Badger Meter Blancett B220-880, User Manual

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Internal Pullup Resistor
The internal pullup resistor is used for a simple installation Make sure that the device being connected to the pulse output
can accept voltage levels as high as the supply feeding the K-factor scaler Make sure the output pulse from the K-factor scaler
can supply enough current for the receiving device to read the pulse when using an internal pullup resistor Use the following
equation to calculate the available current that the K-factor scaler can supply to the receiving device See Figure 7
Available Current =
(Input Voltage - 0.7V)
(3600Ω + 47Ω)
Using the equation above, the maximum current available at an input voltage of 30V is 8 mA Verify that the receiving device
input current requirement is below this value for proper operation Use an external pullup resistor less than 3 6 kΩ if the value
is higher than the available current
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1 2 3 4 5
ON C&K SDA05
1 2 3 4 5
ON C&K SDA05
9 9 9 9 9 9 9 9
, ,
P1
P2
P4
S10
TB1
Open Collector
Pulse Output
Switch 5 On
(Up)
8 mA
Maximum
Voltage Input
Internal
3.6k Ω
Figure 7: Wiring schematic with internal pullup resistor in circuit
Startup and Configuration
Page 10 June 2021 SGN-UM-00281-EN-06