The Similarly Stimulated Saturn

F e a t u r e s
• High frequency switching and ultra low voltage drop provides
very high efficiency and quiet operation. Costs, heatsinking
requirements and motor and battery losses are reduced. Low
end torque, range and battery life are increased.
• Environmental protection provided by a sealed (factory
serviceable), rugged, anodized aluminum extrusion housing.
Simple mounting and wiring with push-on type connectors for
control signals. Plated solid copper busses used for all power
connections.
• Thermal protection and compensation circuit provides undertemperature
cutback, constant current limit over operating
range, and linear rollback in over-temperature. No sudden
loss of power under any thermal conditions.
• Frequency shifting from 15 kHz to 1.5 kHz at low throttle
settings provides improved protection against stalled motors.
• Heavy duty power base in 1231C contains additional active
devices to improve power handling capability.
• Potentiometer fault protection circuitry disables the controller
if the throttle wires become open.
• High Pedal Disable prevents controller operation if the key
switch is turned on while throttle is applied.
• Optional heatsink (p/n 16286) for model 1231C controller
improves thermal capability.
• No adjustments are required.
• Simple installation — Uses a two wire throttle potentiometer.
S P E C I F I C AT I O N S
• Frequency of Operation: 15/1.5 kHz
• Standby Current: less than 30 mA
• Ambient Operating Temperature Range: -25°C to 50°C
• Controller Temperature Cutback Point: -25°C and +85°C
D ESC R I P T I O N
The Curtis PMC models 1231C and 1221C motor speed controllers
provide smooth, silent, efficient and cost effective speed control for
on-road electric vehicle applications. These controllers utilize power
MOSFET technology, pioneered by Curtis PMC, to provide benefits
unavailable with older speed control systems.
A P P L I C AT I O N
The Curtis PMC models 1231C and 1221C are high power,
heavy duty MOSFET electronic motor speed controllers which
are ideal for use in electric commuter vehicles, light delivery
trucks, and other vehicles utilizing up to 144 volts.
www.curtisinstruments.com
M- A2
B- B+
MA2
B- B+
37 (1.5")
80 (3.2")
3.3 (0.13")
15 (0.6") 150 (5.9")
180 (7.1")
165 (6.5")
277 (10.9")
203 (8.0")
Control
Wiring
Fuse
Circuit
Breaker
Throttle
Pot
S1
S2
Motor
Field
A2 A1
+
–
Main
Motor
Armature
Key
Switch
Throttle
Switch
Main
Contactor
KSI Relay
Auxiliary
Battery
–
+
Traction
Battery
309 (12.2")
94 (3.7")
173 (6.8")
175 (6.9")
M- A2
B- B+
220 (8.6")
Mounting Clips (6 supplied)
Optional Heatsink (p/n 16286)
72 (2.84") 165 (6.50")
200 (7.87")
UNDERVOLT
CUTBACK
(volts)
64
43
43
VOLTAGE
DROP
@ 100A
.30
.30
.50
1 HOUR
RATING
(amps )
225
225
150
5 MIN
RATING
(amps )
375
375
250
2 MIN
RATING
(amps )
500
550
400
CURRENT
(amps )
500
550
400
VOLTAGE
(volts)
96-144
72-120
CURTIS PMC
MODELS
1231C-86XX
1231C-77XX
1221C-74XX
KSI
MODELS 1231C/1221C
M O D E L C H ART
T Y P I C A L W I R I N G D I AG RAM
D I M E N S I O N S 1 2 3 1
WARRANTY Two year limited warranty from time of delivery.
D I M E N S I O N S 1 2 2 1
M- A2
B- B+
MA2
B- B+
37 (1.5")
80 (3.2")
3.3 (0.13")
15 (0.6") 150 (5.9")
180 (7.1")
165 (6.5")
277 (10.9")
203 (8.0")
Control
Wiring
Fuse
Circuit
Breaker
Throttle
Pot
S1
S2
Motor
Field
A2 A1
+
–
Main
Motor
Armature
Key
Switch
Throttle
Switch
Main
Contactor
KSI Relay
Auxiliary
Battery
–
+
Traction
Battery
309 (12.2")
94 (3.7")
173 (6.8")
175 (6.9")
M- A2
B- B+
220 (8.6")
Mounting Clips (6 supplied)
Optional Heatsink (p/n 16286)
72 (2.84") 165 (6.50")
200 (7.87")
UNDERVOLT
CUTBACK
(volts)
64
43
43
VOLTAGE
DROP
@ 100A
.30
.30
.50
1 HOUR
RATING
(amps )
225
225
150
5 MIN
RATING
(amps )
375
375
250