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An output may be controlled in one of three ways – a scaled mapping to an input, an on/off control from an input
setpoint, or as an input alarm. Sections
5.4.2
through
5.4.4
describe these output control methods.
5.4.1
Device Output Range/Types
There are three types of output options – On/Off, Pulse-Width Modulation (PWM), or Servo. This section
describes these output options.
5.4.1.1
ON/OFF Output Type
The ON/OFF output mode switches the output to be a binary ON or OFF. Depending on if the
output is configured as Active Low or Active High, the ON/OFF mode can correspond to different
polarities.
5.4.1.2
Pulse-Width Modulation (PWM) Output Type
Pulse-Width Modulation (PWM) controls the amount of power given to a device by cycling the
on/off phases of a discrete signal. PWM consists of a duty cycle and frequency. The Duty Cycle
measures the amount of time a signal is in the ON state as a percentage. The frequency controls
how fast the PWM cycle is repeated. Users can select between the following settings:
Option
Value
Description
Rate
100 Hz
Signal has a constant 100 Hz frequency with 0-100% Duty Cycle
10 Hz
Signal has a constant 10 Hz frequency with 0-100% Duty Cycle
1 Hz
Signal has a constant 1 Hz frequency with 0-100% Duty Cycle
0.1 Hz
Signal has a constant 0.1 Hz frequency with a 0-100% Duty Cycle
Signal Type
Active LOW When the output is active, it is pulled to ground (LOW)
Active HIGH When the output is active, it is in a high impedance state
20 % Duty Cycle
Example shows a PWM output signal configured
with a 100 Hz frequency and active HIGH
outputs. The duty cycle has been set to 20%.
100 Hz
Figure 16: PWM function diagram
20 % Duty Cycle
Figure 15: SYNC interface output type selection
