Curtis MultiMode 1207B Manual page 40

APPENDIX A: GLOSSARY
Fig. A-3 Ramp shape
(throttle map) for controller
with maximum speed set
at 60% and creep speed
set at 10%.
A-8
In Figure A-3, the creep speed is kept at 10% and the maximum speed setting
dropped to 60%.
100
90
80
70
60
50
CREEP SPEED
(10%)
40
30
20
10
0
0 10 20 30
In all cases, the ramp shape number is the PWM output at half throttle, as a
percentage of its full range. So, for example, in Figure A-3, a 50% ramp shape
gives 35% PWM output at half throttle (halfway between 10% and 60%). A
30% ramp shape gives 25% PWM at half throttle (30% of the range {which
is 50%, from 10% to 60%}, starting at 10% output, or {[.30 x 50%] + 10%}
= 25%).
Ramp start
The ramp start feature allows the vehicle to be started with a higher plug current
limit to prevent rolling downhill. Ramp start increases the plug current limit for
the selected direction only. When the opposite direction is selected, ramp start
will be canceled and a 3-step sequence must be followed to re-activate it:
step 1. select a direction for more than 1 second,
step 2. return to neutral, and
step 3. re-select the same direction.
Once the vehicle is operating in ramp start mode, it will continue to do so
until the opposite direction is selected for more than one second.
When the brake is first released, the ramp start current limit level will be
obtained when either direction is selected in plug braking mode. In ramp start
mode, either direction selected will allow the ramp start current limit level. This
condition remains until the other direction is selected for more than one second.
The new direction then becomes the decision direction, and the 3-step ramp
start sequence is required to regain the ramp start current limit level in plug.
The ramp start current limit is adjustable via the handheld programmer.
The Mode 1 and Mode 2 ramp start current limits can be set independently.
MAXIMUM SPEED
(60%)
40 50 60 70 80
THROTTLE (percent)
RAMP SHAPE
70%
60%
50%
40%
30%
20%
90 100
Curtis 1207B Manual