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Reliability Solutions
Product Data Sheet
July 2017
AMS 9420 Wireless Vibration Transmitter
„„Accurately monitors vibration and temperature
in hard-to-reach locations
„„Provides complete vibration data including
overall levels, energy bands, high resolution
spectra, and waveforms
„„Enables three ways to collect spectra:
time-based, on-alert, and on-demand
„„Includes Emerson’s unique PeakVue™
technology for bearing and gear diagnostics
„„Certified intrinsically safe for use in
hazardous areas
„„Delivers data and device alerts securely and
reliably via IEC 62591 (WirelessHART®) networks
„„Easily integrates into any host via Modbus or OPC
with detailed diagnostics via AMS Suite software
Overview
The rugged AMS 9420 Wireless Vibration Transmitter is the
first device to provide full vibration data over a self-organizing
wireless network. It provides rich information about machinery
health for both operations and maintenance personnel. Overall
vibration, PeakVue, and temperature readings can be easily
integrated into any control system or plant historian while
diagnostic data can be displayed by AMS Suite: Intelligent
Device Manager or any EDDL compliant host. For advanced
diagnostics, high resolution data can be delivered to AMS Suite:
Machinery Health Manager for trending and analysis.
The AMS 9420 delivers complete vibration information, including
high resolution spectra and waveform, over a self-organizing
wireless network for use by operations and maintenance personnel.
Cost-Effective, Reliable Monitoring
The AMS 9420 extends vibration monitoring to an entire
array of new applications. While appropriate for most
vibration monitoring tasks, it is especially well suited for
hard-to-reach locations, such as cooling towers, pumping
stations, remote equipment, and hazardous areas.
In general, the AMS 9420 provides an excellent solution
for any application that might otherwise involve
extensive engineering, cabling, or installation costs.
Advanced electronics deliver a high level of accuracy,
while the IEC-approved WirelessHART standard delivers
exceptional reliability.
AMS 9420 Wireless Vibration Transmitter
July 2017
Overall Condition in the Control Room
The AMS 9420 delivers information about the overall health of
rotating assets directly to the control room via Modbus or OPC.
Overall vibration data is a good indicator of shaft problems
such as imbalance, misalignment, or mechanical looseness.
In contrast, the PeakVue reading provides a reliable measure
of impacting on the machine. As the PeakVue level increases,
it provides direct indication of a developing problem, such as
improper lubrication, bearing fault, or gear defect. Process
induced faults, such as pump cavitation, are detected by an
increase in both the overall vibration and PeakVue readings.
Asset Dashboard at your Fingertips
AMS Device Manager generates an asset dashboard based on
the output of the AMS 9420. This intuitive interface displays the
health of the sensor, the transmitter, and the production asset
being monitored – extending the benefits of PlantWeb® to WirelessHART devices.
AMS Device Manager uses EDDL technology to create an asset
dashboard with clear indication of device and asset status.
PeakVue Technology
™
Focus on Impacting for Better Results
Traditionally, vibration data has not been routed to the
control room because it required specialized training —
and frequently specialized tools — to extract any information
from the data. Emerson’s unique PeakVue technology cuts
through the complexity of machinery analysis to provide a
simple, reliable indication of equipment health via a single
trend. PeakVue filters out traditional vibration signals to
focus exclusively on impacting, a much better indicator
of overall asset health on pumps, fans, motors, or any
other type of gearbox or rolling element bearing machine.
PeakVue measurements are easy to interpret and are
based on a concept called The Rule of Tens. For properly
installed and well-lubricated machinery that is not
impacting, the PeakVue measurement is at or close to zero.
If a problem develops, the PeakVue measurement climbs to
10g. A measurement of 20g indicates a serious problem in
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the bearing, even though overall vibration levels might not
indicate the same. When the measurement exceeds 50g,
failure is imminent.
State
Bearing Life
Remaining
Vibration
(in/sec)
PeakVue
(g’s)
New
Full
0.15
0
1
<20%
0.15
10
2
<10%
0.15
20
3
<5%
0.16
30
4
<1%
0.18
40
Failure
0%
>0.45
>50+
Typical values for a Horizontal Pump, direct coupled, with machine speed of 600-60000 RPM.
PeakVue data provides earlier indication of developing faults in
rolling element bearings and gearboxes.
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AMS 9420 Wireless Vibration Transmitter
Diagnostic Data to the Maintenance Office
AMS Machinery Manager automatically communicates detailed
diagnostic data to the maintenance office, including overall
values, energy bands, high resolution spectra, and waveforms.
Once stored in the AMS Machinery Manager database, these
measurements deliver the same diagnostic value as comparable
readings collected using Emerson’s industry- leading AMS 2140
Machinery Health Analyzer.
AMS Machinery Manager provides advanced analytical tools
to trend vibration levels, generate alerts, and diagnose
developing faults.
Information Available When You Need It
There are now three ways to collect high-resolution spectra
or waveforms:
1) Time-based: Collect readings automatically on a scheduled
basis, i.e. once every two weeks.
2) On-alert: Collect readings automatically whenever an alert
is registered based on either the overall vibration or the
PeakVue impacting.1
3) On-demand: Manually initiate a reading at any point when
current diagnostic data is required.
This allows you to quickly and easily access current health
information about your rotating assets without leaving
your desk.1
July 2017
Flexible Configuration Options
The Power to Get Things Done
There are two power options for the AMS 9420. For a truly
wireless experience, utilize the SmartPower™ Module. Based on
the low power output defined by the WirelessHART standard,
the AMS 9420 can achieve an operating life of up to 4 years
when using the Power Save option. An operating life of two to
three years can be achieved when using the default settings
(update rate set to 60 minutes).
For faster update rates, the external DC-powered terminal
block is recommended. This option provides virtually
unlimited operation, even at the minimum update rate
of once per minute.
Local Indication and Verification
The optional LCD display provides a local read-out of
sensor values and transmitter diagnostics to streamline
commissioning and troubleshooting at the device. Local
indication of vibration measurements and diagnostics
also provides accurate, real-time verification of operating
conditions. The LCD display can be rotated to facilitate easy
viewing, regardless of the orientation of the transmitter.
Plan and Manage Wireless Networks
The AMS Wireless SNAP-ON™ application is a revolutionary
tool that enables you to both plan and manage your wireless
network. Starting with a scale drawing of the plant, utilize
simple click-and-drag functionality to position the
gateways and wireless devices. Then the AMS Wireless
SNAP-ON application will compare the plan to industry
best practices. Recommendations will help you quickly
develop a reliable wireless network.
After the devices are installed, the AMS Wireless SNAP-ON
application will help you manage the network, providing
a graphical overview of the communication paths and
network health.
AMS Machinery Manager provides advanced analytical tools
to trend vibration levels, generate alerts, and diagnose
developing faults.
1
Requires AMS Machinery Manager version 5.61 or higher.
www.emerson.com/ams
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AMS 9420 Wireless Vibration Transmitter
Wireless Architecture Overview
Ultimate Simplicity
Built on the IEC 62591 (WirelessHART) industrial standard,
Emerson’s wireless network is completely self-organizing. There
is no need to configure communication paths because the
Smart Wireless Gateway manages this automatically –
including adapting to changing environments. Once the
network is established, new devices can be added at any time.
Conversely, even if a device is de-commissioned,
data reporting from other devices continues uninterrupted
over other established paths.
Easy Installation
The AMS 9420, like all Emerson’s Smart Wireless transmitters,
is simple to install. As soon as power is applied to the device,
it will automatically establish communication with neighboring
wireless devices, establish a path to the Gateway, and begin
reporting. Each transmitter also has the ability to function as
a repeater, relaying data from other devices to extend the
network across virtually any size facility or industrial campus.
Network Stability
The Smart Wireless Gateway connects the wireless network
with the host system and data applications like AMS Suite.
The Gateway manages all aspects of the network: executing
scheduled readings and accommodating requests for on-
demand acquisitions. The Gateway configures the network
to minimize power consumption and ensure network stability,
while maintaining data reliability well above 99%.
July 2017
Best-in-Class Security
Emerson’s multi-layered approach to wireless network
security builds on the IEC 62591 standard to ensure that
your data stays protected – no matter what. Authentication
and verification make certain that only authorized devices
can join the network, while 128-bit encryption shields your
information. Channel hopping maintains operation, even in
challenging environments.
Emerson’s Complete Smart Wireless Solution
Emerson has a complete portfolio of Smart Wireless transmitters for many applications, including temperature,
pressure, flow, and level. In addition, the Smart Wireless THUM™
Adapter can enable any HART device to wirelessly transmit measurement and diagnostic information. Emerson wireless
devices can be accessed and maintained remotely using the
same tools and software as wired devices, leveraging existing
practices, training, and maintenance procedures.
AMS Machinery Manager
DeltaV / Ovation
AMS Machinery Manager
Legacy System
At the heart of Emerson’s Smart Wireless solution is the selforganizing network, featuring tight security, infinite configurability,
and data reliability that rivals wired systems.
Seamless Integration to Host Systems
Easily configure and broadcast measurements to Emerson’s
DeltaV™ and Ovation™ digital automation systems; use Ethernet
IP™ to connect to Allen-Bradley® controllers; or apply Modbus
or OPC to report data back to most other automation systems
and/or data historians.
The AMS Wireless SNAP-ON application graphically displays your
wireless network.
www.emerson.com/ams
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AMS 9420 Wireless Vibration Transmitter
July 2017
Analyze Data in AMS Machinery Manager
High Resolution Spectrum
Vibration data from the AMS 9420 can be stored and analyzed
in AMS Machinery Manager. The Data Import module provides
easy data mapping using simple drag-and-drop commands.
AMS Machinery Manager combines predictive techniques with
comprehensive analysis tools for an accurate assessment of the
machinery health in your facility.
The first compression technique is FFT analysis, which
transforms the vibration waveform into a frequency
spectrum (shown below). This spectrum not only reduces
the file size by over 60%, it also presents the frequency
information in a more readable format. The smaller data
set accelerates responsiveness of the system while reducing
power consumption.
Detailed Reliability Data
Overall vibration indicates when a machine is running rough,
while the level of impacting detected by PeakVue signal
processing provides the operator with an indication about
the presence and severity of a serious defect such as underlubrication, bearing faults, gear defects, and pump cavitation.
Furthermore, once a machine has been flagged, detailed data
can be analyzed by a vibration specialist to verify the exact
nature of the fault. With the advanced diagnostics in the
AMS 9420, you have easy access to all of this
critical information.
High Resolution Waveform
The vibration waveform (shown below) is the basis for all
other vibration measurements performed by the AMS 9420.
Each waveform is a complex data set of thousands of samples,
collected over several seconds of machine operation.
While the acceleration waveform can be helpful in some applications, the PeakVue waveform is indispensable for
diagnosing developing bearing and gear defects. Because of
their large size, however, waveforms tend to be collected less
frequently. Emerson’s Smart Wireless solution employs several
data compression techniques to extract the information while
facilitating easier transmission over the network.
The elevated peaks in this high resolution spectrum provide a clear
indication of mechanical looseness on the machine.
Thumbnail Spectrum
The thumbnail spectrum is derived from the same
waveform data. It contains the same frequency and amplitude
information as the high resolution spectrum, but the data set
has been compressed by an additional 98%. Now it is small
enough to transfer over the network in less than a second.
The elevated peaks are still clearly visible in the thumbnail spectrum
and indicate the presence of mechanical looseness.
The acceleration waveform contains raw vibration data that allows
you to diagnose the health of the asset.
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AMS 9420 Wireless Vibration Transmitter
July 2017
Energy Bands
As a final data compression technique, the AMS 9420
divides the spectrum into three predetermined energy bands
(as shown below). It then calculates the vibration energy within
each energy band and passes these values to AMS Machinery
Manager for trending and alerts.
Band
Fault Types
Range
1
Rotor Vibration: Imbalance,
misalignment (also defects on
belt drives)
2–65 Hz
2
Rotor Harmonics: Looseness,
electrical faults, blade and
vane pass
65–300 Hz
3
High Frequency: Bearing and gear
defects, lubrication and cavitation
300–1000 Hz
Energy bands with frequency ranges. Optimized for a 4-pole motor
running between 1500 and 1800 RPM. Note: bands are fixed.
The trend of overall vibration suggests that machine health is
deteriorating but without any indication as to the root cause. The
trend of the high frequency energy band provides further insight,
which can be confirmed by examining the thumbnail spectra.
By trending the values in AMS Machinery Manager and comparing them to appropriate alert levels, it is possible to
set up a system of intelligent alerts that not only inform you
when the machine condition is deteriorating, but also provide
information about the underlying cause of the problem.
The figure illustrates how vibration data can be used to
detect and diagnose a developing fault. Based on the increase in
overall vibration (black line), an alert would flag the machine as
having a potential fault – but with no indication at all about the
nature or severity of the fault.
The trend of the three energy bands shows that the readings
for rotor vibration (green) and rotor harmonics (blue) are stable,
while the readings for high frequency vibration (red) have
increased sharply. This would trigger a special alert for
the rotating equipment specialist in AMS Machinery Manager.
By dividing the spectrum into energy bands, we can isolate
frequencies associated with different categories of faults.
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Examination of the thumbnail spectra (shown above the trend)
confirms that the fault is high frequency in nature. On-demand
acquisition of the PeakVue spectrum and waveform then provides conclusive insight into the specific nature of the
fault as well as its severity. Using the advanced diagnostics
in the AMS 9420 and AMS Machinery Manager, maintenance
personnel can often address and resolve an issue without it
ever registering as an alert in the control room.
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AMS 9420 Wireless Vibration Transmitter
July 2017
Functional Specifications
Inputs
Accelerometer 1
DC Bias Range: 2 - 3 Vdc
DC Input Range: 0 - 5 Vdc
AC Input Range: +/- 80 g’s peak (784 m/s2 peak)
Accelerometer 2
DC Bias Range: 2 - 3 Vdc
DC Input Range: 0 - 5 Vdc
AC Input Range: +/- 80 g’s peak (784 m/s2 peak)
Temperature
DC Input Range: -30° to + 121°C (-22°F to 250°F )
Standard Outputs
Machinery Health Values
Velocity overall (1 or 2 sensors)
PeakVue overall (1 or 2 sensors)
Temperature (1 sensor only)
Transmitter Health Values
Ambient temperature
Supply voltage
Sensor bias voltage (1 or 2 sensors)
Multiple internal alerts indicate the status of device health
Advanced Diagnostic Outputs (optional , requires link through an Emerson Smart Wireless gateway device)
Energy bands
Rotor vibration (2 - 65 Hz)
Rotor harmonics (65 - 300 Hz)
High Frequency (300 - 1,000 Hz)
Thumbnail Spectrum
Fmax: 150, 300, 600, or 1,000 Hz
High Resolution Vibration Spectrum
Fmax: 1,000 Hz
Resolution: 4002, 800 or 1,600 lines
Snapshot or Averaged (4 readings)
High Resolution Vibration Waveform
All measurements based on high resolution waveform with 4,096 points
High Resolution PeakVue Spectrum
Bandwidth: 1,000 - 20,000 Hz
Fmax: 1,000 Hz
Resolution: 1,600 lines
Snapshot of impacting on machine
High Resolution PeakVue Waveform
Sampled at 51,200 Hz;
High resolution with 4,096 points
Display
Units
English, metric or SI
Local Display
The optional five-digit integral LCD display provides readout of
HART parameters in engineering units (°F, °C, in/sec, mm/sec, g’s and m/s2).
Display updates for each transmission
Maximum update rate - once per minute
Update Rate
Standard: 1 min to 60 min (User selectable)
Power Save: up to 24 hours (User selectable)
Operating Conditions
Relative Humidity
0 - 95%
Temperature
Storage Temperature: -40°C to 85°C (-40°F to 185°F)
Operating Temperature without LCD meter: -40°C to 85°C (-40°F to 185°F)
Operating Temperature with LCD display: -20°C to 80°C (-4°F to 176°F)
(2) Device software version 5.1 or higher required for 400 line spectrum.
www.emerson.com/ams
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AMS 9420 Wireless Vibration Transmitter
July 2017
Physical Specifications
Power Options
SmartPower™ Module
Intrinsically safe
Replaceable
Lithium-Thionyl Chloride
External DC-power
Input Voltage: 10 - 28 VDC (peak current draw of 40 mA)
Provides unlimited operating life — recommended for applications requiring
faster update rates
Operating Life3
Values apply to Device Software version 5.020 and higher
Configuration
1
2
3
Overall Values (min)
30
60
2404
Energy Bands (hr)
8
8
8
Spectrum (hr)
24
24
24
30 (or on alert)
30 (or on alert)
30 (or on alert)
1 to 2
1.5 to 3
2 to 4
High Resolution Waveform & Spectrum (days)
Operating life (years)
Materials of Construction
Enclosure
Housing — Low-copper aluminum (standard)
Paint — Polyurethane
Cover O-ring — Buna-N
Terminal Block and Battery Pack
PBT
Antenna
PBT/PC integrated omni-directional antenna (standard)
Optional extended range antenna available in some markets.
Mounting
Vibration sensor must be mounted directly on asset being monitored
Transmitter may be mounted up to 100’ (30.5 m) away from sensor
Weight
2 kg (4.6 lbs.) without LCD
2.1 kg (4.7 lbs.) with LCD
Enclosure Ratings
NEMA 4X / IP66
www.emerson.com/ams
8
AMS 9420 Wireless Vibration Transmitter
July 2017
Performance Specifications
ElectroMagnetic Compatibility (EMC)
Meets all relevant requirements of EN 61326.
Measurement Accuracy
RMS Velocity5:
+/- 5% from 10 Hz to 800 Hz
+/-3 dB from 2 Hz to 1000 Hz
PeakVue Impacting
+/- 5% from 2000 Hz to 10 kHz
+/- 3 dB from 1000 Hz to 20 Khz
Temperature: +/- 2°C
Measurement Precision
Vibration: +/- 0.2 dB
Temperature: +/- 2°C
Self Calibration
The analog-to-digital measurement circuitry automatically self-calibrates for
each update by comparing the dynamic measurement to internal reference
elements
Vibration Effect
No loss in functionality when tested per the requirements of IEC60770-1 with
high vibration level (10 Hz to 10 KHz) and up to 50g acceleration
RF Output Power (based on maximum device
output power of 6.3 mW)
Antenna Type
Max Gain
Max EIRP
Standard Long-Range
2.0 dBi
10 mW
Extended Range
4.5 dBi
18 mW
(3) Operating life with a single SmartPower Module is highly dependent on user configuration. Values shown are for operation at an ambient temperature of 21°C (70°F) as part of a
well-formed wireless network. Daily measurements are thumbnail spectra. Continuous exposure to extreme temperatures may significantly reduce operating life. Older revisions
exhibit a maximum power module life of 2 years at room temperature with a 54 minute burst rate. Actual results depend on the installation process.
(4) Burst rates over 60 minutes are configured using the "PowerSave" mode.
(5) Measurement accuracy is the absolute accuracy of the measurement relative to a known, calibrated excitation for WirelessHART devices. Values shown represent the expected
performance operating under steady-state conditions (20°C with no external interference).
Sensor and Connections
A0394 Sensor Series
Nominal Sensitivity
25 mV/g (2.5 mV/m/s2)
Frequency Range
96 to 600 Kcpm (1.6 to 10 kHz)
Amplitude Range
± 100 g (± 980 m/s2)
Broadband Resolution
3 mg rms (0.03 m/s2 rms)
Settling Time
≤ 2 sec
Temperature Range
-40 to +121°C (-40 to +250°F)
Weight
23 gm (0.81 oz)
Sensor Type
Low profile, side exit integral cable
www.emerson.com/ams
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AMS 9420 Wireless Vibration Transmitter
July 2017
Terminal Block Connections
Two options for Terminal Block
For SmartPower Module
Configuration 1: Single Vibration
Sensor
Connector 1: Red wire
Connector 2: White wire
Connector 3: Open
Connector 4: Black wire
Configuration 2: Single Vibration
Sensor with
Temperature
Connector 1: Red wire
Connector 2: White wire
Connector 3: Green wire
Connector 4: Black wire
Configuration 3: Two Vibration
Sensors
Connector 1: Red wires (2 total)
Connector 2: White wire (Sensor 1)
Connector 3: White wire (Sensor 2)
Connector 4: Black wires (2 total)
HART
Connection Connectors 5 & 6
External Power
Connector 7: Negative
Connector 8: Positive
www.emerson.com/ams
For External DC Line Power
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AMS 9420 Wireless Vibration Transmitter
July 2017
Product Certification and Registrations
General Certifications
Approved Manufacturing Locations
Emerson Process Management
Knoxville, Tennessee USA
Telecommunication Compliance
2.4 GHz WirelessHART
FCC ID: LW2RM2510
IC ID: 2731A-RM2510
ATEX Directive (94/9/EC)
Emerson Process Management complies with the ATEX Directive
Compliant to Electro Magnetic Compatibility (EMC) (2004/108/EC)
All Models conforming to the following standards: EN 61326-1
Country
Restriction
Bulgaria
General authorization required for outdoor use and public service
Italy
If used outside of own premises, general authorization is required
Norway
May be restricted in the geographical area within a radius of 20 km from the center
of Ny-Alesund
Romania
Use on a secondary basis. Individual license required
Radio and Telecommunications Terminal
Equipment Directive (R&TTE)(1999/5/EC)
Emerson Process Management complies with the R&TTE Directive
Canadian Standards Association (CSA)
General Safety Standard Certification conforming to the following standards:
CSA Std. C22.2 No. 61010-1-4 Safety Requirements for Electrical Equipment for
Measurement, Control and Laboratory Use, Part I: General Requirements (Second
Edition) ISA S82.02.01 2nd (IEC 61010-1 Mod)
Safety Standards for Electrical and Electronic Test, Measuring, Controlling and
Related Equipment – General Requirements
ANSI/UL Sta. 61010-1 Electrical Equipment for Measurement, Control and
Laboratory Use: Part 1 General Requirements (Second Edition)
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AMS 9420 Wireless Vibration Transmitter
July 2017
Hazardous Location Certification3 (Rev 4 and 5)
US/Canada
Ex ia IIB T4 Ga
AEx ia IIB T4 Ga
Class I, Division 1, Groups C & D
Ex ic IIC T4 Gc
AEx ic IIC T4 Gc
Class I, Division 2, Groups A, B, C & D
Enclosure Type 4X / IP66
ATEX
II 1 G Ex ia IIB T4 Ga
II 3 G Ex ic IIC T4 Gc
IECEx
Ex ia IIB T4 Ga
Ex ic IIC T4 Gc
Intrinsically safe only when used with Emerson Battery Pack Model A0701PBU or 701PBKKF. Consult factory for further information on approvals including additional
country-specific approvals. Also a non-rated version of the AMS 9420 is available, which can be operated with external line-power (10-28V DC) .
(3) Every effort is made to reflect current status. Consult factory for most recent information.
AMS 9420 dimensional drawing with long-range
and extended range antennas. Dimensions are in
mm (inches).
www.emerson.com/ams
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AMS 9420 Wireless Vibration Transmitter
July 2017
Are You Wireless?
As any plant manager will tell you, you can’t improve something
if you can’t measure it. Improved access to information provides
the opportunity to reduce operating costs while improving
quality, throughput, and availability. Add to that the expanding
requirement to certify compliance with new environmental and safety standards. This all points to the need for increased
monitoring, yet many managers still believe that the costs outweigh the benefits.
With wired systems, that may have been the case; however,
wireless networks remove traditional barriers and redefine the cost equation. A wireless network can substantially reduce
engineering, material, and implementation costs, and those
cost savings are just the beginning.
Imagine what you can do with the additional information.
Wireless technology can reduce – if not eliminate – the “blind
spots” in your plant, while empowering mobile workers by providing needed information. The AMS 9420 provides
predictive diagnostics for your essential production assets
from virtually any location. The result is increased process
uptime, improved consistency, and reduced risk of abnormal
situations. As more and more plants are turning to wireless
solutions, the question is “Are You Wireless?”.
An AMS 9420 is an easy addition to any existing wireless network.
©2017, Emerson. All rights reserved.
Emerson
Reliability Solutions
835 Innovation Drive
Knoxville, TN 37932 USA
+1 865 675 2400
www.emerson.com/ams
The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the
property of their respective owners.
The contents of this publication are presented for informational purposes only, and while every
effort has been made to ensure their accuracy, they are not to be construed as warranties or
guarantees, express or implied, regarding the products or services described herein or their
use or applicability. All sales are governed by our terms and conditions, which are available on
request. We reserve the right to modify or improve the designs or specifications of our products
at any time without notice.
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