Please also refer to the documentation included with the measuring instrument. The thermal anemometer probe is designed to measure and inspect laboratory fume cupboards in conjunction with the Testo 400 measuring instrument.

1 Connect the probe to the measuring instrument.
2 Push down the probe protection cap until it can go no further, both openings must be uncovered.
3 Pull out the probe to the required length.

Align the probe head such that the flow direction corresponds to the arrow on the probe head. In the case of deviations from the exact alignment, the probe shows the correct reading even if the angle is turned by 20°.
Push up the probe protection cap as far as it will go so that the measurement sensor is protected.

TESTO 0635 1047 Thermal anemometer probe specifications:

• Application temperature: 0 to +50 °C/32 to 122 °F
• Sensor: Thermal
• Measurement range :0 to 5.00 m/s
• Accuracy(at 22 °C): ± (0.02 m/s + 5 % of reading)
• Time constant :< 0.5 s
• Adjustment: In free jet Ø 350 mm, reference pressure 1013 hPa, referred to testo reference DKD laboratory velocity.
• Absolute pressure: Compensation in testo 400, testo 454
• Standard: Corresponds to EN 14175-3, -4 (Draft)