Testo 735-2 Digital Thermometer (Multichannel)

Key Features:

1. Up to 6-channel measurement capability
   Connect up to 3 wired probes and an additional 3 wireless temperature sensors for simultaneous measurement on up to six channels.
2. High-precision measurement with Pt100 option
   When used with the optional Pt100 immersion/penetration probe, the system accuracy reaches up to ±0.05 °C and resolution down to 0.001 °C—ideal for calibration and critical lab applications.
3. Wide probe compatibility (TC types K, T, J, S + Pt100)
   Accepts multiple probe types: one Pt100 input and two inputs for thermocouples (TC types K, T, J, S), giving versatile measurement range from approximately –200 °C to +1,760 °C depending on probe.
4. Large memory & PC-software data management
   Built-in memory stores up to 10,000 readings, supports up to 99 measuring sites and multiple user profiles. Included PC software and USB cable enable downloading, analysis (table & graph) and documentation of measurement series.
5. Backlit display + alarm + Delta T, min/max/mean values
   The instrument displays measured values with Delta T, minimum, maximum and average values. It features a backlit screen for low-light environments and an acoustic alarm when limit values are exceeded.
6. Rugged, waterproof design – IP 65 rated
   Built to withstand harsh environments. With an IP 65 protection rating, the device is dust tight and protected against water jets. Suitable for industrial, food, pharmaceutical and HVAC/R applications.
7. Compliance with industry standards – HACCP & EN 13485
   Certified to meet HACCP-International and EN 13485 standards, making the unit suitable for food safety, pharmaceutical, cosmetics and laboratory applications.
8. Flexible logging interval & site management
   Memory cycle selectable from 0.5 seconds up to 24 hours, enabling tailored logging routines for different measuring tasks (e.g., dynamic processes or long-term monitoring).
9. Comprehensive probe options for immersion, penetration & surfaces
   Wide selection of additional sensors available (immersion, penetration, surface, air) to address diverse measurement environments with one meter platform. 
10. Ideal for calibration, laboratories, HVAC/R, food & refrigeration monitoring
    Whether measuring core temperatures, surface temperatures, air temperatures or validating stationary probes, this multichannel thermometer is designed for precision tasks in electronics, chemicals, refrigeration, food and pharmaceutical sectors.

Key Technical Specifications:

Input channels & sensor compatibility

• 3 wired input channels: 1 for Pt100 sensors + 2 for thermocouples (TC) Type K, T, J, S. 
• Support for up to 3 additional wireless temperature sensors (radio probes) for a total of up to 6 channels (3 wired + 3 wireless). 
• Compatible probe types: Pt100 immersion/penetration, TC K (NiCr-Ni), TC T (Cu-CuNi), TC J (Fe-CuNi), TC S (Pt10Rh-Pt). 

Measuring ranges, accuracy & resolution (typical)

• Pt100 sensor input: Measuring range: –200 °C to +800 °C. Accuracy: ±0.2 °C (for –100 to +199.9 °C) + ±0.2 % of measurement value for remaining range. Resolution: 0.05 °C. 
• Thermocouple Type K: Measuring range: –200 °C to +1 370 °C. Accuracy: ±0.3 °C (for –60 to +60 °C) + ±(0.2 °C + 0.3 % of mv) for remaining range. Resolution: 0.1 °C.
• Thermocouple Type T: Measuring range: –200 °C to +400 °C. Accuracy: ±0.3 °C (for –60 to +60 °C) + ±(0.2 °C + 0.3 % of mv). Resolution: 0.1 °C. 
• Thermocouple Type J: Measuring range: –200 °C to +1 000 °C. Accuracy: ±0.3 °C (for –60 to +60 °C) + ±(0.2 °C + 0.3 % of mv). Resolution: 0.1 °C. 
• Thermocouple Type S: Measuring range: 0 °C to +1 760 °C. Accuracy: ±1 °C (for full range). Resolution: 1 °C. 
• When using the optional high-precision Pt100 immersion/penetration probe (e.g., probe 0614 0235) the system accuracy can reach ≈ 0.05 °C with resolution of 0.001 °C. 

Memory & data logging

• Internal memory: Up to 10 000 measurement values can be stored. 
• Supports up to 99 measurement sites and multiple user profiles. 
• Logging (memory cycle) selectable from 0.5 seconds up to 24 hours. 
• PC-software included with USB data cable for download, analysis (tabular/graphical) and documentation of measured data.

General / housing / environmental

• Housing dimensions: 220 × 74 × 46 mm. Weight: approx. 428 g. 
• Operating temperature: –20 °C to +50 °C. Storage temperature: –30 °C to +70 °C.
• Protection class: IP65 (dust tight and protected against water jets). 
• Housing material: ABS / TPE / Metal. 
• Power supply: AA (mignon) alkaline batteries. Typical battery life (with TC probe K/T): ~200 h.
• Standard compliance: EN 13485 and HACCP-International certified (for food/pharma industries).

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