Maintenance; Cleaning; Pyrometer Calibration; Troubleshooting - KPM PROCESS SENSORS METIS M311 Operating Manual

10

Maintenance

CAUTION
pull connector on the pyrometer to prevent injury by accidentally activated laser targeting light!

10.1 Cleaning

Clean the lens with a soft cloth and a bit of ethanol.
Do NOT
▪ clean the optics with solvents that contain acid
▪ immerse the optics in water or other liquids to clean

10.2 Pyrometer Calibration

To obtain the measurement accuracy, we recommend to re-calibrate the pyrometer periodically (annually) with
the help of calibration sources and optionally adjust at Process Sensors Corporation.
▪ Fiber-optic pyrometers must always be calibrated together with the associated optics and the optical fiber
cable.
▪ A recalibration is also necessary if (for fiber optic pyrometers) the optics OQ12 is replaced by OQ25 or vice
versa and / or a new fiber optic cable should be used.

10.3 Troubleshooting

Before sending the pyrometer in for repair, check whether the fault can be identified and eliminated using the
list.
▪ Lens or protective window that is soiled with an oily film,
that weakens the signal differently in the two measurement
wavelength ranges will change the emissivity ratio and cause
measurement errors.
→ Clean the lens or protective window lens with a soft cloth and
some ethanol.
▪ Optical fiber connection broken directly on the optics (caused
e.g. by pulling the optical fiber while the
optics is fixed, a measurement is no
longer possible here) or connector
scratched (caused by laying the fiber
without protective connector cap, tem-
perature display too low) or minimum
bending radius undershot (causes a
strong weakening of the signal with cor-
responding measurement errors).
Get a new fiber optic.
▪ Emissivity slope (or emissivity with 1-
measurements) is set too high (temperature reading too low) or emissivity slope (or emissivity with 1-
color measurements) is set too low (temperature reading too high).
→ Correct the emissivity slope or emissivity according to the material.
▪ Measurement error due to HF interference, e.g. pyrometer too close to an inductor.
→ Shield incorrectly connected. Connect according to chapter 4.1.6.
▪ The measurement is influenced by reflections from hot system parts (temperature display too high).
→ Shield interference radiation, e.g. with a mechanical device such as a sight tube.
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Switch off supply voltage. Before beginning any maintenance, switch off power supply or
METIS M311 / M322 / H311 / H322 (12-pin device connector)
→
color