AutomationDirect DURAPULSE GS3-4030 - Page 118

Chapter 4: AC Drive Parameters
4–50
Example 4: Forward and Reverse Operation
In this example, the potentiometer (or other analog signal device) is programmed
to run a motor full-speed in both forward and reverse directions. The frequency
reference will be 0Hz when the potentiometer is positioned at mid-point of its
scale. Parameter P4.04 must be set to enable reverse motion.
• Minimum Frequency Reference = -60 Hz (reverse)
• Maximum Frequency Reference = 60 Hz
Calculations
A) Max Output Frequency = (1750 rpm / 1750 rpm) x 60 Hz = 60 Hz
B) Analog Offset % = (-60 Hz / 60 Hz) x 100 = -100%
C) Analog Gain % = ((60 Hz – (-60 Hz)) / 60 Hz) x 100 = 200%
D) Mid-point Frequency = ((60 Hz – (-60 Hz)) / 2) + (-60 Hz) = 0Hz
Parameter Settings
P4.01: 02 – Negative Input Offset Polarity
P4.02: 100 – 100% Analog Input Offset
P4.03: 200 – 200% Analog Input Gain
P4.04: 01 – Reverse Motion Enable
Results
Maximum Output
Frequency
60Hz
-60Hz
0Hz
Forward
Reverse
0V 5V 10V
-10V 0V 10V
0mA 10mA 20mA
4mA 12mA 20mA
The negative (-) value for the Analog Offset % shows that a negative offset is needed
for P4.01.
When calculating the values for the Analog Input using reverse motion, the reverse
frequency reference should be shown using a negative (-) number. Pay special
attention to signs (+/-) for values representing reverse motion.
DURAPULSE AC Drive User Manual
1st Ed. Rev. D 05/2013