TM_ELF-D_R1C
EBTRON
, Inc. 1663 Hwy. 701 S., Loris SC 29569
•
Toll Free: 800.2
EBTRON
(232.8766)
•
Fax: 843.756.1838
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Internet:
EBTRON
.com
3
ELF - E
LECTRONIC
L
OW
F
LOW
A
IRFLOW
/T
EMPERATURE
M
EASUREMENT
ELF
DUAL ANALOG OUTPUT
/D
SERIES
ADVANCED TECHNOLOGY
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EBTRON
Advanced Thermal Dispersion
(TD) airflow measurement technology
ensures accurate, repeatable measure-
ment from zero flow (still air).
•
Superior performance compared to con-
ventional differential pressure- based pitot
technology in challenging small duct and
VAV box applications.
•
Sensors are factory calibrated from 0-
3,000 FPM to volumetric airflow stan-
dards.
•
True volumetric airflow rate using inde-
pendent sensors.
•
Airflow and temperature outputs.
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Highest quality/stability hermetically
sealed "bead-in-glass" thermistors.
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Advanced industrial grade components
and robust microprocessor based design
ensures accuracy, stability and long term
reliability.
•
Convenient field-selectable analog output
signal options for airflow, equivalent veloc-
ity pressure and full scale
flow/temperature ranges.
•
Integrated mounting bracket simplifies
field installation.
Figure 1. EBTRON ELF/D Electronic Low Flow Measurement Station
OVERVIEW
The
EBTRON
ELF/D Series electronic low flow thermal dispersion
dual analog output airflow and temperature measurement station
features unique sensors designed for precise measurement and
control of airflow or equivalent velocity pressure and temperature in
small duct (16 inch max) and VAV box applications. Simple and flex-
ible analog output options permits interface to virtually all modern
building automation systems (BAS).
EBTRON
’s proprietary flow loss compensation techniques eliminate
inaccuracies typically associated with small duct and low airflow
measurement. Traditional measurement techniques produce read-
ings that are greater than actual flow due to the inherently large
ratio of duct wall surface to duct free area. The ELF/D uses a sin-
gle factory calibrated probe equipped with one or two sensor nodes,
depending on application.
ELF airflow sensors use high quality “bead-in-glass” thermistors to
determine the airflow rate and temperature at each sensing loca-
tion. The sensor relates the thermal transfer rate of a heated ele-
ment to airflow rate. As the velocity across the sensor increases, the
thermal transfer rate increases. Accuracy is ensured through indi-
vidual sensor characterization over a range of 0 to 3,000 FPM (0 to
15.24 m/s) in wind tunnels calibrated to volumetric airflow stan-
dards. Accuracy is percent of reading (not percent of full scale)
throughout the entire calibrated range. Convenient field selectors
permit selection of airflow or equivalent velocity pressure measure-
ment, and four output scaling ranges. A flow integration filter is
standard to optimize system response, but can be omitted for cus-
tom applications (refer to Ordering Guide in this document for
option codes). Analog outputs of 0-10/2-10VDC* are provided.
Equivalent volumetric flow can be determined by simply applying an
appropriate conversion formula. Each ELF airflow measurement
station includes a factory calibrated sensor probe and an integral
dedicated transmitter and mounting bracket.
1
Minimum analog output is 30 mV.