GESTRA NRR 2-50, Оригинальное руководство по установке и эксплуатации

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26 NRR 2-50, NRR 2-51 - USA - Installation & Operating Manual -
850699-00
Operating the level controller
Setting the measuring range (on the NRGT 26-2)
Attention
If the NRGT 26-2 level transmitter is connected, please set the upper and lower
bounds of the measuring range only on the transmitter.
Parameter Control deviation Control valve
Proportional
band
Pb
Larger Large remaining deviation Reacts slowly
Smaller Small remaining deviation
Reacts quickly and may open/close
continually
Example
Measuring range 100% = 7.87 in (200 mm) from sight glass
Set point SP = 80% of measuring range = 6.3 in (160 mm)
Proportional band Pb = +/- 20% of set point = +/- 16% = +/- 1.26 in (32 mm)
If the measuring range is 100% [7.87 in (200 mm)] and the set point is 80%
(160 mm), the proportional band will be +/- 16% [+/- 1.26 in
(32 mm)] or in the range from 5.04 in (128 mm) to 7.56 in (192 mm).
Integral
action
time
ti
Larger Slow correction of deviations Reacts slowly
Smaller Fast correction of deviations,
control loop may tend to overshoot
Reacts quickly
Guide to setting control parameters
A
Lower bound of measuring range, adjustable
B
Upper bound of measuring range, adjustable
C
Measuring range [mm] = xxx%
D
Inactive ranges
E
Maximum electrode length at 460 °F (238 °C)
Set the lower and upper bounds of the measuring
range for your fill level measurement. The result is
measuring range C .
Please convert the measuring range into percent.
NRGT 26-2
A
D
D
1.5 in
(37 mm)
1.05 in
(26 mm)
B
C
E