Installation
Page 7
SGN-UM-00282-EN-05
June 2021
External Pullup Resistor
Using an external pullup resistor offers greater flexibility of controlling the output
pulse provided by the K-factor board to the receiving device Since power sources
and receiving devices differ between users, different resistor values are required
for different setups
The external pullup resistor is connected between the receiving device’s input
and external power source This power source is the maximum input voltage
(of the pulse) to the receiving device Use the equation below to determine the
resistor value
R =
Supply Voltage
Current
Where:
R
= Resistor value in hms
Supply Voltage
= External supply voltage connected to the external pullup
resistor
Current
= Input current required by the receiving device in amps
After
R
has been calculated, use the value in the following equation
P = ( Supply Voltage )
Supply Voltage
R + 47 Ω
P
represents the power capability of the output and should not exceed 0 25
Watts Exceeding this value could damage the K-factor board Raising the
R
value
decreases the available power output
