Installation manual

10
Epsilon EP-B Base Drive Reference Manual
Analog Velocity Sub-Mode
The Analog Input receives an analog voltage which is converted to the Velocity Command Analog parameter using the
Full Scale Velocity, Analog Input Full Scale, and Analog Input Zero Offset parameters. The equation for this conversion
is:
Where:
VCA = Velocity Command Analog (RPM)
AI = Analog Input (volts)
AZO = Analog Input Zero Offset (volts)
FSV = Full Scale Velocity (RPM)
AFS = Analog Input Full Scale (volts)
The Velocity Command is always equal to the Velocity Command Analog in Analog Velocity mode. The Velocity
Command is the command received by the velocity closed loop control.
Analog Accel/Decel Limit
This feature in the Analog sub-mode allows you to limit the accel and decel rate when using the analog input for velocity
control. This makes it very simple to use the drive in high performance, variable speed, start-stop applications such as
Clutch-Brake replacements without requiring a sophisticated controller to control the acceleration ramps. In applications
which do not require the drive to limit the ramps such as when using an external position controller, the parameter can
be set to “0” (its default value). If the Analog Accel/Decel Limit parameter value is changed during a ramp, the new ramp
limit is imposed within the next servo loop update.
The Analog Accel/Decel Limit parameter is accessed on the Ramps view. Its range is 0.0 to 32700.0 ms/kRPM.
Preset Velocity Sub-Mode
Preset Velocity sub-mode provides up to eight digital Velocity Presets and associated Accel/Decel Presets. At any time
only one Velocity Preset can be selected. They are selected using the Velocity Preset 1, Velocity Preset 2 and Velocity
Preset 3 input functions (see table below).
* (0) = Inactive input function, (1) = Active input function
When one of the Velocity Presets is selected, the Target Velocity is set equal to the Preset Velocity value and the accel/
decel ramp rate is set to the Preset Accel/Decel value associated with that velocity preset.
If the Velocity Command Preset is not equal to the Target Velocity, an acceleration (or deceleration) ramp is in progress.
In this state, the Velocity Command Preset will be increased (or decreased) based upon the acceleration (or
deceleration) ramp rate of the selected velocity preset. During the acceleration/deceleration ramp, the At Velocity output
function is inactive.
If the Velocity Command Preset is equal to the Target Velocity, all ramping is complete, the Velocity Command Preset
is constant and the At Velocity output function is active.
The Velocity Command is always equal to the Velocity Command Preset in Preset Velocity sub-mode.
Velocity Preset 3 Velocity Preset 2 Velocity Preset 1
Selected Preset #
Velocity and Accel / Decel
000 0
001 1
010 2
011 3
100 4
101 5
110 6
111 7
AFS
FSV) AZO) ((AI
VCA
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