Data Sheet

Motor Channel Parameters
Advanced Digital Motor Controller User Manual 85
The current limit may be set using the supplied PC utility. The maximum limit is dependent
on the controller model and can be found on the product datasheet.
The limitation is performed on the Motor current and not on the Battery current. See “Bat-
tery Current vs. Motor Current” on page 30 for a discussion of the differences.
Selectable Amps Threshold Triggering
The controller can be configured to detect when the Amp on a motor channel exceed a
user-defined threshold value and trigger an action if this condition persists for more than a
preset amount of time.
The list of actions that may be triggered is shown in the table below.
TABLE 7-2. Possible Action List when Amps threshold is exceeded
Action
Applicable
Channel Description
No Action - Input causes no action
Safety Stop Selectable Stops the selected motor(s) channel until command is
moved back to 0 or command direction is reversed
Emergency stop All Stops the controller entirely until controller is powered
down, or a special command is received via the serial
port
This feature is very different than amps limiting. Typical uses for it are for stall detection
or “soft limit switches”. When, for example, a motor reaches an end and enters stall con-
dition, the current will rise, and that current increase can be detected and the motor be
made to stop until the direction is reversed.
Programmable Acceleration & Deceleration
When changing speed command, the controller will go from the present speed to the de-
sired one at a user selectable acceleration. This feature is necessary in order to minimize
the surge current and mechanical stress during abrupt speed changes.
This parameter can be changed by using the PC utility. Acceleration can be different for
each motor. A different value can also be set for the acceleration and for the deceleration.
The acceleration value is entered in RPMs per second. In open loop installation, where
speed is not actually measured, the acceleration value is relative to the Max RPM param-
eter. For example, if the Max RPM is set to 1000 (default value) and acceleration to 2000,
this means that the controller will go from 0 to 100% power in 0.5 seconds.
Important Warning
Depending on the load’s weight and inertia, a quick acceleration can cause consider-
able current surges from the batteries into the motor. A quick deceleration will cause
an equally large, or possibly larger, regeneration current surge. Always experiment
with the lowest acceleration value first and settle for the slowest acceptable value.