Doc# 0296-0018 • REV R (July 2017) Page 56 of 61
29.3 Hz D x 0.01 = v
(0.05 inches pk-to-pk = 5 ips)
44.3 Hz D x 0.01 = A
(0.05 inches pk-to-pk = 5 g’s)
61.44 Hz V = g
(1 ips = 1 g)
Standard Checks for Transducers
There are two standard checks that can be very easily made with the TTS:
• Linearity Check
• Frequency Response Check
Linearity - The closeness of a calibraon curve to a specied straight line, preferably passing through
zero. Commonly specied as a % of full scale.
Frequency Response - The poron of the frequency spectrum over which a device can be used, within
specied limits of amplitude error.
Linearity Check - is a check to determine that the output sensivity (mV/Unit of vibraon, i.e., mV/g),
or actual reading, is maintained from a minimum operaon level to a higher operang level while not
changing the test frequency. This check is usually made at 100 Hz. The transducer manufacturer usually
species this frequency on the transducers original calibraon cercate. If in doubt, use 100 Hz.
Frequency Response Check - is a check to determine that the output sensivity (mV/Unit of vibraon),
or actual reading, is maintained over a normal operang frequency range. The reference input vibraon
level is held at a constant level for the frequency response test.
Below are some typical Transducer Checkout sample data sheets that outline typical test frequencies
and vibraon levels for checking accelerometers and velocity transducers. These parameters should
meet most general purpose requirements for verifying the funconality of transducers and measuring
systems.
Step 1. Follow the operang procedure in Monitor Mode or Sensivity Mode except substute the
frequencies and levels provided in the sample data sheets.
Step 2. Turn the down the Amplitude control knob before switching the Frequency Range to avoid jolt-
ing the shaker if operang in the Monitor Mode.
Accelerometer
Reference Level 0.25 g 0.5 g 1.0 g 2.0 g 3.0 g
Test Number A B C D E
Actual Level
Frequency (Hz) 100 200 500 1 k 2 k 4 k
Test Number A B C D E F
Actual Level
TABLE 5-6: LINEARITY CHECK - FREQUENCY 100 HZ
TABLE 5-7: FREQUENCY RESPONSE CHECK - REF. LEVEL 1 G
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