SKF PHL FM 10/400, User Manual

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15
7.0 Calibration
7.1 Spot check
The measurement system of the SKF Belt Frequency Meter is based upon a very stable quartz
crystal that should never wander. However, a precision mechanical resonator (tuning fork) is
included with the meter so that a calibration check at a spot frequency of 250 Hz may be per-
formed at any time.
Tap the tip of the tuning
fork on a hard surface
and then hold STEADY
in front of the optical
sensor at a distance
of 10 to 15 mm. The
meter will measure a
frequency of 250 Hz
thus demonstrating
that it is in calibration.
Results within ±1% are acceptable. There is no adjustment possible. If greater variance is experi-
enced, the meter should be returned for calibration. See section 8.2 for manufacturer’s contact
information.