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

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Addendum to User’s Manual EDI-53 Series Digital Indicator
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3 TAKING MEASUREMENTS
The EDI-53P-C is intended for use with three terminal passive potentiometric transducers. The
standard EDI-53P indicator signal leads consist of four leads out of which only three are used. The
fourth lead is not used for measurement and is also not internally connected inside the indicator.
The method of connecting the signal leads of the indicator is illustrated in the figure below.
EDI-53P-C
7
Pi
n
c
on
nect
or
Red lead with red clip
Red lead with yellow clip
Black lead with yellow clip
Black lead with black clip
Potentiometric
sensor
No connection
O/P
+Ve
- Ve
(ref.)
V
IN
OUT
V
As the input signal cable is a standard EDI-53 indicator cable it can be used with any other version of
EDI-53 as a replacement.
Special precaution: Three wire potentiometric transducer output is subject to measurement errors due
to conductor resistance of long signal leads. Use the shortest possible length of cable between the
transducer and the indicator. If that is not possible always use the same cable for taking the
measurements. A five wire measurement technique is required to eliminate this error.
4 PREPARING SETUP DATA
1. Units – Choose the appropriate symbol if available in the indicator (i.e. select key ‘4’ when
prompted for the units value to use ‘mm’) else select blank (key 9).
2. Initial Reading or Coefficient C – Enter the zero offset value if given in the calibration
certificate or the initial value after installation as required by the application. To use the initial
setting as zero reference, after installation of the potentiometric transducer, measure its initial
value in ‘VOLTS’ mode. This value should be entered as Initial Reading and will serve as the
zero-reference value for all subsequent measurements, i.e., this zero value is subtracted from
all subsequently measured values to get the actual change in parameter value.
3. Gauge Factor or Coefficient B – Enter the calculated value of gauge factor ‘G’ as explained
above.
4. Coefficient A – This value should be left at 0.0000E+00 as polynomial calculation
coefficients are not generally provided for potentiometric transducers by the manufacturers.
However, if available the coefficient of x
2
can be entered for better accuracy.
Figure 3-1