Black Box ServSensor JR EME102A, Manual, Page: 44 / 135

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ServSensor JR
42
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ServSensor JR autodetects the presence of the 4-20mA
Converter
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Up to 2 4-20mA Converters on the ServSensor JR
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Full autosense including disconnect alarm
Configuring the 4-20mA Converter
Since all of BLACK BOX's intelligent sensors are configured similarly
not every field is described below. The descriptions below describe the
fields that are special to the 4-20mA Converter.
For a general description about configuring all sensors including
information regarding common configuration parameters please see the
Installing and Configuring Sensors page.
Current Reading: The percentage of current is displayed in this field.
This is a read-only field. This is an integer SNMP OID field. This
value can be polled via SNMP and the data can be used to graph the
airflow. 4-20mA current is mapped to 0 to 100 %.
A/D base in 1/10 volt increments: This is the minimum voltage that
the 4-20mA Converter will output. This value in conjunction with the
maximum voltage from the sensor is used to determine the percentage
of the sensor. For the 4-20mA Converter this value is automatically set
to 8. In other words, when the Converter has 4mA as an input, the
output to the A/D converter in the ServSensor JR will be 8 volts
A/D max, Range 0-50, 50 is 5 volts: This is the maximum voltage that
the DC Voltage sensor will output. This value in conjunction with the
minimum voltage from the sensor is used to determine the percentage
of the sensor. For the 4-20mA Converter the A/D max is set to 40. In
other words, when the Converter has 20mA as an input, the output to
the A/D converter in the ServSensor JR will be 4 volts.
Status: The status is formed by comparing the percentage of full scale
to the high and low thresholds. The percentage of the current to full
scale is then compared to the thresholds of Low Warning, High