Curtis 1253 User manual

Manual
Model 1253
Hydraulic Pump Motor Controller
Read Instructions Carefully!
Specications are subject to change without notice.
© 2015 Curtis Instruments, Inc. ® Curtis is a registered trademark of Curtis Instruments, Inc.
© The design and appearance of the products depicted herein are the copyright of Curtis Instruments, Inc. 38329 Rev F 2/15
Curtis Instruments, Inc.
200 Kisco Avenue
Mt. Kisco, NY 10549
www.curtisinstruments.com

Blue Ox Rev. A, draft #1 [3 August 2007]
Curtis 1253 Manual, Rev. F iii
CONTENTS
1. OVERVIEW..............................................................................1
2. INSTALLATION AND WIRING ...........................................3
Mounting the Controller .....................................................3
Low Current Connections....................................................5
High Current Connections ..................................................6
Wiring: Standard Configuration..........................................7
Wiring: rottles...............................................................11
Contactor, Switches, and Other Hardware.........................13
3. PROGRAMMABLE PARAMETERS.....................................15
Speed Parameters................................................................16
Maximum Speed, SS1–SS4 .........................................16
rottle Maximum Speed............................................16
Minimum Speed..........................................................16
Acceleration Rate.........................................................16
rottle Parameters ............................................................16
rottle Type...............................................................16
rottle Deadband ......................................................17
rottle Maximum......................................................18
rottle Map...............................................................20
Final Speed Request Parameters .........................................22
SS Add Mode ..............................................................22
Final Add Mode ..........................................................23
SS High Speed On ......................................................24
Fault Parameters.................................................................25
Lift Lockout Type........................................................25
Lift Lockout, SS1–SS4 ................................................25
Lift Lockout, rottle..................................................25
rottle Fault Detection..............................................26
Startup Lockout...........................................................26
Undervoltage Parameters....................................................27
Low Voltage Cutback ..................................................27
Low Voltage Cutback Rate ..........................................27
Contactor Control Parameters ...........................................27
Pump Contactor Control ............................................27
Contactor Pull-in Voltage ............................................27
Contactor Holding Voltage..........................................27
SS4 Delay....................................................................28
Interlock Delay............................................................28
Precharge.....................................................................28
Precharge Delay...........................................................28
CONTENTS

iv Curtis 1253 Manual, Rev. F
CONTENTS
Current Limit Parameter....................................................29
Main Current Limit (x10A).........................................29
4. INSTALLATION CHECKOUT............................................30
5. DIAGNOSTICS AND TROUBLESHOOTING..................32
Programmer Diagnostics ....................................................32
LED Diagnostics................................................................34
6. MAINTENANCE...................................................................35
appendix aVehicle Design Considerations
appendix bProgramming Devices and Menus
appendix cSpecifications, Curtis 1253 Controller

Blue Ox Rev. A, draft #1 [3 August 2007]
Curtis 1253 Manual, Rev. F v
FIGURES
. 1: Curtis 1253 hydraulic system controller................................... 1
. 2: Mounting dimensions, Curtis 1253 controller ........................ 3
. 3a: Standard wiring configuration,
using Curtis 803 gauge for lift lockout..................................... 7
. 3b: Standard wiring configuration,
using Curtis 906 gauge for lift lockout..................................... 8
. 3c: Standard wiring configuration,
using Curtis 841 “Superspy” for lift lockout............................. 9
. 3d: Standard wiring configuration,
using Curtis enGage™IV for lift lockout............................... 10
. 4: Wiring for 2-wire 5kΩ–0 potentiometer (“Type 0”) .............. 12
. 5: Wiring for 2-wire 0–5kΩpotentiometer (“Type 1”) .............. 12
. 6: Wiring for single-ended 0–5V input (“Type 2”) .................... 13
. 7: Wiring for single-ended 1–10kΩ3-wire pot (“Type 3”) ........ 13
. 8: Eect of adjusting the throttle deadband parameter .............. 17
. 9: Eect of adjusting the throttle max parameter ....................... 19
. 10: rottle maps for controller
with maximum speed set at 100% ........................................ 20
. 11: rottle maps for controller
with maximum speed set at 80% .......................................... 21
. 12: Inuence of various parameters on controller
output response to throttle demand ...................................... 21
. 13: Speed conditioning ............................................................... 23
. 14: SS High Speed On speed conditioning ................................. 24
. 15: Bench test setup .................................................................... 31
FIGURES

vi Curtis 1253 Manual, Rev. F
TABLES
TABLES
 1: rottle wiper input (threshold values)................................ 11
 2: Programmable throttle input signal types............................. 17
 3: Programmable lift lockout signal types ............................... 25
 4: Precharge function and fault detection................................. 28
 5: Troubleshooting chart.......................................................... 33
 6: Status LED fault codes ....................................................... 34
 C-1: Specifications, 1253 controller .......................................... C-1

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 1
Blue Ox Rev. A, draft #1 [3 August 2007]
1 — OVERVIEW
OVERVIEW
e Curtis 1253 provides a cost-eective solution for control of high power
DC series-wound hydraulic pump motors. Its system integration features are
designed primarily for Class I and Class II material handling vehicles. Typical
applications include the pump systems of material handling trucks (counter-
balance trucks, reach trucks), aerial lift platforms (scissor lifts, articulating/
telescoping booms), and other industrial vehicles.
e 1253 accepts inputs from up to four Speed Select switches and also
from an analog throttle. Its internal microprocessor-based logic controller pro-
vides maximum exibility at minimum cost. Its performance characteristics can
be tailored through an array of programmable parameters.
e 1253 controller is fully programmable through a Curtis handheld
programmer or PC Programming Station. e programming device provides
diagnostic and test capability in addition to conguration exibility.
1
Fig. 1 Curtis 1253
hydraulic pump motor
controller.
Like all Curtis motor controllers, the 1253 oers superior operator control of
motor speed and torque.
Smooth and Quiet Control
✓Programmable acceleration rates provide smooth application
of pump motor torque
✓15.6 kHz PWM frequency for near-silent operation.

2Curtis 1253 Manual, Rev. F
1 — OVERVIEW
Programmable Flexibility
✓Easily programmable through a Curtis programming device
✓Four Speed Select inputs (SS1–SS4) with individually programmable
top speeds
✓Programmable throttle input for precise speed control with a variety
of signal sources
✓Programmable turn-o delay allows SS4 to be used for power steering
✓Adjustable minimum speed setting to ensure pump lubrication
and to maintain steering system pressure
✓SS High Speed On mode enhances speed stability (1253-4804 only).
Robust Safety and Reliability
✓Interlock feature disables the controller when operator is not present
✓Programmable startup lockout prevents inadvertent operation
✓Seamless integration with Curtis gauges (models 803, 841, 906, and
enGage™IV) for lift lockout function
✓Lift lockout disables the controller at low battery state of charge
✓Redundant watchdog timer circuits ensure proper software operation
✓External Status LED output for easy troubleshooting
✓Short-circuit protection on main contactor driver
✓Precharge control prevents pitting of contactor tips at startup
✓ermal cutback provides protection to the controller
✓Rugged housing meets IP54 environmental ratings
✓Full-power operation over the -40°C – 80°C heatsink temperature
range.
Familiarity with your Curtis controller will help you install and operate it prop-
erly. We encourage you to read this manual carefully. If you have questions,
please contact the Curtis office nearest you.

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 3
Blue Ox Rev. A, draft #1 [3 August 2007]
INSTALLATION AND WIRING
MOUNTING THE CONTROLLER
e 1253 controller can be oriented in any position, and meets the IP54 ratings
for environmental protection against dust and water. However, the location
should be carefully chosen to keep the controller clean and dry. If a clean,
dry mounting location cannot be found, a cover must be used to shield the
controller from water and contaminants.
e controller’s outline and mounting hole dimensions are shown in
Figure 2. When selecting the mounting position, be sure to also take into
consideration that access is needed at the end of the controller to plug the
programmer into its connector.
To ensure full rated power, the controller should be fastened to a clean,
at metal surface with four 6 mm (1/4") diameter screws, using the holes
2
2 — INSTALLATION & WIRING: Controller
Fig. 2 Mounting dimensions, Curtis 1253 controller.
7.2 (0.28) dia. 16 (0.63)
196 (7.72)
31.3 (1.23) 133.3 (5.25)
146.0 (5.75)
130.3 (5.12)
8.5 (0.33) dia.
25 ×19 × 3
(1.0 × 0.75 × 0.12)
5.0
(0.20)
77 (3.03)
Dimensions in millimeters and (inches)

4Curtis 1253 Manual, Rev. F
2 — INSTALLATION & WIRING: Controller
Working on electrical systems is potentially dangerous. You should
protect yourself against uncontrolled operation, high current arcs, and
outgassing from lead acid batteries:
UNCONTROLLED OPERATION — Some conditions could cause the hydraulic
pump system to run out of control. Disconnect the motor or make sure
the pump system has enough room to operate before attempting any
work on the motor control circuitry. Note: If the wrong throttle input
signal type is selected with the programming device, the pump system
may suddenly begin to operate.
HIGH CURRENT ARCS — Batteries can supply very high power, and arcs can
occur if they are short circuited. Always open the battery circuit before
working on the motor control circuit. Wear safety glasses, and use
properly insulated tools to prevent shorts.
LEAD ACID BATTERIES — Charging or discharging generates hydrogen gas,
which can build up in and around the batteries. Follow the battery man-
ufacturer’s safety recommendations. Wear safety glasses.
provided. Although not usually necessary, a thermal joint compound can be
used to improve heat conduction from the controller heatsink to the mounting
surface.
You will need to take steps during the design and development of your
end product to ensure that its EMC performance complies with applicable
regulations; suggestions are presented in Appendix A.
☞
CAUTION

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 5
Blue Ox Rev. A, draft #1 [3 August 2007]
LOW CURRENT CONNECTIONS
Two low current connectors are built into the 1253 controller. ey are located
on the end of the controller:
2 — INSTALLATION & WIRING: Controller
e 12-pin connector (J1) provides the logic control connections. e mating
connector is a 12-pin Molex Mini-Fit Jr. connector part number 39-01-2125
using type 5556 terminals.
17
6
12
13
24
J1
J2
1 2 3 4 5 6
7 8 9 10 11 12
e 4-pin connector (J2) is for the programmer—either the 1311 handheld
programmer or the 1314 PC Programming Station. A complete programmer
kit with the appropriate connecting cable can be ordered:
Curtis p/n 168961101 for the User Programmer (model 1307M-1101)
Curtis p/n 168962101 for the OEM Programmer (model 1307M-2101).
If a handheld programmer is already available but has an incompatible cable,
the 1253 mating cable can be ordered as a separate part: Curtis p/n 16185.
With a 1314 PC programming station, the 1309 interface box and cable connect
the computer to the controller:
p/n 117465704 1314-1101, 1314 PC Programming Station (User) CD-ROM
p/n 117465707 1314-4401, 1314 PC Programming Station (OEM) CD-ROM
p/n 16994001 1309 Interface Box
p/n 16185 Molex cable for 1309 Interface Box.
21
43
J1-1Keyswitch Input (KSI) input and return for main contactor coil
J1-2Pot High +5V supply
J1-3Pot Wiper pot wiper input (or 5V throttle input)
J1-4Pot Low to ground through 511 ohm resistor
J1-5Interlock input from operator-present switch, tied to B+
J1-6Status LED LED driver low-side output
J1-7SS1 Speed Select 1 input
J1-8SS2 Speed Select 2 input
J1-9SS3 Speed Select 3 input
J1-10 SS4 Speed Select 4 input
J1-11 Lift Lockout input to the inhibit lift feature
J1-12 Contactor main contactor coil driver low-side output
J2
J1
J2-1Rx Data
J2-2B-
J2-3Tx Data
J2-4 +15V
: e 1311 hand-
held programmer has
been superseded; if you
are using a more recent
model, please refer to its
documentation.

6Curtis 1253 Manual, Rev. F
2—INSTALLATION&WIRING: Controller
HIGH CURRENT CONNECTIONS
ree tin-plated solid copper bus bars are provided for the high current con-
nections to the battery (B+ and B‑)and the motor armature (M‑).
☞
CAUTION
WIRING: Standard Conguration
Figure 3 shows the typical wiring configuration for most applications. e in-
terlock switch is typically a seat switch, tiller switch, or foot switch. e throttle
shown is a 3-wire pot; other types of throttles can also be used.
Lift lockout can be provided through any of four Curtis gauges:
(a) Curtis 803
(b) Curtis 906
(c) Curtis 841 “Superspy”
(d) Curtis enGage™I V.
As each of these gauges is wired somewhat dierently to provide lift lockout,
four individual wiring diagrams are included (Figs. 3a, 3b, 3c, 3d).
Power Wiring
Motor wiring is straightforward, with the field’s S1 connection going to the
controller’s B+ bus bar and the armature’s A2 connection going to the control-
ler’s M‑ bus bar.
Control Wiring
e main contactor coil should be wired directly to the controller as shown in
Figure 3. e controller uses the main contactor coil driver output to remove
power from the controller and pump motor in the event of various faults. If
the main contactor coil is not wired to Pin 12, the controller will not be
able to open the main contactor in serious fault conditions.
B- B+
M-

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 7
Blue Ox Rev. A, draft #1 [3 August 2007]
2 — INSTALLATION & WIRING: Controller
Fig. 3a Standard wiring configuration,
Curtis 1253 controller with Curtis 803 providing lift lockout.
1253 CONTROLLER
RxDATA
J2-1
GROUND (B-)
J2-2
TxDATA
J2-3
+15V
J2-4
M
J1-5
BATTERY
INTERLOCK
B+
M-
1311 PROGRAMMER
B-
INTERLOCK
J1-6
SS1
SS2
SS4
STATUS
J1-7
J1-8
J1-9
POT HIGH
J1-2
POT WIPER
J1-3
POT LOW
J1-4
THROTTLE
POT
J1-10
STATUS
SS3
SPEED SELECT SWITCHES
KEYSWITCH
J1-1
KSI
J1-12
CONTACTOR
CONTACTOR
CURTIS 803
14
58
J1-11
LIFT LOCKOUT
803-8
803-5
803-4
803-3
Lift lockout is activated when the 803’s internal
relay between pins 3 and 4 is opened at 80%
battery discharge.
LOCKOUT TYPE should be programmed to 1.
A2
S1
SS1 SS2 SS3 SS4

8Curtis 1253 Manual, Rev. F
Fig. 3b Standard wiring configuration,
Curtis 1253 controller with Curtis 906 providing lift lockout.
1253 CONTROLLER
RxDATA
J2-1
GROUND (B-)
J2-2
TxDATA
J2-3
+15V
J2-4
M
J1-5
BATTERY
INTERLOCK
B+
M-
1311 PROGRAMMER
B-
INTERLOCK
J1-6
SS1
SS2
SS4
STATUS
J1-7
J1-8
J1-9
POT HIGH
J1-2
POT WIPER
J1-3
POT LOW
J1-4
THROTTLE
POT
J1-10
STATUS
SS3
SPEED SELECT SWITCHES
KEYSWITCH
J1-1
KSI
J1-12
CONTACTOR
CONTACTOR
CURTIS 906
1
4
J1-11
LIFT LOCKOUT
906-1
906-2
906-3
Lift lockout is activated when pin 3 of the 906
drops from 5 V to 0 V at 80% battery discharge.
LOCKOUT TYPE should be programmed to 0.
A2
S1
SS1 SS2 SS3 SS4
2
3
2 — INSTALLATION & WIRING: Controller

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 9
Blue Ox Rev. A, draft #1 [3 August 2007]
Fig. 3c Standard wiring configuration,
Curtis 1253 controller with Curtis 841 “Superspy” providing lift lockout.
1253 CONTROLLER
RxDATA
J2-1
GROUND (B-)
J2-2
TxDATA
J2-3
+15V
J2-4
M
J1-5
BATTERY
INTERLOCK
B+
M-
1311 PROGRAMMER
B-
INTERLOCK
J1-6
SS1
SS2
SS4
STATUS
J1-7
J1-8
J1-9
POT HIGH
J1-2
POT WIPER
J1-3
POT LOW
J1-4
THROTTLE
POT
J1-10
STATUS
SS3
SPEED SELECT SWITCHES
KEYSWITCH
J1-1
KSI
J1-12
CONTACTOR
CONTACTOR
CURTIS 841 “Superspy”
14
58
J1-11
LIFT LOCKOUT
841-6
841-5
841-4
841-3
Lift lockout is activated when the 841’s internal
relay between pins 3 and 4 is opened at 80%
battery discharge.
LOCKOUT TYPE should be programmed to 1.
A2
S1
SS1 SS2 SS3 SS4
2 — INSTALLATION & WIRING: Controller

10 Curtis 1253 Manual, Rev. F
Fig. 3d Standard wiring configuration,
Curtis 1253 controller with Curtis enGage™IV providing lift lockout.
1253 CONTROLLER
RxDATA
J2-1
GROUND (B-)
J2-2
TxDATA
J2-3
+15V
J2-4
M
J1-5
BATTERY
INTERLOCK
B+
M-
1311 PROGRAMMER
B-
INTERLOCK
J1-6
SS1
SS2
SS4
STATUS
J1-7
J1-8
J1-9
POT HIGH
J1-2
POT WIPER
J1-3
POT LOW
J1-4
THROTTLE
POT
J1-10
STATUS
SS3
SPEED SELECT SWITCHES
KEYSWITCH
J1-1
KSI
J1-12
CONTACTOR
CONTACTOR
CURTIS enGageTM IV
11
J1
J1-11
LIFT LOCKOUT
enGage IV MOSFET Output
enGage IV J1-2
enGage IV J1-1
Lift lockout is activated when the enGageTM IV’s
MOSFETOutput is pulled Low. The MOSFETOutput
is at pin J1-14, -15, or -16, depending on the
gauge’s configuration.
LOCKOUT TYPE should be programmed to 0.
A2
S1
SS1 SS2 SS3 SS4
20
110
J2
2 — INSTALLATION & WIRING: Controller

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 11
Blue Ox Rev. A, draft #1 [3 August 2007]
2 — INSTALLATION & WIRING: Throttles
WIRING: Throttles
Various throttles can be used with the 1253 controller. ey are categorized as
one of four types in the Program Menu.
Type 0: two-wire 0–5kΩpotentiometer throttles
Type 1: two-wire 5kΩ–0 potentiometer throttles
Type 2: single-ended 0–5V throttles
Type 3: single-ended three-wire 1kΩ–10kΩ pot throttles.
Table 1 summarizes the operating specifications for these four throttle types.
Table 1 WIPER INPUT: THROTTLE THRESHOLD VALUES
MINIMUM THROTTLE THROTTLE MAXIMUM
THROTTLE THROTTLE DEADBAND STARTUP MAX THROTTLE
TYPE PARAMETER FAULT (0% speed request) LOCKOUT (100% modulation) FAULT
0Wiper Voltage — 0.6 V out of deadband 4.5 V 5.7 V
Wiper Resistance — 0 kΩ5.0 kΩ7.5 kΩ
1Wiper Voltage — 4.5 V out of deadband 0.6 V 5.7 V
Wiper Resistance — 5.0 kΩ0 kΩ7.5 kΩ
2Wiper Voltage — 0 V out of deadband 5.0 V 5.5 V
Wiper Resistance — — — —
3Wiper Voltage 0.4 V 0.5 V out of deadband 5.0 V 5.5 V
Wiper Resistance — 0 kΩ5.0 kΩ—
Notes: The upper and lower deadbands are valid for nominal 5kΩpotentiometers or 5V sources
with the default Throttle Deadband and Throttle Max parameter settings of 0% and 100%
respectively. These values will change with variations in the Throttle Deadband and Throttle
Max parameter settings—see Section 3, pages 17 and 18.
The startup lockout threshold for all throttle types is set by the Throttle Deadband.
For potentiometers, the 1253 provides complete throttle fault protection that
meets all applicable EEC regulations. For voltage throttles, the 1253 protects
against out-of-range wiper voltages (see Table 1), but does not detect wiring
faults; it is therefore the responsibility of the OEM to provide full throttle fault
protection in vehicles using voltage throttles.
Wiring for the most common throttles is described below. If the throttle
you are planning to use is not covered, contact the Curtis office nearest you.
Note: In the text, throttles are identified by their nominal range (e.g.,
5kΩ–0 pot) and not by their actual operating range.

12 Curtis 1253 Manual, Rev. F
0–5k Ω Throttle (“Type 0”)
e 0–5kΩthrottle (“Type 0” in the Program Menu) is a 2-wire resistive throttle
that connects between the Pot Wiper and Pot Low pins, as shown in Figure 4.
Zero speed corresponds to 0Ωmeasured between the two pins and full speed
corresponds to 5 kΩ.
2 — INSTALLATION & WIRING: Throttles
Fig. 4 Wiring for
0–5k Ω throttle (“Type 0”).
If the total resistance between the Pot Wiper and Pot Low pins is greater
than 7.5 kΩ, the controller’s upper fault limit will be exceeded (see Table 1) and
the throttle’s input value will be zeroed. is provides broken wire protection,
and also serves as an indication that the potentiometer’s resistance has increased
beyond the acceptable range and that the pot therefore needs to be replaced.
5k Ω –0 Throttle (“Type 1”)
e 5kΩ–0 throttle (“Type 1” in the Program Menu) is a 2-wire resistive throttle
that connects between the Pot Wiper and Pot Low pins, as shown in Figure 5.
Zero speed corresponds to a nominal 5kΩmeasured between the two pins and
full speed corresponds to 0Ω.
If the total resistance between the Pot Wiper and Pot Low pins is greater
than 7.5 kΩ, the controller’s upper fault limit will be exceeded (see Table 1) and
the throttle’s input value will be zeroed. is provides broken wire protection,
and also serves as an indication that the potentiometer’s resistance has increased
beyond the acceptable range and that the pot therefore needs to be replaced.
Fig. 5 Wiring for 5k Ω –0
throttle (“Type 1”).
5kΩ–0
Pot Low input (Pin J1-4)
Pot Wiper input (Pin J1-3)
FASTER
0–5k
Ω
Pot Low input (Pin J1-4)
Pot Wiper input (Pin J1-3)
FASTER

Blue Ox Review of wiring diagrams [24 July 2007]
Curtis 1253 Manual, Rev. F 13
Blue Ox Rev. A, draft #1 [3 August 2007]
Single-Ended 0–5V Voltage Source (“Type 2”)
With this throttle (“Type 2” in the Program Menu) the controller looks for
a voltage signal at the Pot Wiper pin. Zero speed corresponds to 0V and full
speed to 5V.
2 — INSTALLATION & WIRING: Switches, etc.
Fig. 6 Wiring for
0–5V throttles (“Type 2”).
e active range for this throttle is from 0V (at 0% rottle Deadband) to
5.0V (at 100% rottle Max), measured relative to B-. e signal is measured
at the Pot Wiper pin. It is the responsibility of the OEM to provide appropriate
throttle fault detection for 0–5V throttles.
Single-Ended 1k Ω –10k Ω 3-wire pot (“Type 3”)
e 3-wire potentiometer is used in its voltage divider mode, with the voltage
source and return being provided by the 1253 controller. Pot High provides a
current limited 5V source to the pot, and Pot Low provides the return path.
Wiring is shown in Figure 7 and is also shown in the standard wiring diagrams,
Figure 3.
Fig. 7 Wiring for 3-wire
potentiometer throttle
(“Type 3”).
FASTER
1kΩ–10kΩ
Pot Wiper input (Pin J1-3)
Pot Low input (Pin J1-4)
Pot High output (Pin J1-2)
When a 3-wire pot is used, the controller provides full fault protection.
Potentiometers with total resistance values between 1kΩand 10 kΩcan be used.
CONTACTOR, SWITCHES, and OTHER HARDWARE
Main Contactor
A main contactor should be used with the 1253 controller. Otherwise, the
controller’s fault detection will not be able to fully protect the controller and
hydraulic system from damage in a fault condition. e main contactor allows
the controller and motor to be disconnected from the battery. is provides a
significant safety feature, because it means the battery power can be removed
+
-
B-
0–5V input (Pin J1-3)

14 Curtis 1253 Manual, Rev. F
from the hydraulic system if a controller or wiring fault results in battery power
being applied to the motor inappropriately.
e 1253 provides a low-side contactor coil driver (at Pin J1-12) for the
main contactor. e driver output is rated at 1 amp and is short-circuit protected.
It is recommended that a coil suppression diode be included, as shown in the
wiring diagrams. is protects the contactor coil driver from inductive voltage
kickback spikes when the contactor is turned o.
Keyswitch and Interlock Switch
e vehicle should have a master on/o switch to turn the system o when not
in use. e keyswitch input provides logic power for the controller.
e interlock switch, which is typically implemented as a seatswitch or a
hand/foot activated deadman switch, provides a safety interlock to ensure that
an operator is present in order for the system to run.
e keyswitch and interlock switch provide current to drive the main
contactor coil as well as the controller’s internal logic circuitry, and must be
rated to carry these currents.
Speed Select Switches
ese input switches can be any type of single-pole, single-throw (SPST) switch
capable of switching the battery voltage at 25 mA.
Reverse Polarity Protection Diode
For reverse polarity protection, a diode should be added to the control circuit.
is diode will prohibit main contactor operation and current ow if the battery
pack is accidentally wired with the B+ and B- terminals reversed. It should be
sized appropriately for the maximum contactor coil current required from the
control circuit. e reverse polarity protection diode should be wired as shown
in the standard wiring diagrams (Figure 3).
Circuitry Protection Devices
To protect the control circuitry from accidental shorts, a low current fuse (ap-
propriate for the maximum current draw) should be connected in series with
the battery feed to the keyswitch. Additionally, a high current fuse should be
wired in series with the main contactor to protect the motor, controller, and
batteries from accidental shorts in the power system. e appropriate fuse for
each application should be selected with the help of a reputable fuse manufac-
turer or dealer. e standard wiring diagrams (Figure 3) show the recommended
location for each fuse.
2 — INSTALLATION & WIRING: Switches, etc.