4
Analog Inputs
Configuration
Type 2 Alarms are always enabled (not configurable). Type 1 Alarms will always
be displayed in [Drive Alarm 1], but can be configured to either mask or allow
specific alarms from a) turning on the “Alarm” bit within the [Drive Status 1]
parameter and b) turning on a digital output when [Digital Outx Sel] is set to
“Alarm.”
For each Alarm Config bit,
0 = alarm disabled
and
1 = alarm enabled
.
Analog Inputs
Possible Uses of Analog Inputs
The analog inputs provide data that can be used for the following purposes:
•
Provide a value to [Speed Ref A] or [Speed Ref B].
•
Provide a trim signal to [Speed Ref A] or [Speed Ref B].
•
Provide a reference when the terminal block has assumed manual control of the
reference
•
Provide a reference and/or feedback for the PI loop. See "Process PID Loop" on
page 77
.
•
Provide an external and adjustable value for the current limit and DC braking
level
•
Start and Stop control using the Sleep/Wake mode.
•
Provide a value to [Torque Ref A] or [Torque Ref B].
Analog Scaling
[Analog In x Lo]
[Analog In x Hi]
A scaling operation is performed on the value read from an analog input in order to
convert it to units usable for some particular purpose. The user controls the scaling
by setting parameters that associate a low and high analog value (e.g. in volts or
mA) with a low and high target (e.g. Hz).
For many features such as Current Limit and DC Brake Level, the target scaling
values are fixed (not adjustable) to the minimum and maximum of the selected
function. However, the PowerFlex 700 contains “Scale Blocks” for additional
flexibility (refer to
page 91
).
Drive Alarm
1
1
1
Alarm Config
↓
↓
↓
1
0
0
↓
X
X
Active
Alarm
Inactive
Alarm
Inactive
Alarm
70EC
700VC
700H
✔ ✔