Wesley BC-6200-8SA - Manual (Page 45)

Curtis 1268 Manual, Rev. D
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step 4. In this case, the vehicle’s top speed is being limited by the field
mapping parameters. Observe the Arm Current in the Monitor
menu, and set the
FIELD MAP START to a value above the Arm Cur-
rent reading. Reduce the M1 FWD FLD MIN until the Speed Input
shows the programmed maximum speed (i.e., the speed set by
M1 FWD SPEED ) and the Arm PWM reading drops below 100%,
indicating that the controller is in closed loop speed control.
When the vehicle is unloaded the controller will output a lower
value of Arm PWM to maintain this speed.
Do not set the field mapping parameters outside the motor’s
safe commutation limits.
step 5. Repeat from Step 1 for the Mode 2 forward speed and for reverse
speed. Separate field minimum parameters are provided for all
three speeds (
M1 FWD SPEED , M2 FWD SPEED , REV SPEED ).
5
Confirming Loaded Vehicle Speed on Downhill Grade
step 1. Set the following parameters:
• REGEN C/L = maximum specified by the motor specs
• NEG FLD MAP EN = at or below REGEN C/L
• NEG FIELD MAX = FIELD MAX (as set in procedure 3, step 6)
• M1 BRAKE END = at least 1–2 mph or km/h below M1 FWD SPEED
• M1 BRAKE MAX = 100%.
step 2. With the vehicle fully loaded, drive down the steepest required
grade. Observe the Arm Current displayed in the Monitor menu
(it will be a negative value). This value is the regen current re-
quired to prevent exceeding the programmed top speed. It is an
important value to be aware of when adjusting the brake map-
ping parameters for optimum compression braking feel.
If the vehicle top speed is exceeded, increase the NEG FIELD
MAX and NEG FLD RAMP or decrease NEG FLD MAP EN to help provide
additional braking torque earlier.
See brake mapping examples on page 41.
step 3. Repeat the procedure for the Mode 2 forward speed and for
reverse speed. Separate brake mapping parameters are provided
for each speed (
M1 FWD SPEED , M2 FWD SPEED , REV SPEED ).
5 — TUNING GUIDE