PRODUCTS

Intended Use & Applications

Primary Function:

• Metrological standard for transferring the International Temperature Scale (ITS-90)

• Reference standard for thermometer verification and calibration

Specific Applications:

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Technical Specifications

Important: The above table contains placeholders [ ] because the original product webpage did not list numerical values. Please consult Xi’an Yunyi directly or refer to the product datasheet for the exact specifications of the WZPB-2 model.

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Construction & Design Features

1. Platinum Sensing Element

• High-purity platinum wire wound in a strain-free configuration

• Provides excellent stability and reproducibility

• Meets the purity requirements of ITS-90

2. Quartz Sheath

• High-purity quartz (silica) material

• Excellent electrical insulation properties at high temperatures

• Chemically inert and resistant to thermal shock

• Allows clear visual inspection of the internal element

3. Four-Wire Connection

• Eliminates lead resistance errors

• Enables high-accuracy resistance measurement

• Standard configuration for precision thermometry

4. Construction Quality

• Robust mechanical design for laboratory use

• Suitable for immersion in various calibration baths (water, oil, salt, or sand)

• Designed for long-term stability under proper use conditions

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Applicable Standards & Regulations

This SPRT complies with the relevant national and international standards for standard platinum resistance thermometers, including:

• ITS-90 – International Temperature Scale of 1990

• IEC 60751 – Industrial platinum resistance thermometers and sensors (reference for characteristics)

• JJG 160 – Chinese national verification regulation for standard platinum resistance thermometers

The thermometer is suitable for use as a Grade II standard in secondary calibration laboratories.

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Included in Standard Delivery

• WZPB-2 Standard Platinum Resistance Thermometer (quartz sheath)

• Factory calibration certificate (typically with fixed-point calibration data)

• Protective storage case

• Instruction manual (Chinese / English available upon request)

Optional accessories (sold separately):

• Calibration certificate with accredited traceability (third-party)

• Extension leads or connectors

• Annealing furnace for periodic maintenance (if required)

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Operation & Care Guidelines

Before Use:

1. Inspect the quartz sheath for cracks, chips, or contamination.

2. Check insulation resistance if a megger is available (should be >100 MΩ at room temperature).

3. Ensure proper immersion depth – typically at least 15-20 times the sheath diameter to minimize stem conduction errors.

4. Connect correctly using 4-wire configuration to avoid lead resistance errors.

During Use:

• Handle with care – quartz is fragile and can break if dropped or struck.

• Avoid thermal shock – do not move the thermometer directly from a hot furnace to a cold bath. Allow gradual temperature changes.

• Use appropriate protection tubes if the environment is chemically aggressive or physically harsh.

• Do not exceed the maximum rated temperature – excessive heat can permanently shift the resistance characteristics.

• Use the specified measurement current (typically 1 mA) to minimize self-heating errors.

After Use:

• Clean the sheath with a soft, lint-free cloth. For stubborn residues, use a mild solvent suitable for quartz.

• Store in the protective case in a clean, dry, vibration-free environment.

• Avoid contact with hard surfaces – even minor scratches can affect performance.

Periodic Maintenance:

• Annual verification against fixed-point cells (zinc, tin, water triple point) to confirm stability.

• Annealing may be required after exposure to high temperatures – consult the manual.

• Recalibration by an accredited laboratory every 1-2 years depending on usage frequency.