To change the units, press the UNITS/LOC key. The selected
units will remain in memory even when the power is shut off.
This way, your preference will always be displayed after the ini-
tial selection.
Display Hold
There may be situations where you want to temporarily retain
a reading. The Model 485 provides a display hold function which
freezes the current reading and holds the reading until cleared.
To activate this function, momentarily press the HOLD/MEMO-
RY key when the reading you want is displayed. A HOLD indi-
cator will appear in the display to indicate that the reading
shown is frozen. To return to normal operation, press the
HOLD/MEMORY key again. The HOLD indicator will disappear
and the current temperature and humidity readings will again be
shown.
Dew Point and Wet Bulb Temperatures
The Model 485 provides calculated dew point and wet bulb
temperatures. To display the dew point temperature, press the
DP/WB/STORE key. The large display will show the dew point
temperature in the selected units. The %RH indicator will be
extinguished and the smaller lower left display will show “dP” to
indicate dew point measurement. To display the wet bulb tem-
perature, press the DP/WB/STORE key again. The lower left dis-
play will now display “bt” to indicate wet bulb temperature. To
restore the display to %RH, press the DP/WB/STORE key again.
The %RH indicator will be illuminated and the relative humidity
and ambient temperature will again be displayed.
Min-Max Readings
A minimum and maximum reading function is provided by the
model 485. This will save the minimum and maximum tempera-
ture and relative humidity readings. To display the minimum
temperature and relative humidity readings press and hold the
MIN key. While the key is depressed the minimum recorded
readings will be displayed. To return to normal operation,
release the key. Likewise, to display the maximum readings,
press and hold the MAX key; release when done. To clear the
MIN/MAX memory, press both the MIN and MAX keys simulta-
neously. The display will display “----” while the memory is
being cleared. When the switches are released the MIN/MAX
memory begins storing the current minimum and maximum val-
ues. The minimum and maximum values are stored in non-
volatile memory which retains the minimum and maximum val-
ues even when the power is off.
Memory Function
A memory function is included in the Model 485 that allows
you to store up to 25 humidity and temperature readings. The
samples are stored in nonvolatile memory so the samples are
retained even when the power is off.
Entering Memory Mode
To enter memory mode, press and hold the HOLD/MEMORY
key until the MEM indicator appears in the display. The key can
then be released. The active memory location will be briefly dis-
played, starting initially with “01”, then humidity will be dis-
played.
Storing Readings
To store a reading, press the DP/WB/STORE key. The read-
ings will be stored in the previously indicated memory location
and a beep will sound to indicate the reading has been saved.
As each reading is saved, the memory location is advanced to
the next location and briefly displayed in the lower left display.
Viewing Stored Readings
To view the contents of memory, the unit must be in the mem-
ory mode. To enter the view mode, press the UNITS/LOC but-
ton. The HOLD indicator will then be displayed with the MEM
indicator to indicate that the memory values are being displayed
rather than the current readings, and the location number will be
briefly displayed. Each time the UNITS/LOC button is pressed
the memory location is advanced, and the new location is briefly
displayed. If the button is held down, the location will automat-
ically increment until the button is released. This operation may
be used to select a particular memory location to store the next
reading. To resume temperature and humidity measurements,
press the HOLD/MEMORY button. The HOLD indicator will dis-
appear and the display will resume displaying the current mea-
surements. The last viewed memory location will remain as the
location in which the next sample will be stored.
Clearing Memory
The memory may be cleared of all previously stored values by
pressing and holding the DP/WB/STORE key, then simultane-
ously pressing the ON/OFF key. During the clearing operation “-
---” will be displayed. When the memory is cleared, the current
readings will be displayed and the memory location will be set
to “01”.
Exiting Memory Mode
To exit memory mode, press the HOLD/MEMORY key. The
memory indicator will disappear. All values stored in memory will
be retained for later viewing.
Low Battery Indicator
A weak battery may cause improper operation or inaccurate
measurements. A low battery indicator is provided on the dis-
play to show when the battery needs to be replaced. Although
the unit may appear to function and read properly, the accuracy
of the readings cannot be guaranteed when the “LOW BAT”
indicator is illuminated. Replace the battery with a fresh one. Do
not leave an exhausted battery in the unit due to potential bat-
tery leakage.
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: 219/872-9057 e-mail: info@dwyer-inst.com
Lit-By Fax: 888/891-4963
