VDC to +10
VDC or -5 VDC to +5 VDC
9
SNAP-AIV2-i
Isolated two-channel analog
voltage input -100 VDC to +100
VDC or -50 VDC to +50 VDC
10
* Factory Mutual approved
SNAP Isolated Analog Input Modules
SNAP Isolated Analog Input Modules
SNAP Isolated Analog Input Modules
PA G E
10
DATA SHEET
Form 1182-081111
Description
The SNAP-AIV2-i module can be configured for either -100 VDC to
+100 VDC or -50 VDC to +50 VDC operation on each channel. The
SNAP-AIV2-i provides two channels that are isolated from each other.
Since these channels do not share any common connections, grounded
sensors and field devices may be used with them.
Specifications
Part Number Description
SNAP-AIV2-i Isolated two-channel analog voltage input
-100 VDC to +100 VDC or -50 VDC to +50 VDC
Input Range From -100 volts to +100 volts
From -50 volts to +50 volts
Resolution
4.0 mV when configured -100 volts to
+100 volts
2.0 mV when configured -50 volts to
+50 volts
Input Filtering -3 dB @ 64 Hz
Input Response Time
(% of span/ DV / Dt) 63.2% / 6.7 V / 10 mS
DC Common Mode
Rejection >-120 dB
AC Common Mode
Rejection >-120 dB @ 60 Hz
Maximum Survivable
Input 220 VAC or 300 VDC
Maximum Operating
Common Mode Voltage 250 V
Accuracy 0.05%, 50 mV @ 100 VDC
25 mV @ 50 VDC
Gain Temperature
Coefficient 30 PPM/ °C
Offset Temperature
Coefficient 15 PPM/ °C
Isolation: Optical 4000 V
Isolation: Transformer 1500 V
Isolation: Channel to
Channel
250 V continuous
(1500 V transient)
Power Requirements 5 VDC (±0.15) @ 200 mA
Input Resistance 1 megohms (each channel)
Ambient Temperature:
Operating
Storage
0 °C to 70 °C
-25 °C to 85 °C
Isolated Voltage Input Module
-100 VDC to +100 VDC or
-50 VDC to +50 VDC
IMPORTANT: The mounting rack connector has 24 pins; the module
connector has 20 pins. The extra pins on the mounting rack connector
prevent misalignment of the module during installation.
SNAP Isolated Analog Input Modules
SNAP Isolated Analog Input Modules DATA SHEET
Form 1182-081111
PA G E
11
Dimensional Drawing
All Modules Except SNAP-AITM-i and SNAP-AITM2-i
SNAP Isolated Analog Input Modules
SNAP Isolated Analog Input Modules
PA G E
14
DATA SHEET
Form 1182-081111
Dimensional Drawing
