407119A Datasheet, PDF (5/12 Pages) Extech Instruments Corporation. – Heavy Duty Hot Wire CFM Thermo-Anemometer

Operation
Initialization and Zero procedures (please follow these steps before use)
Important Note: The meter’s probe locking switch must
TOP VIEW OF METER
be in the locked position (with the probe inserted) for
the meter to turn on and operate correctly. Refer to the
accompanying diagram or the diagram at the top of the
meter for switch orientation.
For the best accuracy and for proper operation, the
LOCKED Position
following steps must be performed.
1. Connect the sensor to the input jack on top of the
meter by first unlocking the sensor jack and then
inserting the sensor plug. Lock the sensor jack after
the probe is inserted.
UNLOCKED Position
2. Press the POWER button to turn on the meter. The meter will perform a self-test during
which the display will count down from 9999 to 0000.
3. Select the air velocity function using the FUNCTION button. The LCD will display the
most recently selected unit of measure for air velocity.
4. To change the temperature units of measure (C/F), use the advanced programming
mode discussed later in this manual.
5. Momentary presses of the UNIT button changes the air velocity units. The LCD will
reflect the selection.
6. Place the sensor cover in the up (ZERO) position (see diagram below).
7. Open the telescoping sensing antenna to a convenient length.
8. Place the sensor in the area to be measured and allow a short time for it to stabilize to
the ambient temperature.
9. To Zero the meter display, press and hold the ZERO button until the second beep.
Warning! Do not touch the air velocity or temperature thermistors inside the sensor head
while moving the sensor cover.
5
Model 407119A Version 5.0 October 2005