3.3 Relay and Open Collector Outputs
The Relay and Open Collector outputs can be used as a switch that responds when the process value moves above or below a setpoint, or they can be used to generate a pulsing signal with a rate proportional to the process value.
•Low setpoint:
Output triggers when process is less than the setpoint.
The output will relax when the process moves above the setpoint plus the hysteresis value.
•High setpoint:
Output triggers when process is greater than the setpoint.
The output will relax when the process moves below the setpoint plus the hysteresis value.
•Proportional Pulsing
The output will generate a 100 mS pulse at the rate defined by settings in the CALIBRATE menu.
In the example below:
•The output will be 0 pulses/min. when value is less than 5 ∝S.
•The output will be 50 pulses/min. when value is 7.5 ∝S.
•The output will be 100 when value is greater than 10 ∝S.
The starting point, endpoint and maximum pulse rate are selectable in the CALIBRATE menu.
Process
Hysteresis
Low Setpoint
Time
Relay energized
Relay relaxed
Process
High Setpoint
Hysteresis
Time
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| Output | Rate: |
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| . | |
| Collector Pulses/min | |||
Open |
| to | 100 |
|
0 |
|
| ||
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|
|
| |
0 pulses
5
Starting point
100 pulses
Pulse rate
10
endpoint
VIEW menu
•During normal operation, the transmitter displays the VIEW menu.
•When editing the CALIBRATE or OPTIONS menus, the transmitter will return to the VIEW menu if no activity occurs for 10 minutes.
•To select a VIEW display, press the UP or DOWN arrow keys. The selections will scroll in a continuous loop.
•Changing the VIEW display does not interrupt system operations.
•No key code is necessary to change display selection.
•Output settings cannot be edited from the VIEW menu.
Conductivity/Resistivity
62.50uS/cm
25.0°C
ENTER
CDTX-90 Series View Menu
Display
Description
123.45∝S/cm
+67.89 ºC
Monitor the Conductivity and Temperature values from the sensor. This is the permanent display.
The VIEW displays below are temporary. The permanent display will return after 10 minutes
Loop Output: | Monitor the Loop Current output. | |
13.75 mA | ||
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Last CAL: | Check the Last Calibration date. | |
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