Chapter 3 – Taking Measurements
Taking Measurements
26
Brüel & Kjær
Type 2239 B
Hand-Arm Vibration Functions User Manual
9.
If you want to download your results to a computer, then
refer to section 4.3.
3.3.3
Overload Conditions
If you measure vibration with peak values higher than the
upper limit of the measurement range, then the vibration me-
ter will register an overload. This may invalidate your meas-
urement because the instrument is not capable of reading how
fast the acceleration was, only that an overload occurred.
Overloads are indicated in two ways:
1.
Instantaneous Overload
: If an overload has occurred within
the last second, then the upper limit of the measurement
range value will change to read “
OVL
”, as shown in Fig. 3.3,
until the overload stops.
2.
Latched Overload
: If the instrument is taking a measure-
ment when the overload occurs, it will show
OVL
until the
overload stops (as described above). Thereafter, the up-
per limit of the measurement range will blink until a new
measurement is started.
If an overload has occurred, then stop measuring (if neces-
sary), increase the measurement range by pressing
and
retake the measurement.
Overloads are also indicated in printouts and in records.
●
In recalled records, all parameter values will blink if an
overload occurred in that record (see section 4.1.3)
Fig.3.3 Instantaneous overload
RUN
00:05:41
Amp
17.9 m/ss
H Aeq
7.26 m/ss
.1
OVL
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