RLE Wi-MGR V.1.6 - Manual (Page 34)

34 Wi-MGR User Guide 800.518.1519
3 Web Interface
Gain
(Wi-ASx/Wi-MS)
and
Offset
(Wi-ASx/Wi-MS)
Applies only to analog 4-20mA, 0-5V, and 0-10V input types. Inputs
like temperature, humidity, pressure, etc. convert information to an
analog signal. The Wi-MGR reads this raw analog signal and
calculates a value based on the input and the predetermined gain
and offset settings.
The idea is to determine the correct gain and offset values so that
the Wi-MGR calculates and displays accurate readings. Without
setting the correct gain and offset, the Wi-MGR will not convert the
raw data correctly. As a result, missed alarms or nusiance alarms
occur. Gain and offset values for sensors are as follows:
Wi-AS1 (Analog 0-20mA)
Gain = (sensor high range value - sensor low range value) ÷ 3277
Offset = sensor low range - ( (sensor high range value - sensor low
range value) ÷ 4)
Example: Temperature sensor with a sensing range of 50-95°F -
displayed in Fahrenheit
Gain = (95 - 50) ÷ 3277 = 0.013732
Offset = 50 - ( (95-50) ÷ 4) = 50 - 11.25 = 38.75 (round up to 39)
Example: Humidity sensor with a range of 0-100% RH
Gain = (100 - 0) ÷ 3277 = 0.0305157
Offset = 0 - ( (100 - 0) ÷ 4) = -25
Wi-AS2 (Analog 0-5mA) and Wi-AS3 (Analog 0-10mA)
Gain = (sensor high range value - sensor low range value) ÷ 4096
Offset = sensor low range - ( (sensor high range value - sensor low
range value) ÷ 4)
Example: Temperature sensor with a sensing range of 50-95°F -
displayed in Fahrenheit
Gain = (95 - 50) ÷ 4096 = 0.0109863
Offset = 50 - ( (95-50) ÷ 4) = 50 - 11.25 = 38.75 (round up to 39)
Example: Humidity sensor with a range of 0-100% RH
Gain = (100 - 0) ÷ 4096 = 0.024414
Offset = 0 - ( (100 - 0) ÷ 4) = -25
BAPI 4-20mA, BAPI 0-5mA, and BAPI 0-10mA Transducers
Gain = (sensor high range value - sensor low range value) ÷ 4096
Offset = sensor low range value
Example: Temperature sensor with a sensing range of 50-95°F -
displayed in Fahrenheit
Gain = (95 - 50) ÷ 4096 = 0.0109863
Offset = 50
Option Description