ENCARDIO RITE EDI-53P/L/I, Руководство пользователя

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Addendum to User’s Manual EDI-53 Series Digital Indicator
Page | 1
Addendum
Model EDI-53UTM Digital Indicator for Encardio-rite Model EAN-70M Uniaxial
Portable Tilt Meter
1 INTRODUCTION
The EDI-53UTM Indicator is a customized version of EDI-53 series indicator that is suitable for use
with Encardio-rite Model EAN-70M type tilt meter.
Except for the differences described below, the EDI-53 Series Digital Indicator User’s Manual [ER
document No. WI-6002.67] is valid for most of the other operations and technical specifications of this
indicator. The section numbers given below refer to the original section numbers of the User’s Manual
that are affected by the change.
2 TRANSDUCERS
2.1 The EAN-70M Portable Tilt Meter
The EDI-53UTM Indicator is meant for use with Encardio-rite Model EAN-70M type tilt meters only.
The EAN-70M tilt meter has a measurement range of
±
15
°
from vertical. It provides a full-scale output
of
±
4.14V (nominal) at
±
15
°
. The output voltage is proportional to the sine of the measured tilt angle
rather than the tilt angle in arc degrees. EAN-70M tilt meter requires an excitation supply of
±
9 to 12
V, which is supplied by the indicator.
2.2 Measurement of transducer output
The EDI-53 series indicator can measure full-scale input voltages only up to
±
2.0 V. So the EAN-70M
output voltage is internally attenuated by a factor of 2 to yield a full-scale value of
±
2 V. In the Volts
mode the full-scale tilt output from the EAN-70M would be shown as 2.0000 V by the indicator.
2.3 Calculation of parameters value in engineering units
As explained in section 3.2 above, the indicator in volts mode will show the EAN-70M output at 15
degrees as 2 V. However the value of Sin(15
°
) is 0.2588. As the EAN-70M output is linear with sine of
the measured angle, it makes more sense to display the tilt meter output in terms of sin(A) where A is
the angle of tilt.
For the indicator EDI-53UTM to show the tilt value in terms of sine of angle, at least one of the
channels of the indicator should be configured with a fixed gage factor 0.125 and offset value 0 as
described in section 5 below. The tilt meter output will now appear on the indicator display as Sin(A).
If the value of tilt angle A is required in arc degrees, the indicator reading ‘x’ can be converted to arc
degrees as follows:
A = sin
-
1(x)
As the EDI-53UTM allows the logged readings to be stored in memory and later down loaded to a
computer, a large number of indicator readings can be easily and quickly converted to corresponding
‘arc degree’ values using any commercially available spreadsheets program like Microsoft Excel.
2.4 Non-linearity correction using polynomial calculation
Polynomial correction is not required for EAN-70M tilt meter output, and hence the correction
coefficients are not provided in the supplied calibration certificates (test report) supplied with individual
tilt meters.