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Motor Controllers

Permanent Magnet Motor Speed Controller

Models 1228
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Permanent Magnet Motor Speed Controller

Models 1228

The Curtis Model 1228 Permanent Magnet Motor Speed Controller provide smooth and 

precise operating control, providing maximum user confidence. Model 1228 fully complies 

with European and US regulations and is fully programmable.

Ideal for OEM applications on three or four wheeled mobility aids, such as scooters, and for 

light industrial equipment such as sweepers and scrubbers.

FEATURES

▶ Four quadrant, full bridge solid-state design.

Meets or complies with relevant US and 

International Regulations

▶ The Curtis Model 1228 motor speed controller is designed 

to allow vehicle compliance with the EMC directive 

89/336/EEC.

▶ Designed to meet ANSI/RESNA WC14/21, ISO 7176-14, 

ISO 7176-21 and EN 1284.

▶ All software documentation needed to support 510K 

FDA filing is available.

Fully Programmable

▶ Easily adapted to meet many specific scooter, sweeper 

scrubber or light industrial equipment applications.

▶ Seat lift function is programmable to allow a single 

controller to implement traction and lift functions.

▶ Use of an electromagnetic brake is user selectable 

depending upon the type of application.

Easy to Install, Set-Up and Diagnose

▶ Standard 18-pin Molex Mini-fit Jr. logic connectors 

makes wiring simple and inexpensive.

▶ Internally protected against damage due to possible 

mis-wiring during installation.

▶ Can be interfaced with normal or inverted, wigwag 

(center off), single ended (speed pot and direction switch), 

and 0-5V throttle types, including limited range throttles 

down to 500Ω full stroke.

▶ Auxiliary B+ and B- terminals and an inhibit input for 

connecting to a battery charger.

▶ Diagnostic information (throttle faults, low battery, etc.) 

is available through dash-mounted LED flash codes and 

Curtis handheld programmers.

Powerful Safety Features

▶ Inhibit input prevents driving during charging.

▶ Control monitoring functions prevent driving with a 

defective throttle or associated wiring.

▶ Fault monitoring capability of electromagnetic brake 

functions is OEM selectable for individual vehicle 

requirements.

▶ If the keyswitch signal is turned Off while driving, the 

vehicle will decelerate normally, rather than stopping 

abruptly.

▶ Where electromagnetic brake is used, push input 

electrically releases brake for key-on pushing.

▶ If the vehicle is allowed to freewheel, the controller 

will automatically limit the maximum speed to a preset 

low speed.
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Permanent Magnet Motor Speed Controller

Models 1228

▶ A user supplied external warning beeper can be installed 

to alert bystanders when moving in reverse direction.

▶ The braking current limit is not decreased with high 

temperature, allowing the controller to provide maximum 

braking on extended downslopes.

Smooth, Secure Driving Feel

▶ The feel of advanced closed-loop control algorithms gives 

the operator confidence in the handling, operation and 

control of the vehicle, whether it is driving at full speed, 

on a steep hill or inching over a curb.

▶ Provides superior low speed control by compensating 

for both motor and controller losses.

▶ The motor current limit is smoothly reduced as the 

controller heats up beyond thermal limits, making 

available the maximum safe power under all conditions.

▶ With the electromagnetic brake selected, the controller 

varies the brake operation to provide smooth and 

secure stops.

▶ Provision for a separate speed limit pot allows smooth, 

linear adjustment of top speed.

▶ Gear softening compensates for slack in worn transaxles 

to provide smooth transitions.

Designed and Built for Optimum Reliability, 

Convenience and Economy

▶ Conservative components rating provides years of troublefree operation, and lower warranty costs.

▶ Power Saver shuts the controller Off after a programmable 

time preserving the battery.

▶ MultiModeTM control allows the user to select two entirely 

different sets of driving parameters for different driving 

modes, such as indoor and outdoor use.

▶ Battery Discharge Indicator (BDI) driver provides battery 

state-of-charge on a simple, user supplied voltmeter.

▶ Appropriate mounting or shielding is required to prevent 

exposure of controller electronics when used in wet or 

high particulate environments. Environmental rating of 

controller is IP40.

FEATURES continued
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Permanent Magnet Motor Speed Controller

Models 1228

DIMENSIONS mm

B+ B- M2 M1 LOGIC PROG

4.8 DIA, 2 PLCS

156 

6.8

6.8

43

91

SPECIFICATIONS

Model

Voltage

Rating

(Volts)

15 Second 

(Amps)

Drive Current 

Rating 

1 Minute* 

(Amps)

1 Hour* 

(Amps)

Undervoltage 

Cutback

(Volts)

Overvoltage

Cutoff

(Volts)

1228-24XX 24 70 70 35 17 36

1228-25XX 24 90 90 40 17 36

1228-29XX 24 110 110 40 17 36

1228-34XX 36 70 70 35 26 48

* Typical value, application dependent.
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Permanent Magnet Motor Speed Controller

Models 1228

TYPICAL WIRING DIAGRAM

is a trademark of Curtis Instruments, Inc. Specifications subject to change without notice ©2016 Curtis Instruments, Inc. 50053 REV G 9/16

WARRANTY Two year limited warranty from time of delivery.

BS

HORN

MODE SELECT

KSI

PUSH

REVERSE

J10-7

J10-3

J10-13

J10-8

J10-17

BRAKE

BRAKE

- J10-6

R

(OPTIONAL)

INHIBIT

+

J10-1

J10-10

J10-11

J10-2

J10-12

J10-18

J10-9

STATUS

BDI

J10-14

B -

B +

B +

B -

H

J10-16

J10-5

J10-15

J2

J1

J3

J4

J5

B+

J6

M1

M2

**OPTIONAL SWITCH OPERATED BY MECHANICAL

BRAKE RELEASE

EM BRAKE

T

SEAT LIFT SWITCH

(OPTIONAL)

NC

K1

J9-1

J9-3

Rx DATA

Tx DATA

GROUND J9-2

+15V J9-4

HORN

SEAT LIFT

(OPTIONAL)

TRACTION

**

BDI

BATTERY

CHARGER

THROTTLE

CONTROL

SPEED LIMIT POT SPEED LIMIT POT

STATUS LED

1228

CONTROLLER

POT HIGH

POT WIPER

POT LOW

J10-4