PASCO CI-6526 User Manual

Instruction Sheet
for the PASCO
Model CI-6526

Type K Temperature Sensor

Introduction

The PASCO Model CI-6526 Type-K Thermo­couple Temperature Sensor is designed
to be used with a PASCO CI com­puter interface or a PASPORT USB
interface with an Analog Adapter
(PS-2158). A thermocouple works
because junctions between dissimi­lar metals or alloys in an electrical circuit
give rise to an electromotive force or voltage if they
are at different temperatures. This type of thermo­couple is made from a chromel and alumel wire junc­tion.

Range

The tip of the 003-05590 Type-K Thermocouple
Probe can withstand temperatures between -180°C
and +1260°C. However, the insulation material that
covers all but the tip of the sensor has a maximum
temperature of +482°C. You can use the sensor to

insulation (maximum

temperature: +482°C)

tip (maximum

temperature: +1260°C)

012-05563D

low zero degrees Celsius. The Type-K Thermocouple
can be used in water and mild chemical solutions; but
it is well suited for dry measurements.

The sensor consists of the Type-K probe (Model
PS-2155) and the sensor electronics box. The sensor
box has a socket made from chromel and alumel that
is mounted very close to the AD595 integrated circuit
(IC). The IC provides the cold junction compensation
as long as the IC temperature is equal to the junction
temperature made by the socket and copper connec­tions. The overall output voltage-to-temperature ratio
is 10 milliVolts per degree Celsius. The output voltage
range is -2.000 (at

-200°C) to +10.000 Volts (at +1,000°C).

Temperature Range of

003-05590 Type-K Thermocouple Probe

measure high temperatures such as those in a candle
flame if you keep the insulated portion of the sensor
out of the flame.

The thermocouple characteristics are fairly linear from
zero degrees Celsius up to the maximum temperature
with an error less than 3°C ± 3% of the reading over
the full range. Note that the error becomes larger be-

Additional Equipment Needed

• Computer Interface such as a PASCO CI inter­face or a PASPORT USB interface with an Ana­log Adapter (PS-2158).

Optional Equipment

• The sensor box accepts any Type-K thermo­couple, such as the CI-6536 High Temperature
Type-K Thermocouple Probe. The High Tem­perature Type-K Thermocouple Probe is housed
in a 30.5 cm (12”) inconel metal cover (maxi­mum temperature = +1148°C). Therefore, it can
be used in an open flame or for other high tem­perature measurements.

Type K Temperature Sensor 012-05563D

Operation

Connecting and Using the Sensor

Attach the probe’s two prong connector to the sensor
box at the port marked TYPE K THERMOCOUPLE
PROBE INPUT. The two prong connector can go into
the port only one way because one of the prongs is
wider than the other. Connect the 8-pin DIN plug
from the sensor box to Analog Channel A, B, or C on
the computer interface box.

Touch the bare wire end of the sensor to the object to
be measured or place the sensor end into the solution
to be measured. To prevent damage to the sensor or
the insulating material,
the sensor in a flame or put the insulation in contact
with a heat source above +482°C.

➤ NOTE: IF YOU NEED TO MEASURE A
TEMPERATURE HIGHER THAN +400 °C,
USE THE CI-6536 HIGH TEMPERATURE
TYPE-K THERMOCOUPLE PROBE. (See the
PASCO catalog for more information.)

do not put the insulated part of

put voltage can be converted directly into a tempera­ture. For example, an output voltage of 1.234 Volts
equals a temperature of 123.4 °C.

However, you can calibrate the sensor using a two­point calibration process.

To calibrate the sensor you will need an accurate ther­mometer, ice water (0 °C), and boiling water (100 °C).

Calibrating the Sensor Using DataStudio

Assume for this example that the Type-K Thermo­couple Temperature Sensor is connected to Analog
Channel A of the interface and that you do not have
any other sensors connected to the interface.

Start the DataStudio program. Select “Setup” from the
DataStudio toolbar. The interface and sensor should
appear in the setup window.

Select “Calibrate Sensors…” from the Experiment
Setup toolbar. Be sure that “2 point (Adjust Slope and
Offset)” is selected under “Calibration Type”.

Using the Sensor in Mild Chemical Solutions

The Type-K Thermocouple is designed to be used in
water and mild chemical solutions when measuring
the temperature of a liquid. The bare wire end of the
thermocouple has been tested for several minutes in
the following chemicals without damage:

acetone sodium hydroxide (lye)
household bleach ethylene glycol butyl ether
isopropyl alcohol ethylene glycol (antifreeze)
naphtha sulfuric acid (battery acid)
vinegar glacial acetic acid
paradichlorobenzene water

• Carefully rinse off any chemicals after each use.

Using the optional Teflon Sensor Cover

A package of ten Teflon Sensor Covers is available
from PASCO (part number CI-6549). See the PASCO
catalog for more information.

Use the optional Teflon FEP sensor cover when the
thermocouple probe must be placed in strong chemi­cal solutions that may damage the probe.

Calibrating the Sensor

The sensor is designed to produce 0.003 V ± 0.005 V
at 0 °C and 10 milliVolts per degree C. Therefore, the
sensor does not need to be calibrated. Instead, the out-

Calibration Point #1: Place the bare wire end of the
thermocouple in the ice water. Also put the thermom­eter in the ice water. The monitor screen will show the
voltage value produced by the sensor. When the ther­mometer reading is almost zero, enter the reading in
the “Standard Value” box for Calibration Point 1, then
click the “Read From Sensor” button for Calibration
Point 1.

Calibration Point #2: Place the sensor and thermom­eter in boiling water. The monitor screen will show the
new voltage produced by the sensor. When the ther-

2

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