Extech 445815 - Manual

User’s Guide

Model 445815

Humidity Alert II

Humidity Indicator with Dew Point and Programmable Hi/Lo %RH Alarms

Introduction

Congratulations on your purchase of Extech’s Humidity Alert II Remote Probe

Hygro-Thermometer. Humidity alarms warn when the %RH exceeds a pre-set HI
or LO limit. The remote probe conveniently mounts on the meter or extends for

measurements in ducts or remote locations. It also features Humidity and
Temperature adjustments. The unit can be wall-mounted or placed on a flat

surface using the fold-out stand. This professional meter, with proper care, will
provide years of safe reliable service.

Meter Description

1.

Temperature-Humidity Sensor

2.

%RH Display

3.

Dew Point Display

4.

Temperature Display

5.

%RH LED alarm

6.

Max/Min push button

7.

Reset push button

8.

Sensor cable storage

9.

Tilt Stand

10.

Humidity calibration adjust

11.

Temperature units switch (ºF/ºC)

12.

Temperature calibration adjust

13.

Wall hanger

14.

Battery compartment

15.

Audible Alarm ON/Off switch

Cautions



This device is not a toy and must not reach children’s hands. It contains
hazardous objects as well as small parts that the children could swallow. In

case a child swallows any of them, please contact a physician immediately



Do not leave batteries and packing material lying around unattended; they
can be dangerous for children if they use them as toys



In case the device is going to be unused for an extended period of time,
remove the batteries to prevent them from training



Expired or damaged batteries can cause cauterization on contact with the
skin. Always, therefore, use suitable hand gloves in such cases



See that the batteries are not short-circuited. Do not throw batteries into the

fire.

Copyright

©

2005-2015 FLIR Systems, Inc.

All rights reserved including the right of reproduction in whole or in part in any

form

ISO-9001 Certified

www.extech.com

V3.4 7/15

Operation

Preparation for use

Open the battery compartment by pushing the cover on the rear of the

instrument downward as indicated by the arrow. Remove the battery insulating
strip and the protective film cover on the LCD display.

Temperature Units

Select ºF or ºC units using the rear selection switch.

Audible alarm

Select or using the rear selection switch to turn the audible alarm on or

off.

Maximum / Minimum display

1.

Press the MAX/MIN button. The highest value measured since the Reset

button was last pressed appears on the display.

2.

Press the MAX/MIN button again to display the lowest value measured since
the Reset button was last pressed.

3.

Press the MAX/MIN button again to return to normal display operation.

Resetting (clearing) the MAX/MIN memory

1.

Press the MAX/MIN button to enter the MAX/MIN mode.

2.

Press and hold the RESET button for 1 second to clear the memory and

start recording new max/min values.

Setting the %RH Alarm Limits.

1.

Simultaneously Press and HOLD the MAX/MIN and RESET button until “HI”

and the stored HI %RH limit appears flashing.

2.

Press the RESET button to set the Hi %RH limit. Hold the button in for rapid
adjustment.

3.

Press the Max/Min button. “LO” and the stored LO %RH limit will appear

flashing

4.

Press the RESET button to set the LO %RH limit.

5.

Press the Max/Min button to turn on or off the alarm. The alarm icon

will

appear in the display when the alarm is active.

6.

Press and hold the RESET button to save the settings and exit the mode.

Alert

If %RH exceeds the HI limit or goes below the LO limit the alert will be

activated. The alert consist of two flashing ‘ALERT” icons in the upper display,
a flashing red light (for 60 seconds) and an audible buzzer (for 60 seconds)

Calibration

RH Calibration

1.

Insert meter’s sensor into a humidity chamber.
The reference should be 85% RH at 21°C.

2.

Check the reading after 1 hour.

3.

Adjust the RH calibration pot in ½ turn increments, waiting for the display to
update after each adjustment, until the reading is within the accuracy

specification.

Temperature Calibration

1.

Place the sensor in a stabilized environment of approximately 21°C.

2.

Check the reading after 1 hour.

3.

Adjust the temperature calibration pot in ½ turn increments, waiting for the

display to update after each adjustment, until the reading is within the
accuracy specification.

Battery Replacement

Open the battery compartment by sliding the battery cover on the rear of the

instrument downward as indicated by the arrow. Replace the 1.5V ‘AAA’ batteries
and replace the cover.

You, as the end user, are legally bound (

Battery ordinance

) to

return all used batteries and accumulators;

disposal with the

household garbage is prohibited!

You can hand over your used batteries / accumulators,

gratuitously, at the collection points for our branches in your
community or wherever batteries / accumulators are sold!

Disposal:

Follow the valid legal stipulations in respect of the

disposal of the device at the end of its lifecycle

Specifications

Range

Accuracy

Temperature

-10 to 60

o

C

14 to 140

o

F

+ 1.0

o

C within -10

o

C to 50

o

C

+ 1.8

o

F within 14

o

F to 122

o

F

Humidity

10% to 99%

+ 4% RH within 25% to 85% RH and 0 to
50

o

C or 32 to 122

o

F

Dew Point

-36 to 60

o

C

-32.8 to 140

o

F

+/-2

o

C. @ 20

o

C

+/-3.6

o

F @ 68

o

F

Battery

(2) 1.5V 'AAA' cell

Weight

6 oz (169g)

Dimensions

Display: 4.3x3.9x0.8” (109x99x20mm)
Probe: 0.57” (14.4mm) Dia.: 1.67”(42.4mm) L
Cable length 18” (457mm)

Note: If subjected to an electrostatic discharge the meter may
malfunction and require the user to perform a reset.