OPERATING INSTRUCTIONS
CL 326
DIGITAL THERMOMETER
INTRODUCTION
This instrument is a 3½
digit, compact-sized portable
digital thermometer designed to use external K/J/T/E type
thermocouples as temperature sensor. Temperature indica-
tion follows Reference Temperature/Voltage Tables
(N.I.S.T. Monograph 175 Revised to ITS-90) for K/J/T/E
type thermocouples.
SAFETY INFORMATION
It is recommended that you read the safety and opera-
tion instructions before using the thermometer.
WARNING
To avoid electrical shock, do not use this instrument
when working voltages at the measurement surface over
24V AC or DC.
WARNING
To avoid damage or burns, do not make temperature
measurement in microwave ovens.
CAUTION
Repeated sharp flexing can break the thermocouple
leads. To prolong lead life, avoid sharp bends in the
leads, especially near the connector.
SPECIFICATIONS
ELECTRICAL
Temperature Scale:
Celsius or Fahrenheit user-selectable.
Measurement Range:
Thermocouple Range
K-TYPE (0.1°C)
-200°C to 1372°C,
-328°F to 1999°F
J-TYPE (0.1°C) -210°C to 1200°C,
-346°F to 1999°F
T-TYPE (0.1°C)
-200°C to 400°C,
-328°F to 752°F
E-TYPE (0.1°C)
-220°C to 1000°C,
-364°F to 1832°F
Calibration Range:
-210°C to 1372°C, (-364°F to 1999°F)
Auto range:
0.1°C /1°C , 0.1°F /1°F
Accuracy:
Accuracy is specified for operating temperatures over
the range of 18°C to 28°C (64°F to 82°F), for 1 year, not
including thermocouple error.
±(0.1% rdg + 1°C) on -60°C to 1372°C
±(0.1% rdg + 2°C) on -60°C to -220°C
±(0.1% rdg + 2°F) on -76°F to 1999°F
±(0.1% rdg + 4°F) on -76°F to -364°F
ENVIRONMENTAL
Ambient Operating Ranges:
0°C to 50°C (32°F to 122°F) <80% R.H.
Storage Temperature:
-20°C to 60°C (-4°F to 140°F) <70% R.H.
GENERAL
Display:
3½ digit liquid crystal display (LCD) with a maximum
reading of 1999.
Polarity:
Automatic,positive implied,negative polarity indication.
Overrange:
-OL is displayed.
Zero:
Automatic.
Reading Rate:
one time per second.
Low battery indication:
The “
” is displayed when the battery voltage drops
below the operating level.
Measurement rate
:
1 times/second.
Accuracy:
Stated accuracy at 23°C±5°C, <75% R.H.
Input Connector:
Accepts standard miniature thermocouple connectors
(flat blades spaced 7.9mm, center to center).
Battery Life:
100 hours typical with carbon zinc battery.
Auto power off:
The meter key switch inactive for more than 70 minutes.
Temperature Coefficient:
0.1 times the applicable accuracy specification per °C
from 0°C to 18°C and 28°C to 50°C (32°F to 64°F and
82°F to 122°F).
Input Protection:
24V dc or 24V ac rms maximum input voltage on any
combination of input pins.
Maximum Differential Common Mode Voltage
(Maximum Voltage between T1 and T2 during mea-
surement):
1volt.
Dimensions:
195mm(H) x 92mm(W) x 53mm(D).
Weight:
approx. 9 oz. (250g) including battery.
°C /°F Selecting the Temperature Scale
Readings is displayed in either degrees Celsius(°C) or
degrees Fahrenheit(°F).
When the thermometer is turned on, it is set to the tem-
perature scale that was in use when the thermometer
was last turned off.
To change the temperature scale, press the °C or °F key.
“
” Button
Press “
” button to toggle on and off of backlight.
The backlight will switch-off automatically after 30
seconds.
HOLD Mode
Pressing the HOLD key to enter the Data Hold mode,
the “HOLD” annunciator is displayed.
When HOLD mode is selected, the thermometer held
the present readings and stops all further measurements.
Pressing the HOLD key again to cancel HOLD mode
causing thermometer to resume taking measurements.
K/J/T/E Input Thermocouple Type
The TYPE key switch the input circulating selects the
K/J/T/E type thermocouple as input.
T1 T2/T1-T2 Input Selection
The input selection indicates which input is selected; T1
thermocouple, T2 thermocouple or the difference
between the two thermocouples (T1-T2).
When the thermometer is turned on, it is set to the tem-
perature input that was in use when the thermometer
was last turned off.
