Extech Instruments RH300 User manual

User's Guide
Digital Psychrometer
Models RH300 and RH305 (kit)
Introduction
Congratulations on your purchase of the Extech RH300 Digital Psychrometer. This device
measures Humidity, Air Temperature, Dew Point temperature and Wet Bulb temperature.
Advanced features include External Temperature Measurement (with optional probe), Data
Hold, selectable Auto Power Off, and MAX/MIN/Average reading. Careful use of this meter
will provide years of reliable service.
HOLD
RESET
MX/MN
RESET
MX/MN
T/DP
T2
T1
/WB
ON/OFF
oo
C/ F

RH300 V1.4 11/04
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Specifications
Function Range and Resolution Accuracy
Humidity 0.0 to 100.0% RH ±3% RH (10 to 90%) @ 23oC
Temperature (internal) -4.0 to 122.0oF (-20 to 50oC) ±1.8oF (±1oC)
Temperature (external) -4.0 to 158.0oF (-20 to 70oC) ±1.8oF (±1oC)
Display Triple LCD
Sensor Type Humidity: Precision capacitance sensor
Temperature: Thermistor
Response Time 60 seconds typical
Dew Point -90.4 to 122.0oF (-68 to 50oC) (calculated from RH and Air
temperature measurements)
Wet Bulb -6.88 to 122.0oF (-21.6 to 50oC) (calculated from RH and Air
temperature measurements)
Operating Conditions -4 to 122oF (-20 to 50oC); < 99% RH non-condensing
Storage Conditions -40 to 185oF (-40 to 85oC); <99% RH non-condensing
Power Supply 2 x 1.5V ‘AAA’ batteries
Battery Life Approx. 80 hours
Dimensions / Weight 7 x 1.9 x 1” (178.5 x 48.8 x 25.2mm); 4.9 oz. (140g)
Meter Description
1. Humidity Sensor & Air Temperature Sensor
2. Triple LCD Display
3. ON/OFF button
4. T1-T2/Dew Point/T1 button
5. °F/°C select
6. MIN/MAX/RESET button
7. T2-DP/Wet Bulb/T2 button
8. HOLD button
9. T2 Probe Jack
Note: The battery compartment is located
on the rear of the instrument
HOLD
RESET
MX/MN
T/DP
T2 T1
/WB
ON/OFF
oo
C/ F
1
2
3
4
56
7
8
9

RH300 V1.4 11/04
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/WB
T2
T/DP
T1
1
2
3
4
56
7
8
9
10
11
Display Description
1. Relative Humidity %
2. T1
3. T1-T2
4. Dew Point
5. Wet Bulb
6. T2-Dew Point
7. °C/°F
8. T2
9. Maximum
10. Minimum
11. Low Battery/Hold
Operation
Open the Protective Sensor Cap
Twist the protective sensor cap, located at the top of
the meter, counter-clockwise a quarter of a turn to
expose the sensor
Plug in the optional external temperature probe (if
needed).
Turn Power ON or OFF
Press the ON/OFF button to turn power on or off. The meter will perform a short self-test
when turned on.
Taking measurements
1. Hold the probe in the area to be tested.
2. Allow adequate time for readings to stabilize.
3. The Relative Humidity measurement appears in
the top display.
4. Pressing the button toggles the lower left
display between T1-T2 (internal temperature-
external temperature), DP (Dew Point), and T1
(internal temperature).
5. Pressing the button toggles the lower right
display between T2-DP (external temperature-
Dew Point), WB (Wet Bulb), and T2 (external
temperature).
Note: If the external probe is not connected, T1-T2, T2-DP, and T2 measurements will not
be displayed.
Selecting temperature units of measure (C/F)
Press and hold the oC/oF button momentarily to toggle the temperature units.
CLOSE OPEN

RH300 V1.4 11/04
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RESET
MX/MN
RESET
MX/MN
RESET
MX/MN
RESET
MX/MN
/WB
T2
T/DP
T1
Wet Bulb and Dew Point measurements
1. To read the Wet Bulb measurement, press the button until the symbol Wb
appears in the lower right display. Note: T2 will not be displayed unless the external
probe is connected.
2. Wet Bulb temperature is now displayed.
3. To read the Dew Point measurement, press the button until the symbol DP
appears in the lower left display .
4. Dew Point temperature is now displayed.
Minimum (MIN) Maximum (MAX) Function
The MIN/MAX mode allows the user to view only the lowest (MIN) or highest (MAX)
readings. Press the button once and MIN appears on the display. The display is
now showing the lowest humidity and temperature reading in memory. Press the
button again and MAX appears on the display. The display is now showing the maximum
humidity and temperature readings in memory. To exit the MIN/MAX mode, press the
button again and the MIN and MAX icons disappear. To clear the current min/max
readings in memory, press and hold the button for more than two seconds.
Data Hold
Press the HOLD button momentarily to freeze the displayed reading. The 'HLD' icon will
appear on the upper right-hand side of the display. Press the HOLD button again to return
to normal operation.
Automatic Power OFF
The meter automatically shuts off after a programmed period of time. The default time is 10
minutes. To program the time period, press down the HOLD button while turning the meter
on. Continue to hold down both buttons and the meter will cycle through the selectable
power-off times: n, 2, 5, 10, 20, 40 or 60 minutes. “n” disables the auto power off function.
When the desired power-off time appears in the display, release both buttons to select the
time and return to normal operation.
Error Messages
An error message will appear on the display if the meter fails an internal diagnostic test.
1. ER1: Relative Humidity failure. Repair/replacement is necessary.
2. ER2: Internal temperature failure. Repair/replacement necessary.
3. ER3: Reference resistance failure. Repair/replacement necessary.
4. ER4: Internal temperature is out of range.
5. ER5: External temperature is out of range.

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RESET
MX/MN
RESET
MX/MN
CALIBRATION
The following verification and calibration procedures require the 33% and 75% RH reference
bottles which are supplied with the Model RH305 kit.
Accuracy Verification
Checking the 33% or 75% RH Calibration
1. Insert meter’s sensor into the 33% or 75% salt reference bottle
2. Check the reading after 10 minutes
3. Verify that the reading is within the accuracy specification
Relative Humidity Calibration (33% and 75%)
33% Calibration
1. Ensure that “DP” and “WB” appear in the bottom displays before turning the meter
OFF.
2. Insert the meter sensor into the 33% salt reference bottle.
3. Allow the meter one hour to stabilize.
4. While holding down the °C/°F button, press and hold the ON/OFF button for 2 seconds
to enter calibration mode.
5. “32.8%” will flash on the LCD screen and “DP” and “WB” will display “_ _ _ _”. After 30
minutes, the flashing will stop to indicate that the 33% calibration is complete. Note: To
exit from the calibration procedure before completion, pressing the ON/OFF button will
turn the meter off.
6. Proceed to the 75% Calibration below.
75% Calibration
1. Insert the meter sensor into the 75% salt reference bottle.
2. Allow the meter one hour to stabilize.
3. Press and hold the button for 2 seconds to enter the 75% calibration.
4. “75.3%” will flash on the LCD. After 30 minutes, the flashing will stop to indicate that
the 75% calibration is complete.
5. Turn power off. Calibration is now complete.
Note: If the salt at the bottom of the calibration bottles appears dry, the bottles should be
replaced.

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
Support line [phone]
Technical support: Extension 200; E-mail: [email protected]m
Repair & Returns: Extension 210; E-mail: [email protected]
Product specifications subject to change without notice
For the latest version of this User’s Guide, Software updates, and other
up-to-the-minute product information, visit our website: www.extech.com
Maintenance
Cleaning and storage
1. The meter should be cleaned with a damp cloth and mild detergent when necessary.
Do not use solvents or abrasives.
2. Store the meter in an area with moderate temperature and humidity (refer to the
operating and storage range in the specifications chart earlier in this manual).
Battery Replacement
When the battery power falls low, the symbol will appear on the LCD. Replace the two
(2) 1.5 ‘AAA’ batteries by removing the rear battery compartment cover and accessing the
battery compartment. Observe polarity when placing the batteries in the compartment.
Ensure that the compartment cover is securely fastened when finished.
Warranty
EXTECH INSTRUMENTS CORPORATION warrants the basic instrument to be free of
defects in parts and workmanship for one year from date of shipment (a six month limited
warranty applies on sensors and cables). If it should become necessary to return the
instrument for service during or beyond the warranty period, contact the Customer Service
Department at [phone] EXTENSION 210 for authorization or visit www.extech.com for
more information. A Return Authorization (RA) number must be issued before any
product is returned to Extech. The sender is responsible for shipping charges, freight,
insurance and proper packaging to prevent damage in transit. This warranty does not apply
to defects resulting from action of the user such as misuse, improper wiring, operation
outside of specification, improper maintenance or repair, or unauthorized modification. Extech
specifically disclaims any implied warranties or merchantability or fitness for a specific
purpose and will not be liable for any direct, indirect, incidental or consequential damages.
Extech's total liability is limited to repair or replacement of the product. The warranty set forth
above is inclusive and no other warranty, whether written or oral, is expressed or implied.
Copyright ©2004 Extech Instruments Corporation.
All rights reserved including the right of reproduction in whole or in part in any form.

Manual del usuario
Sicrómetro Digital
Modelo RH300 y RH305 (kit)
Introducción
Felicitaciones por su compra del Sicrómetro digital RH300 de Extech Este dispositivo mide
humedad, temperatura del aire, temperatura de punto de rocío y temperatura de
termómetro de bulbo húmedo . Las características avanzadas incluyen medición de
temperatura exterior (con sonda opcional), retención de datos, apagado automático
optativo y lecturas MÁX / MIN/Promedio. El uso cuidadoso de este medidor le proveerá
muchos años de servicio confiable.
HOLD
RESET
MX/MN
RESET
MX/MN
T/DP
T2
T1
/WB
ON/OFF
oo
C/ F

RH300 V1.4 11/04
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Especificaciones
Función Escala y Resolución Precisión
Humedad 0.0 a 100.0% RH ±3% RH (10 a 90%) @ 23oC
Temperatura (interior) -20.0 a 50oC (-4 a 122.0oF) ±1oC (±1.8oF)
Temperatura (exterior) -20 a 70oC (-4.0 a 158.0oF) ±1oC (±1.8oF)
Pantalla LCD triple
Sensor tipo Humedad: Sensor de precisión para capacitancia
Temperatura: Termistor
Punto de rocío -68 a 50oC (-90.4 a 122.0oF)
Bulbo húmedo -21.6 a 50oC (-6.88 a 122.0oF)
Tiempo de respuesta 60 segundos típicamente
Condiciones de operación -20 a 50oC (-4 a 122oF); < 99% RH sin
condensación
Condiciones de almacenamiento -40 a 85oC (-40 a 185oF); <99% RH sin
condensación
Fuente de tensión 2 X 1.5V 'AAA’ baterías
Vida de la batería Aprox. 80 horas
Dimensiones / Peso 178.5 X 48.8 X 25.2mm(7 X 1.9 X 1”); 140 g. (4.9 oz)
Descripción del medidor
1. El sensor de la humedad y el sensor aéreo de la
temperatura
2. El despliegue triple de LCD
3. Botón ON/OFF
4. Botón T1-T2/Punto de rocío/T1
5. °F/°C. selector
6. Botón MIN/MÁX/RESTAURAR
7. T2-PR/bulbo húmedo/T2 (PR = Punto de rocío)
8. Botón Retención (HOLD)
9. T2 Teiete la entrada
Nota: El compartimiento de la batería se localiza atrás del
instrumento
HOLD
RESET
MX/MN
T/DP
T2 T1
/WB
ON/OFF
oo
C/ F
1
2
3
4
56
7
8
9

RH300 V1.4 11/04
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/WB
T2
T/DP
T1
Descripción del despliegue
1. Humedad relativa %
2. T1
3. T1-T2
4. Punto de rocío
5. Bulbo húmedo
6. T2- Punto de rocío
7. °C/°F
8. T2
9. Máximo
10. Mínimo
11. La batería baja /Retención
Operación
Abra la cubierta protectora del sensor
En la parte superior del medidor gire la cubierta
protectora del sensor un cuarto de vuelta contra reloj
para exponer el sensor.
Enchufe la sonda optativa para temperatura exterior (si
necesitado).
.
Encienda (ON) o apague (OFF),
Presione el botón ON/OFF para encender o apagar. El medidor realizará una corta prueba
interna al encender.
Toma de medidas
1. Sostenga la sonda en el área que desea probar
2. De suficiente tiempo para que la lectura se
estabilice.
3. La medida de humedad relativa se muestra en la
pantalla superior.
4. Al presionar el botón cambia la indicación
inferior izquierda entre T1-T2 (temperatura
interior/exterior), PR (punto de rocío) y T1
(temperatura interna)
5. Al presionar el botón cambia la indicación
inferior derecha entre T2-PR (temperatura exterior/punto de rocío), WB (bulbo
húmedo), y T2 (temperatura exterior)
Nota: Si no está conectada la sonda externa, no se mostrarán las medidas T1-T2, T2-PR
y T2.
Selección de unidades de medición de temperatura (C./°F)
Presione y sostenga momentáneamente el botón oC/oF para cambiar las unidades de
temperatura.
1
2
3
4
56
7
8
9
10
11
ABRA
CIERRE

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RESET
MX/MN
RESET
MX/MN
RESET
MX/MN
RESET
MX/MN
/WB
T2
T/DP
T1
Medidas de Bulbo húmedo y Punto de rocío
1. Para leer la medida de bulbo húmedo, presione el botón hasta que en la
pantalla inferior derecha aparezca el símbolo Wb. T2 no se demostrará a menos que
la tienta externa se conectará.
2. Se muestra la temperatura de bulbo húmedo.
3. Para leer la medida de Punto de rocío, presione el botón hasta que en la
pantalla inferior derecha aparezca el símbolo DP.
4. Se muestra la temperatura de Punto de rocío.
Función Mínimo (MIN) Máximo (MÁX)
El modo MIN/MÁX permite al usuario ver sólo las lecturas más baja MIN:) o más alta
MÁX). Presione una vez el botón . y MIN: aparece en la pantalla. La pantalla indica
ahora las lecturas de humedad y temperatura más bajas en la memoria. Presione de
nuevo el botón . y MÁX aparece en la pantalla. La pantalla indica ahora las lecturas
más altas de humedad y temperatura en la memoria. Para salir del modo MIN/MÁX,
presione de nuevo el botón y desaparecen los iconos MIN: y MÁX. Para borrar
las lecturas min./máx. de la memoria, presione y sostenga el botón durante más de
dos segundos.
Retención de datos
Presione el botón HOLD para congelar la lectura indicada. El icono 'HLD' aparece en la
parte superior derecha de la pantalla. Presione HOLD de nuevo para regresar a operación
normal.
Apagado automático
El medidor se apaga automáticamente después de un periodo programado. El tiempo
predeterminado es de 10 minutos. Para programar el tiempo de espera, presione el botón
Retención (HOLD) al encender el medidor. Continúe presionando ambos botones y el
medidor pasará por los tiempos disponibles para apagado: n, 2, 5, 10, 20, 40 ó 60
minutos. "n" desactiva la función de apagado automático. Cuando el tiempo de apagado
deseado aparezca en la pantalla, suelte ambos botones para seleccionar el tiempo y
regresar a operación normal.
Mensajes de error
Aparecerá un mensaje de error en pantalla si el medidor falla la prueba interna de
diagnóstico.
1. ER1: Falla de humedad relativa Es necesario reparar o reemplazar.
2. ER2: Falla de temperatura interior. Es necesario reparar o
reemplazar.
3. ER3: Falla de la resistencia de referencia . Es necesario reparar o
reemplazar.
4. ER4: La temperatura interior está fuera de escala.
5. ER5: La temperatura externa está fuera de escala.