gefran 2300 Manual De Uso página 32

DETAILS ON LINEAR SCALES 0...10V, 0...20mA, 4...20mA
The instrument provides two different modes to manage 0...10V, 0...20mA, 4...20mA linear signals, selectable with parameters
InTyP and InCod in phase CFG3:
a) Generic linear signal mode, "Minimum Maximum" scale type
InTyP = 4, InCod = 4,5,6
The scales are factory-calibrated. In case of need, calibration in the field is performed with procedures CAL.L3, CAL.L4. The
4...20mA scale is calibrated with a 0...20mA signal. The calibration check is not available with the CAL/RST key.
b) Signal from pressure transmitter or amplified load cell mode, "Zero-Span" type scale:
InTyP = 0, InCod = 15,16,17
Calibration is performed together with the sensor, following procedures CAL.SG, CAL.AU, CAL.80 (as for strain gauges). The
scale minimum (normally = 0) is set in CGG3 with parameter LO_LIN; Span (normally about 80% of full scale) is set during
calibration phase. Parameter HI_LIN causes the _Hi_ message on the display.
You can also run the calibration check with one of the CAL/RST" or "*" keys enabled for this procedure. The calibration check
requires that the sensor have the calibration input (2 CAL wires connected to fastons 21 and 22 on the instrument).
TRIP POINTS
Absolute trip point
Setpoint set with absolute value with respect to 0. (ex. Out1=450, Out2=350, Out3=500, Out4=600). The setting range assumes
maximum values of selected scale.
Deviation trip point
Setpoint set with reference to setpoint value
ex1. Out1 absolute, the others deviation:
Out1=400, Out2=50 (trip point at 450)
Out3=80, (trip point at 480)
Out4=100, (trip point at 300)
e2. Out1, Out3 absolute, the others deviation:
Out1=400, Out2=50 (trip point at 450) Out3=300, Out4=100 (trip point at 200)
The setting range assumes values -999/999. The set value is added algebraically to the previous absolute alarm limit value (the
limit value may exceed the scale limits).
Direct trip point
Relay energized with variable above value of set trip point for both absolute and deviation type.
Reverse trip point
Relay energized with variable below value of set trip point for both absolute and deviation type.
Symmetrical deviation trip point
Value set relative to setpoint is both added and subtracted to create a trip window. This is defined direct (inverse) symmetrical
deviation with relay energized for values outside (inside) the window.
Calibration control function
Activated by key or by specifically configured digital input. It involves:
- blocking of trip points
- closing of calibration contact (fastons 21 and 22)
- lighting of CAL LED
- display of input corresponding to value supplied by probe or transmitter for activation time of key or of digital input.
HOLD Function
The input value and the trip points remain "frozen" as long as the logic input is active. With the input active, a reset of the
setpoint memory de-energizes all energized relays and resets all alarm memories
FLASH Function
The input value is sampled and trip points are "frozen." When the logic input becomes active, the input value is "frozen" and the
trip points are updated in base to the last acquired value.
PROGRAMMING BY P.C.
All configuration and calibration procedures can be run with an IBM * Personal Computer (or compatible), with suitable manage-
ment software and interface (CL, RS485)
* IBM is a registered trademark of International Business Machines.
10 • FUNCTION NOTES
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