Efficient Plant July 2018 - 33

instrumentation

Choose the Correct
Accelerometer
Answering eight questions on how and where an accelerometer is to be used
simplifies the selection process. Photo: IMI Sensors

1. WHAT TYPE OF DATA IS REQUIRED?
 Raw or overall data: An accelerometer's VAC signal is a dynamic
signal on which frequency analysis can be performed while a vibration transmitter's continuous 4-to-20-mA signal of overall values
can connect directly with PLC, DCS, and SCADA systems.
 Acceleration, velocity, or displacement: The appropriate measurement range depends on the frequency of the measured vibration.
+ displacement: 0 to 10 Hz
+ velocity: 10 to 2,000 Hz
+ acceleration: greater than 2,000 Hz.
2. WHAT IS THE VIBRATION AMPLITUDE?
 The maximum amplitude of the measured vibration will determine
the sensor's measurement range.
+ common accelerometer ranges: 10, 50, 100, and 500 g
+ common vibration-transmitter ranges: 0 to 1 and 0 to 2 ips;
0 to 5 and 0 to 10 g
3. WHAT IS THE VIBRATION FREQUENCY?
 Low-frequency response: Most industrial sensors will have a limit
near 0.2 Hz.
 High-frequency response: Sensors have a resonant frequency at
which the signal is amplified, leading to sensitivity changes and
possible saturation. To combat saturation, most industrial accelerometers have single- or double-pole RC filters.
4. WHAT IS THE TEMPERATURE OF THE

ENVIRONMENT?

 Determine the highest and lowest temperatures to which the sensor
will be subjected.
+ -65 F to 250 F: Most general-purpose industrial sensors with
integral electronics can operate in this range.
+ 250 F to 325 F: High-temperature sensors with special integral

JULY 2018

SELECTING ACCELEROMETERS for specific applications need
not be difficult. Meredith Christman of IMI Sensors, Depew, NY
(pcb.com), says the process basically involves answering eight questions.
- Jane Alexander, Managing Editor

electronics are available since higher temperatures can harm
built-in electronics of general-purpose units.
+ >325 F: Charge-mode designs without built-in electronics are
available.

5. WILL THE UNIT BE SUBMERSED IN LIQUID?
 Depths <1,700 ft.: Sensors with integral cables can be permanently
submersed without additional testing.
 Depths >1,700 ft.: Sensor should be pressure tested for one hour.
6. WILL THE UNIT BE EXPOSED TO CHEMICALS?
 Sensors: Industrial designs feature corrosion-resistant
stainless-steel housings.
 Cables/connectors: Check a chemical-compatibility chart. With corrosive chemicals, use PTFE cable with non-corrosive connectors.
7. DO YOU WANT PRECISION OR LOW COST?
 Calibration: Precision sensors receive a full calibration. Low-cost
designs receive single-point calibration.
 Tolerances: Precision sensors have tighter tolerances on specifications such as sensitivity, i.e., sensitivity tolerance of ±5% versus
±10% for low-cost designs.
8. ARE SPECIAL APPROVALS REQUIRED?
 Most industrial sensors can be certified as intrinsically safe for potentially explosive areas. Compare the type of approval needed with
a sensor's published approvals to ensure it meets your particular
requirements. EP

Meredith Christman is a product-marketing manager with IMI
Sensors, a division of PCB Piezotronics, Depew, NY. Learn more about a
range of condition-monitoring solutions at pcb.com.
EFFICIENTPLANTMAG.COM |

33


http://www.pcb.com http://www.pcb.com http://www.EFFICIENTPLANTMAG.COM

Table of Contents for the Digital Edition of Efficient Plant July 2018

Editorial
Implementations
Find Gold In Sustainable Manufacturing
Troubleshoot Control Systems Effectively
Automation Accelerates Beer Production
Lubed Chains Live Long Lives
SAP: Use These Tools For PM Compliance
Protect Your Site From Cyber Attacks
Build The Value Of Your CM Program
Choose The Correct Acclerometer
On The Floor
Intelligent Design Process Delivers For Substation
Solution Focus
Old Compressor Gets New Lease On Life
Products
Index
Showcase
Seeking Reliability
Efficient Plant July 2018 - Cover1
Efficient Plant July 2018 - Cover2
Efficient Plant July 2018 - 1
Efficient Plant July 2018 - 2
Efficient Plant July 2018 - 3
Efficient Plant July 2018 - 4
Efficient Plant July 2018 - 5
Efficient Plant July 2018 - Editorial
Efficient Plant July 2018 - 7
Efficient Plant July 2018 - Implementations
Efficient Plant July 2018 - 9
Efficient Plant July 2018 - Find Gold In Sustainable Manufacturing
Efficient Plant July 2018 - 11
Efficient Plant July 2018 - 12
Efficient Plant July 2018 - 13
Efficient Plant July 2018 - 14
Efficient Plant July 2018 - 15
Efficient Plant July 2018 - 16
Efficient Plant July 2018 - 17
Efficient Plant July 2018 - Troubleshoot Control Systems Effectively
Efficient Plant July 2018 - 19
Efficient Plant July 2018 - 20
Efficient Plant July 2018 - 21
Efficient Plant July 2018 - Automation Accelerates Beer Production
Efficient Plant July 2018 - 23
Efficient Plant July 2018 - 24
Efficient Plant July 2018 - 25
Efficient Plant July 2018 - 26
Efficient Plant July 2018 - Lubed Chains Live Long Lives
Efficient Plant July 2018 - 28
Efficient Plant July 2018 - 29
Efficient Plant July 2018 - SAP: Use These Tools For PM Compliance
Efficient Plant July 2018 - Protect Your Site From Cyber Attacks
Efficient Plant July 2018 - Build The Value Of Your CM Program
Efficient Plant July 2018 - Choose The Correct Acclerometer
Efficient Plant July 2018 - On The Floor
Efficient Plant July 2018 - 35
Efficient Plant July 2018 - Solution Focus
Efficient Plant July 2018 - 37
Efficient Plant July 2018 - 38
Efficient Plant July 2018 - 39
Efficient Plant July 2018 - Old Compressor Gets New Lease On Life
Efficient Plant July 2018 - 41
Efficient Plant July 2018 - Products
Efficient Plant July 2018 - 43
Efficient Plant July 2018 - 44
Efficient Plant July 2018 - 45
Efficient Plant July 2018 - Index
Efficient Plant July 2018 - Showcase
Efficient Plant July 2018 - Seeking Reliability
Efficient Plant July 2018 - Cover3
Efficient Plant July 2018 - Cover4
https://www.nxtbook.com/atp/MaintenanceTechnology/epjulyaug2020
https://www.nxtbook.com/atp/MaintenanceTechnology/epjune2020
https://www.nxtbook.com/atp/MaintenanceTechnology/epmay2020
https://www.nxtbook.com/atp/MaintenanceTechnology/epapril2020
https://www.nxtbook.com/atp/MaintenanceTechnology/epmarch2020
https://www.nxtbook.com/atp/MaintenanceTechnology/epfeb2020
https://www.nxtbook.com/atp/MaintenanceTechnology/epjan2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epnovdec2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epseptoct2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epmay2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epapril2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epmarch2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epfebruary2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epjanuary2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epdecember2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epnovember2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epoctober2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epseptember2019
https://www.nxtbook.com/atp/MaintenanceTechnology/epaugust2018
https://www.nxtbook.com/atp/MaintenanceTechnology/0818schneider
https://www.nxtbook.com/atp/MaintenanceTechnology/epjuly2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epjune2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epmay2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epapril2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epmarch2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epfebruary2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epjanuary2018
https://www.nxtbook.com/atp/MaintenanceTechnology/epdecember2017
https://www.nxtbook.com/atp/MaintenanceTechnology/epnovember2017
https://www.nxtbook.com/atp/MaintenanceTechnology/epoctober2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtsept2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtaugust2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtjuly2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtjune2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtmay2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtapril2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtmarch2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtfebruary2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtjanuary2017
https://www.nxtbook.com/atp/MaintenanceTechnology/mtdecember2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtnovember2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtoctober2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtseptember2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtaugust2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtjuly2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtjune2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtmay2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtapril2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtmarch2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtfebruary2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtjanuary2016
https://www.nxtbook.com/atp/MaintenanceTechnology/mtdecember2015
https://www.nxtbook.com/atp/MaintenanceTechnology/mtnovember2015
https://www.nxtbook.com/atp/MaintenanceTechnology/mtoctober2015
https://www.nxtbook.com/atp/MaintenanceTechnology/mtseptember2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTAugust2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTJuly2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTJune2015
https://www.nxtbook.com/atp/MaintenanceTechnology/M
https://www.nxtbook.com/atp/MaintenanceTechnology/0415endress
https://www.nxtbook.com/atp/MaintenanceTechnology/MTApril2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTMarch2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTFebruary2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTJanuary2015
https://www.nxtbook.com/atp/MaintenanceTechnology/MTDecember2014
https://www.nxtbook.com/atp/MaintenanceTechnology/MTNovember2014
https://www.nxtbook.com/atp/MaintenanceTechnology/MTOctober2014
https://www.nxtbook.com/atp/MaintenanceTechnology/MTSeptember2014
https://www.nxtbook.com/atp/MaintenanceTechnology/MTAugust2014
https://www.nxtbook.com/atp/MaintenanceTechnology/MTJuly2014
https://www.nxtbookmedia.com