Automation Direct DURApulse GS4 User Manual page 210

Chapter 4: AC Drive Parameters
a i
nalog nPut
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 P4.09 must be set to enable
reverse motion.
When calculating the values for the Analog Input using reverse motion, polarity matters in the
Bias/Offset Parameter (P4.10, P4.15, or P4.19) AND in the Polarity Parameter (P4.11, P4.16, or
P4.20). If both parameters are negative, the resulting offset will be positive (double negatives).
If a negative offset is required, either the Bias/Offset value OR the Polarity Parameter needs
to be negative (not both). If your PLC does not handle negative values easily, use the Polarity
Parameter to create a negative bias/offset.
• Minimum Frequency Reference = -60Hz (reverse)
• Maximum Frequency Reference = 60Hz
For AI1, AI2, and AI3: P4.24 (AI V/Hz Calculated Selection) MUST BE SET TO ZERO (All Inputs
Use Bias and Gain) TO ENABLE BIAS AND GAIN CALCULATIONS.
Calculations (see
A) Drive Maximum Output Frequency = P0.04 = (1750 rpm / 1750 rpm) x 60Hz = 60Hz
B) Analog Offset % = [ (-60Hz) / (60Hz) ] x 100 = -100%
Analog Input (AIx)
AIx Bias Parameter
The negative (-) value for the Analog Offset shows that you can use either a negative value in the
Offset/Bias Parameter (P4.10, P4.15, or P4.19) or a negative setting in the Polarity Parameter
(P4.12, P4.17, or P4.21). Do not put a negative into both.
C) Analog Gain % = [ (60Hz – (-60Hz)) / 60Hz ] x 100 = 200% = AIx Input Gain
Analog Input
Polarity
AIx Gain Parameter
D) Mid-point Frequency = [ (60Hz – (-60Hz)) / 2 ] + (-60Hz) = 0Hz
Parameter Settings
Analog Input
Polarity
AIx Bias Parameter
AIx Polarity Parameter
AIx Gain Parameter
Reverse Run Parameter
Drive Max Output Freq
* This example uses Bias = -100% and Positive Bias Polarity.
The example will work exactly the same with Bias = +100% and a Negative Bias Polarity.
Examples
• Output Freq = [ (Analog_In%) x (Gain%) + (Bias%) ] x
• For AI1 set to 0~10V, and an analog input of 5 Volts:
Output Freq = [ (5/10) x (2�00) + (-1�00) ] x 60Hz = 0Hz
• For analog input of 10 Volts:
Output Freq = [ (10/10) x (2�00) + (-1�00) ] x 60Hz = 60Hz
Page 4–116
P e 4: F
araMeter xaMPle
page 4–112 for formulas)
AI1
P4�10
AI1
Positive (+)
P4�12
AI1 or
Positive (+) Positive (+)
P4�10
P4�11
P4�12
Max_Out (Hz)
DURA
r o
orward and everse Peration
AI2 AI3
P4�15 P4�19
AI2
Positive (+) Positive (+)
P4�17 P4�21
AI2 or AI3
Positive (+) Negative (-)
P4�15 P4�19
P4�16 P4�20
P4�17 P4�21
P4�09
P0�04
GS4 AC Drive User Manual – 1st Ed, Rev A - 10/20/2017
pulse
AI3
Negative (-)
P4�22
Parameter Settings
-100�0% *
1: Positive Offset *
P4�22 200�0%
1: AI Bias FWD/REV
60Hz
Results
Maximum
Output 60Hz
Frequency
0Hz
-60Hz
0V 5V
-10V 0V
0mA 10mA
4mA 12mA
Forward
Reverse
10V
10V
20mA
20mA