Control Techniques Epsilon EP-P, Reference Manual

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Epsilon EP-P Drive Reference Manual
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www.controltechniques.com Revision: A4
If the user decides to put a 5:1 reducer on the system, the user simply needs to change the Characteristic Length.
Now the belt travels 4.71" in 5 motor revolutions.
Keep in mind that the characteristic length is always a whole number and the valid range is from 1 to 2000.
NOTE
User Units may affect end motor speed and could cause trajectory faults.
Because of internal math in the Epsilon EP-P drive, some user unit combinations may cause a drive trajectory faults. The maximum motor
velocity allowed by the drive is detailed under the distance section of the User Units View and is labeled “User Unit Limited Speed”. When the
user unit setup is altered in such a way that the maximum motor speed allowed by the drive is less than the maximum speed allowed by the
chosen motor, the readout of maximum motor speed allowed by the drive changes to have a red background. If a configuration is downloaded
to the drive with a red background on the “User Unit Limited Speed”, the drive will obtain a trajectory fault at speeds near this velocity. To
alleviate this issue, simply remove decimal places from your user units, and/or change the characteristic distance (numerator) of your scaling
parameters to be a smaller number that it was. The red background indicating trajectory faults will go away when the user unit setup is scaled
for a realistic accuracy based on the encoder counts per revolution.
3.5.2 Velocity Group
Enable Separate Distance Units Check Box
If selected (enabled), separate distance and velocity units, name and scaling will be enabled. If not enabled, the velocity units, name and
scaling will be defined by the Distance Group.
Scaled Distance Name
If the user wants the velocity units to have a different distance scaling than the distance units a name can be entered here up to 10 characters.
For example, the user distance units name could be inches while the velocity units name is feet per minute.
Velocity Distance Units Scale Factor
This parameter scales the Velocity Distance Units back to actual distance units. To do this, enter the number of distance user units that are
equal to one velocity scaled distance unit.
Separate Distance Units Example:
A user has an application using a leadscrew with a 0.5"/turn lead. The user wants to have Distance Units of Inches, but wants Velocity Units of
Feet so motion can be programmed in feet/minute.
Distance Units Name — Inches
Enable Separate Distance Units — Select check box (enabled)
Scaled Distance Name — Feet
Velocity Distance Units Scale Factor — # of Distance Units / 1 Scaled Distance Unit
1 Foot = 12 Inches
Velocity Distance Units Scale Factor = 12
Time Scale List Box
The time can be one of two values: seconds or minutes. This selection sets the real-time velocity time scale.
Decimal Places
The number of decimal places set in this parameter determines the number of digits after the decimal point used in all real-time velocity
parameters throughout the software. Using a high number of decimal places will improve velocity resolution, but will also limit the maximum
velocity. You can select from zero to six decimal places of programming resolution.
3.5.3 Acceleration Group
Time Scale List Box
From this list box, select the acceleration time scale to be used for all real-time profiles. The time scale selected will be used for both
acceleration and deceleration parameters. You can select from milliseconds or seconds.
Decimal Places
The number of decimal places set in this parameter determines the number of digits after the decimal point used in all real-time accel/decel
parameters throughout the software. Using a high number of decimal places will improve accel/decel resolution, but will also limit the
maximum accel/decel rate. You can select from zero to six decimal places of programming resolution.
3.5.4 Torque Group
Units Name
10-character name for the torque user units.
Decimal Places
The number of decimal places set in this parameter determines the number of digits after the decimal point used in all torque parameters
throughout the software. Using a high number of decimal places will improve torque resolution, but will also limit the maximum torque. You can
select from zero to six decimal places of programming resolution.
Scaling
The amount of torque in user torque units will be set equal to the Percent Continuous Current. This parameter is used to scale the actual
Scaling
Characteristic Distance = 4.712
Characteristic Length = 5
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