Metrix HI 803 User Manual

Doc# 0296-0018 • REV R (July 2017) Page 55 of 61
Sensivity Mode Phase Check
During the sensivity tesng of an accelerometer, the phase relaon- ship can be compared to the
internal reference accelerometer.
The HI-803 automacally does a phase check when the test frequency is set below 60 Hz. A small arrow
appears in the lower right corner of the display. The arrow points up when the TUT is in phase with the
internal reference and points down when the TUT is out of phase with the internal reference.
The Phase Check should be the starng point when troubleshoong the TTS for errac readings, read-
ings that don’t sele down when the shaker is running.
Step 1. With the shaker running turn the Frequency Knob counter- clockwise unl the reading is
below 60 Hz.
Step 2. Check to see the posion of the arrow in the lower right hand corner of the display.
Step 3. If the arrow is poinng up the phase is correct.
Step 4. If the arrow is poinng down the phase is incorrect.
Operang Hints
The informaon contained in this secon is for reference only and is provided as useful informaon
when operang the HI-803 TTS.
General Vibraon Informaon
Relaonship in the Characteriscs of Vibraon Signals for Sine Waves
There is a specic relaonship in the characteriscs of vibraon signals that hold true for sine waves.
rms value = 0.707 x peak value
rms value = 1.11 x average value
peak value = 1.414 x rms value
peak value = 1.57 x average value
verage value = 0.637 x peak value
peak-to-peak = 2.0 x peak value
Relaonships of Sinusoidal Velocity, Acceleraon and Displacement
English Units:
V = 3.14 fD D = meters pk-to-pk
V = 61.44 g/f V = meters per second
g = 0.0511 f2 D f = Hertz
g = 0.0162 Vf g = 386.1 in/sec2 D = 0.3183 V/F
D = 19.57 g/f2
Metric Units:
V = 3.14 fD D = meters pk-to-pk
V = 1.56 g/f V = meters per second
g = 2.013 f2 D f = Hertz
g = 0.641 Vf g = 9.80665 m/sec2 D = 0.3183 V/F
D = 0.4968 g/f2
Crossover Frequencies for the TTS
At the crossover frequencies indicated in the samples below, like num- bers are displayed by the TTS.
This characterisc makes these frequencies a good choice to make quick operaonal reference checks.

Metrix HI 803 Specifications

General

Brand	Metrix
Model	HI 803
Category	Test Equipment
Language	English