9.3.7. Maximum Peak Value (PEAK↑)
Maximum peak value with the display abbreviation “PEAK↑”is the highest absolute magnitude
(negative or positive) of the instantaneous vibration signal (human vibration, acceleration,
velocity or displacement) since the start of measurement. A new measurement is started by the
ESC key which resets the peak memory.
If an overload occurs during the measurement of the maximum peak value, a message
OVER
LOAD
is displayed instead of the corresponding measuring value. The overload indication
remains on the display even if the measured magnitudes return to normal values since the
measured maximum value was invalid. The overload indication can be reset by pressing the
ESC key.
9.3.8. Crest Factor (CREST)
Crest factor with the display abbreviation “CREST” is the ratio of the peak value and the
running RMS value of the selected vibration quantity (human vibration, acceleration, velocity or
displacement) over a measuring period of one second.
RMS
PEAK
CREST
=
The crest factor has no measuring unit. It can be used to determine the amount of vibration
peaks in a signal. For a sine-wave signal the crest factor is 1.41.
If an overload occurs during crest factor measurement, a message
OVER LOAD
is displayed
instead of the corresponding measuring value until normal magnitudes are measured again.
9.4. Saving User-Defined Setups
After the selection of vibration quantity, filter and display mode you will be asked if you want to
save your settings (“Save settings?”). If you press the ESC key, you will then escape the setup
menu without saving. However, the changes you have made will be adopted. By pressing the
OK key you may save your settings in order to recall them later.
To save your settings, select the desired memory number (“Setup no.”) using the ▲▼ keys. Ten
memory locations (0 to 9) are available.
After pressing OK you may enter 20 characters for an individual setup name using the ◄▲▼►
keys. The preset name is the last entered setup name. Press OK to finish saving.
The menu function “6/8: Load defaults” overwrites the user-defined setups by the following
default settings:
Setup 0: “HAND_ARM_RMS_INTERV”
Hand-arm, W
h
, interval RMS
Setup 1: “HAND_ARM_AHV”
Hand-arm, W
h
, vibration total value A
hv
Setup 2: “SEAT_SURFC_RMS_INTV”
Whole-body, seat, W
d
(X/Y) + W
k
(Z), interv. RMS
Setup 3: “SEAT_SURFC_RMS_RUNG”
Whole-body, seat, W
d
(X/Y) + W
k
(Z), running RMS
Setup 4: “SEAT_SURFC_MTVV”
Whole-body, seat, W
d
(X/Y) + W
k
(Z), MTVV
Setup 5: “SEAT_BACK_RMS_INTVL”
Whole-body, backrest, W
d
(X/Y) + W
c
(Z), interv. RMS
Setup 6: “SEAT_ BACK _RMS_
RUNNG” Whole-body, backrest, W
d
(X/Y) + W
c
(Z), running RMS
Setup 7: “SEAT_ BACK _MTVV”
Whole-body, backrest, W
d
(X/Y) + W
c
(Z), MTVV
Setup 8: “ACC_WHOLEBODY_CREST”
Acceleration, 0.4 – 100 Hz, crest factor
Setup 9: “ACC_WIDEBAND_RMS”
Acceleration, 0.4 – 10 000 Hz, running RMS
Please note that the entered multiplying factors k
x
, k
y
and k
z
of vibration total value A
hv
(see section
9.3.5) are not saved with the user-defined setups.
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