Badger Meter PVC Tee - 1 1/2 to 4"" - Manual (Page 7)

Installation & Operation Manual
CALIBRATION
Badger Meter Impeller sensors use unique K and offset numbers for calibration. These numbers are derived from calibration
runs using NIST traceable instruments. Using both a K and an Offset number provides higher accuracy than using a K factor
alone. The K and Offset numbers for each tee configuration are listed in the "Calibration Table" below.
Calibration Table Columns
The table below provides calibration and operation data for Badger Meter Plastic Tee Sensors 1-1/2" to 4".
Column 1 Sensor Model Number
Columns 2 and 3 The K value and Offset values to use in our frequency equation:
Freq= Gpm
K
- offset
This equation describes the frequency of the output signal of all Badger Meter flow sensors. By
substituting the appropriate K and Offset values from the table, the sensor’s output frequency can be
calculated for each pipe size. This information is required when calibrating an output board or when
using the raw sensor data as direct output to interface with a device that is not a Badger Meter product.
Column 4 This column indicates the suggested flow range of each tee sensor. Badger Meter sensors will operate
both above and below the indicated flow rates. However, good design practice dictates the use of this
range for best performance.
Sensors should be sized for flow rather than pipe size. To prevent disturbances to the flow profile
always connect the sensor tee to pipe nipples measuring at least 10 pipe diameters in length on the up
stream (supply) side and at least 5 pipe diameters in length on the downstream (delivery) side before
making the transition in pipe size. If a lesser flow rate is chosen, an insufficient span exists for the proper
operation of these circuits. This can result in excessive ripple and fluctuations in signal, which can
adversely affect system performance.
Calibration Table
Model for K Offset Suggested Operating
Range (gpm)
228PV15xx-xxxx
228PV20xx-xxxx
228PV30xx-xxxx
228PV40xx-xxxx
1.697
2.8429
8.309
13.74283
-0.316
0.1435
0.227
0.23707
5…100
10…200
20…300
40…500
Page 7 January 2013