TM_ELF-D_R1C
ELF - E
LECTRONIC
L
OW
F
LOW
A
IRFLOW
/T
EMPERATURE
M
EASUREMENT
ELF
DUAL ANALOG OUTPUT
/D
SERIES
EBTRON
, Inc. 1663 Hwy. 701 S., Loris SC 29569
•
Toll Free: 800.2
EBTRON
(232.8766)
•
Fax: 843.756.1838
•
Internet:
EBTRON
.com
8
ELF/D PREPARATION FOR USE
The ELF/D provides two separate linear analog outputs corresponding to measured airflow (or equivalent velocity pres-
sure) and temperature. The airflow analog output can be set for either air flow or equivalent velocity pressure measure-
ment with four field selectable full scale range options. Temperature output is set for a full scale range of 30 to 160°F
(-1.1 to 71.1°C).
Preparation for use consists of connecting 24VAC input power and analog output signal wires from the ELF/D to the BAS
interface, and if required, setting the ELF/D analog output CONFIG switch options (measurement mode, analog output
signal type and full scale measurement range options).
ELF/D INTERCONNECTIONS
The ELF/D is equipped with a 4-conductor plenum rated 18 AWG interconnecting cable for power and analog output inter-
face to customer equipment. Connect 24 VAC power and analog output to customer interface as outlined in the follow-
ing paragraphs. Refer to Figure 5 and the following ELF/D cable color code descriptions:
Red
24 VAC power
Black* Common ELF Power/Signal Ground (for 24 VAC and for analog output)
White
Airflow Analog output signal
Green
Temperature Analog output signal
*CAUTION
The ELF is equipped with a common 24VAC ground and common analog output signal
return. EBTRON strongly recommends that the BAS control interface be connected to
each ELF analog output using TWO separate wires (twisted shielded pair) in order to
eliminate any potential voltage drop on the common (from the 24VAC return) that
would otherwise cause inaccurate readings.
CAUTION
To prevent damage to the ELF, deactivate 24 VAC power source until all connections
to the instrument are completed.
NOTE
The 24 VAC input ground (GND) connection is shared with the analog output signal
ground. If an isolated output is desired, a dedicated isolation transformer is required
to power the ELF.
ELF/D 24 VAC Power Connections
CAUTION
24 VAC power must be deactivated before making connections to the instrument.
The ELF requires a power source capable of providing 22.8 to 26.4 VAC at 5 VA. Connect 24VAC power between the red
wire and black wire as shown in Figure 5.