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7.3 Configuring, ranging, and simulating outputs
7.3.1 Purpose
This section describes how to configure, range, and simulate the two analog current
outputs.
Important
Configure the outputs first.
1. Configuring an output means
a. Assigning a sensor and measurement (chlorine or temperature) to an output.
b. Selecting a 4-20 mA or 0-20 mA output.
c. Choosing a linear or logarithmic output.
d. Turning output current dampening on or off.
e. Selecting the value the output current goes to if the transmitter detects a fault.
2. Ranging the output means assigning values to the low (0 or 4 mA) and high (20 mA)
outputs.
3. Simulating an output means making the transmitter generate an output equal to
the value you enter.
7.3.2 Definitions
Analog current
output The transmitter provides either a continuous 4-20 mA or 0-20 mA
output signal proportional to chlorine or temperature.
Assigning an
output Outputs can be assigned to either the measurement (total chlorine) or
temperature. If a dual input transmitter is being used, the outputs are
freely assignable to either sensor.
Linear output Linear output means the current is directly proportional to the value of
the variable assigned to the output (chlorine or temperature).
Logarithmic
output Logarithmic output means the current is directly proportional to the
common logarithm of the variable assigned to the output (chlorine or
temperature).
Dampening Output dampening smoothes out noisy readings. It also increases
response time. The time selected for output dampening is the time to
reach 63% of the final reading following a step change. Output
dampening does not affect the response time of the display.
Fault The transmitter continuously monitors itself and the sensor(s) for
faults. If the transmitter detects a fault, a fault message appears in the
main display. At the same time, the output current goes to the value
programmed in this section. There are two output fault modes:
fixed
and
live
.
Fixed
means the selected output goes to the previously
programmed value (between 0.00 and 22.00 mA) when a fault occurs.
Live
means the selected output is unaffected when the fault occurs.
Programming the transmitter
Instruction Manual 41