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2- and 3--Channel Brushless DC Servo Controller
Hardware Limit Switches
The operation of the limit switches is inherent in the design of the associated stage or
actuator. The following parameters notify the system to the action of the switches
when contact is made. Select Rev Switch or Fwd Switch as required, then select the
relevant operation.
Switch Makes
- The switch closes on contact
Switch Breaks
- The switch opens on contact
Ignore/Absent
- The switch is missing, or should be ignored.
Not Applicable
- Limit switches are not applicable.
Motor
These parameters are used to set the 'resolution' characteristics of the DC motor
connected to the selected channel. The resolution of the motor, combined with other
characteristics (such as gearbox ratio) of the associated actuator or stage,
determines the overall resolution.
Steps Per Rev
- The number of encoder counts per revolution of the DC servo motor
(minimum '1', maximum '10,000').
For linear driven stages (e.g. MLS203) this parameter is set to ‘1’ and cannot be adjusted.
Gearbox Ratio
- The ratio of the gearbox. For example, if the gearbox has a reduction
ratio of X:1 (i.e. every 1 turn at the output of the gearbox requires X turns of the motor
shaft) then the Gearbox Ratio value is set to X. (minimum '1', maximum '1000').
For linear driven stages with no gearbox (e.g. MLS203) this parameter is set to ‘1’ and
cannot be adjusted.
Persist Settings to Hardware -
Many of the parameters that can be set for the BBD10x
series drivers can be stored (persisted) within the unit itself, such that when the unit
is next powered up these settings are applied automatically. This is particularly
important when the driver is being used manually via a joystick, in the absence of a
PC and USB link. The
Min Pos, Max Pos, and Velocity
parameters described
previously are good examples of settings that can be altered and then persisted in the
driver for later use.
To save the settings to hardware, check the ‘Persist Settings to Hardware’ checkbox
before clicking the ‘OK button.
Note
The
Gearbox Ratio
parameter is applicable only to motors fitted with a
gearbox.
Note
The ‘Steps Per Rev’ and ‘Gearbox Ratio’ parameters, together with the
‘Pitch’ and ‘Units’ parameters are used to calculate the calibration factor
for use when converting real world units to encoder counts.
The correct default values for Steps Per Rev and Gearbox Ratio are
applied automatically when the software is booted up.