Curtis 1244 - Setting the Unloaded Vehicle Top Speed

Curtis 1244 Manual, Rev. E
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➂ Setting the Unloaded Vehicle Top Speed
e controller and vehicle should be configured as follows prior to setting the
maximum unloaded vehicle speed:
• Max Speed = 100%, all modes
• Drive Current Limit as established in tuning procedure ➁
• Field Map = 50%
• Field Map Start = 50% of the specified drive current limit
• Field Min = manufacturer’s specified minimum or 3 amperes
• Load Comp = 0
• e vehicle should be unloaded
• e vehicle battery should be fully charged.
e vehicle should be driven on a at surface in a clear area during this proce-
dure. Since the vehicle may initially be traveling at speeds in excess of the final
intended speed, precautions should be taken to ensure safety of test personnel
and anyone in the test area.
 1. Select the programmer’s Program Menu and scroll down until
the Field Min parameter is at the top of the display.
 2. Power up the vehicle and apply full throttle. While driving the
vehicle with full throttle applied, adjust the Field Min parame-
ter value to set the desired top speed. Increasing the Field Min
value decreases the vehicle’s top speed; decreasing the Field Min
value increases the vehicle’s top speed.
CAUTION: Do not decrease
the Field Min parameter value below the motor manufacturer’s
recommended minimum field current value, and do not increase
it above 10 amps. : If the Field Min value is too low, the
vehicle speed may oscillate or surge even at constant throttle. If
oscillation or surge is observed, increase the Field Min value until
the vehicle speed remains constant at constant throttle.
 3. If the Field Min parameter value is increased to 10 amps and the
vehicle top speed has still not been sufficiently reduced, the Max
Speed parameter should be used to bring the vehicle top speed
down to the desired level. First, decrease the Field Min parame-
ter, setting it to optimize smooth starting. en adjust the Max
Speed parameter per Step 4 to bring the vehicle top speed down
to the desired level. : If the Field Min parameter is set too
high, the high initial torque created by the high field current
may cause overly abrupt starts; this is why we recommend using
the Max Speed parameter in those cases where a moderate Field
Min setting does not sufficiently reduce the vehicle top speed.
6 — VEHICLE PERFORMANCE ADJUSTMENT