Fluke 50S User manual

®
PN 1278540
September 1999
© 1999 Fluke Corporation, All rights reserved. Printed in USA
All product names are trademarks of their respective companies.
50S & 50D
Thermometer
Manual de Uso
Manuale d'Uso
Bedienungs-Handbuch
Mode d'emploi
Users Manual

LIMITED WARRANTY & LIMITATION OF LIABILITY
This Fluke product will be free from defects in material and workmanship for
1 year from the date of purchase. This warranty does not cover fuses, dis-
posable batteries or damage from accident, neglect, misuse or abnormal
conditions of operation or handling. Resellers are not authorized to extend
any other warranty on Fluke’s behalf. To obtain service during the warranty
period, send your defective tester to the nearest Fluke Authorized Service
Center with a description of the problem.
THIS WARRANTY IS YOUR ONLY REMEDY. NO OTHER WARRANTIES,
SUCH AS FITNESS FOR A PARTICULAR PURPOSE, ARE EXPRESSED
OR IMPLIED. FLUKE IS NOT LIABLE FOR ANY SPECIAL, INDIRECT,
INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSSES, ARISING
FROM ANY CAUSE OR THEORY. Since some states or countries do not
allow the exclusion or limitation of an implied warranty or of incidental or
consequential damages, this limitation of liability may not apply to you.
Fluke Corporation
P.O. Box 9090
Everett WA
98206-9090
Fluke Europe B.V.
P.O. Box 1186
5602 B.D. Eindhoven
The Netherlands
10/96

1
50S & 50D
Introduction
The Fluke Models 50S and 50D Thermometers (“the
thermometer”) are microprocessor-based, digital
thermometers designed to use external J-and K-type
thermocouples (temperature probes) as temperature
sensors.
Use the thermometer only as specified in this manual.
Otherwise, the protection provided by the meter may be
impaired.
Replacement Parts and Accessories
Accessory Part Number
Battery, 9V (NEDA 1604, 6F22, or 006P) 696534
80PK-1 K-Type Bead Thermocouple 773135
Service Manual 802413
Holster 890298

50S & 50D
Users Manual
2
Contacting Fluke
To order accessories, receive assistance, or locate the
nearest Fluke distributor or Service Center, call:
1-888-993-5853 in USA & Canada
[phone] in Europe
[phone] in Japan
[phone] in Singapore
[phone] from other countries
Address correspondence to:
Fluke Corporation Fluke Europe B.V.
P.O. Box 9090 P.O. Box 1186
Everett, WA 98206-9090 5602 BD Eindhoven
USA The Netherlands
Visit us on the World Wide Web at: www.fluke.com

50S & 50D
Safety Information
3
Safety Information
WWarning
A Warning identifies conditions and actions that pose
hazards to the user. To avoid electrical shock or personal
injury, follow these guidelines:
•Before using the thermometer inspect the case. Do not
use the thermometer if it appears damaged. Look for
cracks or missing plastic. Pay particular attention to the
insulation around the connectors.
•Disconnect the thermocouple(s) from the thermometer
before opening the case.
•Replace the batteries as soon as the battery indicator
(N)appears. The possibility of false readings can lead
to personal injury.
•Do not use the thermometer if it operates abnormally.
Protection may be impaired. When in doubt, have the
thermometer serviced.
•Do not operate the thermometer around explosive gas,
vapor, or dust.
•Do not apply more than the rated voltage, as marked on
the thermometer, between the thermocouple(s), or
between any thermocouple and earth ground.

50S & 50D
Users Manual
4
WWarning (cont.)
•
Model 50D : Measurement errors may occur if voltages on
the measurement surfaces result in potentials greater
than 1 V between the two thermocouples. When potential
differences are anticipated between the thermocouples,
use electrically insulated thermocouples.
•Do not operate if any voltage is present at the
measurement surface.
•When servicing the thermometer, use only specified
replacement parts.
•Do not use the thermometer with any part of the case or
cover removed.
Caution
To avoid damaging the thermometer or the equipment
under test.
•Use the proper thermocouples, function, and range for
your thermometer.
•Do not attempt to recharge the batteries.
•To prevent explosion, do not throw batteries into a fire.
•Follow local laws or regulations when disposing
batteries.
•Match the +and −polarities of the battery with the
battery case.

50S & 50D
Components
5
Components
6
1
2
50D
50S
5
4
3
aas10f.eps
A
Display
D
Thermocouple input(s)
B
Controls
E
Battery
C
OFFSET control(s)
F
Case screws

50S & 50D
Users Manual
6
Display Elements
1
10
6
8
7
9
5 4 3 2
aas11f.eps
A
Temperature display.
F
T1; or T2 or T1-T2
(Model
50D)
readings are displayed.
B
Temperature units.
G
Maximum readings are
displayed.*
C
Stored readings are
displayed.*
H
Minimum readings are
displayed.*
D
Record mode is active.*
I
Low battery.
E
Displayed readings are
frozen.
J
Thermocouple type.
* Model 50D only.
The display shows “- - - - -“ if a thermocouple is open.

50S & 50D
Controls
7
Controls
ON / OFF Turn the thermometer on or off.
F / C Switch between Fahrenheit (oF) and Celsius (oC).
HOLD Freeze or unfreeze the displayed readings. When
pressed during power-up, changes the
thermocouple type.
RECORD* Toggle Record mode on and off. (Stores MIN/MAX
readings.)
T1* Select the T1 thermocouple input. When pressed
during power-up, T1 changes the display
resolution.
T2* Select the T2 thermocouple input. When pressed
during power-up, selects Scan mode. (The display
continuously cycles between T1, T2, and T1-T2.)
T1-T2* Select the differential temperature measurement.
VIEW* Toggle the MIN/MAX readings stored in Record
mode on and off.
OFFSET* Optimize measurement accuracy for a
thermocouple at a particular temperature.
* Model 50D only.

50S & 50D
Users Manual
8
Changing to the J-Type Thermocouple
•Press HOLD during power-up.
Changing to Low Resolution
To select the low display resolution [1.0 oC (1.0 oF)]:
1. Turn the thermometer off.
2. Press T1 +ON/OFF for 2 to 3 seconds.
The alternate resolution remains set until the
thermometer is turned off.
Adjusting the Offset
To compensate for thermocouple errors:
1. Plug the thermocouple into the input connector.
2. Place the thermocouple in a known, stable temperature
environment (such as an ice bath or a dry well
calibrator) and allow the readings to stabilize.
3. Simultaneously push and turn the OFFSET control until
the display shows the correct reading.
This adjustment affects calibration.