RS PRO RS-41 Digital Thermometer

Introduction

This instrument is a portable 3½ digit, compact-sized digital thermometer designed to use an external K-type thermocouple as a temperature sensor. Temperature indication follows National Bureau of Standards and IEC584 temperature/voltage tables for K-type thermocouples. One K-type thermocouple is supplied with the thermometer.

Safety Information

It is recommended that you read the safety and operation instructions before using the thermometer.

⚠️ WARNING: TO AVOID ELECTRICAL SHOCK. DO NOT USE THIS INSTRUMENT WHEN VOLTAGES AT THE MEASUREMENT SURFACE EXCEED 24V AC OR 60V DC.

⚠️ WARNING: TO AVOID DAMAGE OR BURNS. DO NOT MAKE TEMPERATURE MEASUREMENTS 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. The ⚠️ symbol on the instrument indicates that the operator must refer to "Input protection" in this manual.

Specifications

Electrical

Temperature Scale

Celsius (℃), Fahrenheit (℉) or Kelvin (K) user-selectable

Measurement Range

-50 ℃ to 1300 ℃, -58 ℉ to 2000 ℉, 223K to 2000K

Resolution

1 ℃ or 1 ℉, 0.1 ℃ or 0.1 ℉, 1 K

Accuracy

Accuracy is specified for operating temperatures over the range of 18 ℃ to 28 ℃ (64 ℉ to 82 ℉), for 1 year, not including thermocouple error.

• +2 ℃: -50 ℃ to 0 ℃
• +4 ℉: -58 ℉ to 32 ℉
• +5K: 223K to 273K
• ±(0.5% rdg+1℃): 0 ℃ to 1000 ℃
• ±(0.8% rdg+1℃): 1000 ℃ to 1300 ℃
• ±(0.5% rdg+2 ℉): 32 ℉ to 2000 ℉
• ±(1.0% rdg+2K): 273K to 2000K

Temperature Coefficient

0.1 times the applicable accuracy specification per ℃ from 0 ℃ to 18 ℃ and 28 ℃ to 50 ℃ (32 ℉ to 64 ℉ and 82 ℉ to 122 ℉).

Input Protection

60V dc or 24V rms ac maximum input voltage on any combination of input pins.

Reading Rate

2.5 times per second.

Input Connector

Accepts standard miniature thermocouple connectors (flat blades spaced 7.9mm, center to center).

Environmental

Ambient Operating Range

0 ℃ to 50 ℃ (32 ℉ to 122 ℉)

Storage Temperature

-20 ℃ to 60 ℃ (-4 ℉ to 140 ℉)

Relative Humidity

0% to 80% (0 ℃ to 35 ℃) (32 ℉ to 95 ℉)

0% to 70% (35 ℃ to 50 ℃) (95 ℉ to 122 ℉)

General

Display

3 ½ digit liquid crystal display (LCD) with maximum reading of 1999

Battery

Standard 9V battery (NEDA 1604, IEC 6F22)

Dimensions

162mm (H)×76mm(W)×38.5mm(D)

Weight

210g

Supplied Probe

1 x 1.2m type "K" thermocouple bead probe (Teflon tape insulated). Maximum insulation temperature 260 ℃ (500 ℉)

Probe accuracy ±2.2 ℃ or ±0.75% of reading (Whichever is greater) from 0 ℃ to 800 ℃

Operating Instructions

Selecting the Temperature Scale

Readings are displayed in either degrees Celsius (℃), degrees Fahrenheit (℉) or degrees Kelvin (K). When the thermometer is turned on, it is set to the temperature scale that was in use when the thermometer was last turned off. To change the temperature scale, press the “℃”, “℉” or “K” key.

Selecting the Display Resolution

The thermometer allows two choices of resolution:

• High resolution: 0.1 ℃ or 0.1 ℉
• Low resolution: 1 ℃ or 1 ℉

Overload Display (1)

The digital display will indicate 1 when the input exceeds the measurement range selected. If measuring above 199.9°, change the resolution to 1°. Be certain to seat the thermocouple connector properly and that the leads are not broken.

Hold Mode

Press the "HOLD” key to enter the Data Hold mode, the “HOLD” annunciator is displayed. When HOLD mode is selected, the thermometer holds the present readings and stops all further measurements. Press the “HOLD” key again to cancel HOLD mode and to resume taking measurements.

Max Mode

Press the "MAX" key to enter the MAX mode. The thermometer then records and updates the maximum values and the MAX annunciator appears on the display. Press the "MAX" key again to exit the MAX recording mode. In the MAX mode, press the “HOLD” key to stop the recording, press “HOLD” again to resume recording.

Backlight Mode

Press the BACKLIGHT key to turn on the LCD backlighting function. The LCD backlighting will auto-off after the BACKLIGHT key is released after approximately 5 seconds.

Tc (Temperature Compensator) Checking Mode

Press and hold the “Tc” key to enter the temperature compensator-checking mode. The thermometer will display inside temperature.

Maintenance & Cleaning

1. Repairs or servicing not covered in this manual should only be performed by qualified personnel.
2. Periodically wipe the case with a dry cloth. Do not use abrasives or solvents on this instrument.

Battery Replacement

⚠️ The following safety information must be observed to ensure maximum personal safety during the operation of this instrument.

• To avoid electric shock, remove the thermocouple probes before removing the battery door.
• When replacing the instrument batteries, do not mix batteries of different types or old and new batteries.
• Check the battery polarity carefully when inserting the batteries.
• To avoid electric shock, do not operate the meter until the battery door is in place and fastened securely.
• Do not short-circuit used batteries, disassemble them, or throw them in a fire. Doing so may cause the batteries to explode.
• Dispose of the used batteries in accordance with local regulations.

The battery symbol ? appears on the lower right of the LCD when the 9V battery needs to be replaced.

Replace the 9V battery as follows:

1. Turn the meter off and disconnect the temperature probe.
2. Remove the rubber holster that surrounds the entire meter by pulling it over the top of the meter.
3. Remove the small Phillips head screw on the rear of the meter.
4. Open the battery compartment and replace the 9V battery.
5. Re-assemble the meter before operating.

Limited Warranty

This meter is warranted to the original purchaser against defects in material and workmanship for 1 year from the date of purchase. During this warranty period, RS Components will, at its option, replace or repair the defective unit, subject to verification of the defect or malfunction. This warranty does not cover fuses, disposable batteries, or damage from abuse, neglect, accident, unauthorized repair, alteration, contamination, or abnormal conditions of operation or handling. Any implied warranties arising out of the sale of this product, including but not limited to implied warranties of merchantability and fitness for a particular purpose, are limited to the above. RS Components shall not be liable for loss of use of the instrument or other incidental or consequential damages, expenses, or economic loss, or for any claim or claims for such damage, expense or economic loss. Some states or countries laws vary, so the above limitations or exclusions may not apply to you. For full terms and conditions, refer to the RS website.