ISR 12-LO • IGAR 12-LO Operating Manual Troubleshooting • 41
9 Troubleshooting
Before sending the pyrometer for repair, try to find the error and to solve the problem with the
help of the following list.
Temperature indication too low
• Incorrect alignment of the pyrometer to the object.
⇒ New correct alignment to achieve the max. temperature signal (see 3.6).
• Incorrect focusing of the optics.
⇒ Focus correctly to the measuring distance if necessary change lens (see 3.5).
• Emissivity slope set too high.
⇒ Set lower correct emissivity slope corresponding to the material (see 4.6).
Temperature indication too high
• Emissivity slope set too low.
⇒ Set lower correct emissivity slope corresponding to the material (see 4.6).
• The measurement is influenced by reflections of hot machine parts.
⇒ Use mechanical construction to avoid the influence of the interfering radiation
(sighting tube).
Measuring errors
• Indicated temperature is immediately 1 °C below beginning of temperature range.
Contamination of the lens or broken fiber.
⇒ Clean lens or control the fiber. Recommendation: use of air purge (see 2.6).
• Indicated temperature is immediately 1 °C below beginning of temperature range, although
the air purge unit is used. Probably compressed air is not clean or air failed.
⇒ Clean the lens and use clean, dry and oil free compressed air.
• HF-interferences.
⇒ Correct the connection of the cable shield (see 4).