Installation guide
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Cooper Bussmann BU-905U-L Wireless I/O Configuration Manual
Setting Setpoints
Setpoints let you generate a discrete setpoint status signal based on the value of an analog input.
Each setpoint status is associated with two setpoint values - a high threshold value and a low threshold value.
When the analog level moves above the high setpoint value, the setpoint status turns off. When the analog level moves below the low setpoint
value, the setpoint status turns on. If the analog input remains between the threshold values, the setpoint retains its previous value
(i.e., does not change state). This provides a measure of hysteresis.
NOTE: The high setpoint MUST be higher (i.e., greater value) than the low setpoint.
The analog input and the thermocouple input setpoints allow selection between ten different threshold pairs using the rotary switch on
the front panel.
For more information on translating analog signal types, see Appendix A – Tables for translating different analog signal types on page 75.
BU-Config lets you set the following setpoints:
Feature Description Example
Analog Setpoint This setpoint is associated with the 4-20mA analog input.
One of ten different pairs of (low setpoint, high setpoint) is selected by the
position of the rotary switch on the front panel of the BU-905U-L-T module.
Alternatively the analogue setpoint threshold values can be set to single values
(select the Single tab) independent of the rotary switch position.
“NO” indicates the switch position for this setpoint setting.
Low SP and High SP are the low and high threshold values.
Units: By changing the Units setting, the values of high and low thresholds
can be displayed in different format.
• Raw - data format used by Cooper Bussmann modules for transferring
analog values. 16384 corresponds to 4mA, or 0% reading, and 49152
corresponds to 20mA or 100% reading
• mA –actual milliamp value for a 4-20mA input.
• % - percentage of full scale. 4mA is 0%; 20mA is 100%.
For more information on the relationship between different analog units in
the BU-905U-L-T, see Appendix A – Tables for translating different analog
signal types on page 75.
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