1205 electronic motor controller. Model 1204 has identical connections. Like all Curtis PMC 1200 series controllers, the 1204/1205 models offer superior operator control of the vehicle’s motor drive speed. Key features of the 1204/1205 controllers include: Infinitely variable drive and brake control Power MOSFET design provides high efficiency (for reduced motor...
Tin-plated solid copper bus bars Push-on connectors for control wiring Familiarity with your Curtis PMC controller will help you to install and operate it properly. We encourage you to read this manual carefully. If you have questions, please contact the Curtis office nearest you.
≈4400 ohms) will work with the standard throttle input. For other types, contact your Curtis office. If a Curtis PMC potbox is used, it must be mounted so as to allow connection between the potbox lever arm and the vehicle accelerator linkage.
WIRING: = throttle input = switch, common is not used with BLACK BLUE GREEN = throttle input = switch, normally open 1204/1205 controllers) WHITE ORANGE Dimensions in millimeters and (inches) Curtis PMC footpedal FP-2. Fig. 4 Curtis PMC 1204/1205 Manual...
HARDWARE INSTALLATION OTHER HARDWARE The recommended hardware for a typical 1204/1205 controller installa- tion is shown in Figure 5. Contactors should be mounted in a clean, dry location. If such a location is unavailable, a cover should be used to deflect dirt and water splash.
Albright SW80 or SW180 (available from Curtis). A coil suppression diode, such as a Curtis PMC p/n MP-1 (which is rated at 100 volts, 3 amps), should be used on the contactor coil.
(typically 10 amps) connected in series with the B+ feed to the control circuitry wiring is recommended. Power Wiring Fuse To protect the power wiring circuit, a fuse appropriate for the controller’s rated current (see Appendix C) is recommended. Curtis PMC 1204/1205 Manual...
Failure to use the double-wrench technique could cause undue strain to be placed on the internal connections, and could also result in cracked seals around the bus bars. Curtis PMC 1204/1205 Manual...
– Basic wiring configuration, Fig. 6 Curtis PMC 1204/1205 controller. WIRING: SERIES MOTORS Figure 6 is a schematic of the configuration shown in Figure 5. Wired this way, the vehicle will plug brake if the direction is changed with the vehicle moving and the throttle applied.
field winding. Be careful if you are replacing this type of controller. When using the Curtis PMC controller it is essential that the field be reversed and that the armature be connected directly to the controller’s B+ and A2 terminals, because the plug diode inside...
2×SPDT contactors (see Figures 6 and 7). As previously noted in the section on standard power wiring, when using the Curtis PMC controller it is essential that the field be reversed and that the armature be connected directly to the controller’s B+ and A2 terminals, because the plug diode inside is connected to these terminals.
field cables by rotating a movable contact bar. The configura- tion shown is typical; many variations are in use. Power wiring Fig. 9 FUSE MAIN for reversing with mechanical forward/reverse PRECHARGE RESISTOR (250 Ω, 5 W) switch arm. – Curtis PMC 1204/1205 Manual...
Throttle Pot Wiring Standard potbox wiring If the throttle input to the controller is from a Curtis PMC potbox or footpedal, the wiring is simple: just connect the two wires of the potbox/ footpedal cable to the two push-on terminals of the controller, as shown in Figure 6.
Electronic Throttle Wiring Curtis PMC’s electronic throttle, ET-XXX, is wired as shown in Figure 14. It requires a controller with the optional 0–5V throttle input. Curtis electronic Fig.
The faster the vehicle is moving when the motor is shorted out, the more CONTROL WIRING PEDAL KEYSWITCH INTERLOCKS FUSE MICROSWITCH POLARITY PROTECTION DIODE POWER WIRING MAIN FUSE PRECHARGE RESISTOR (250 Ω, 5 W) POTBOX – Basic wiring for use with PM motors. Fig. 15 Curtis PMC 1204/1205 Manual...
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2 × SPDT direction controller B+ FREEWHEEL or DB contactors with a third contactor (SPST). A resistor can be added across the third contactor to provide dynamic braking instead of freewheeling. POWER WIRING CONTROL WIRING Curtis PMC 1204/1205 Manual...
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NOTE amount of braking desired are factors in determining the appropriate dynamic braking resistor; contact Curtis for guidelines.) The N.O. and N.C. contacts of the forward/reverse contactors must be wired as shown in Figure 17 or this scheme will not work.
field connections. F. If you have HPD, check it next. Turn off the keyswitch and direction switch. Apply the throttle, turn the keyswitch on, and then select a Curtis PMC 1204/1205 Manual...
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The vehicle should smoothly brake to a stop and accelerate in reverse. On vehicles that are intended to have plug braking inhibited, verify that the maneuver in “H” produces freewheel coasting. Curtis PMC 1204/1205 Manual...
MAINTENANCE & ADJUSTMENT MAINTENANCE & ADJUSTMENT Curtis 1204/1205 controllers and potboxes require only minimal main- tenance if properly installed. : The controllers are sealed and thus NOTE are not field serviceable. CONTROLLER Maintenance It is recommended that the following two steps be performed occasion- ally.
1. Remove the socket head screw (1/8" Allen) for the adjustment you want to make. 2. Adjust the internal potentiometer using a small insulated screw- driver (available from Curtis). 3. Replace the socket head screw and nylon seal washer. To pre- vent stripping, do not over-tighten. Curtis PMC 1204/1205 Manual...
(with a moist rag) as required. Adjustment Curtis PMC potboxes are factory set and rarely require user attention. To test and adjust, connect an ohmmeter to the potbox wires and use this procedure: 1.
Sluggish Vehicle Behavior Loss of power will be noticeable when the batteries become overly discharged. This is a normal response to low battery voltage. Curtis PMC 1204/1205 controllers are designed to protect against damage caused by low batteries. On 24–36 volt controllers, for example, power to the motor is cut back when the voltage goes below 16 volts.
Hot Controller If the controller gets hot, it does not necessarily indicate a serious problem. Curtis PMC 1204/1205 controllers protect themselves by reducing power to the motor if their internal temperature exceeds 75°C (167°F). Power output will be reduced for as long as the overheat condition remains, and full power will return when the unit cools.
Check current in controller’s M- (motor field) lead while circuit. If current is high but depressing pedal. 4-D, E motor won’t turn, check motor, if NO Current should be high, and motor should turn. wiring & plug diode. 4-F, G, H, I Curtis PMC 1204/1205 Manual...
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If the contactor and KSI terminal are not getting voltage, that’s the problem. Use the voltmeter to find out where it is not getting through. Connect the voltmeter (-) to the controller’s B- terminal and check the following points with the voltmeter (+) lead to trace Curtis PMC 1204/1205 Manual...
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5kΩ pot connected as a two- wire rheostat (0 = full off, 5 kΩ = full on), and also to 5kΩ–0 configura- tions. Some 1204/1205 controllers are sold with other input characteris- tics. If your installation uses a controller with a throttle input other than 0–5kΩ...
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If the voltages are still out of range, the controller is at fault and should be replaced. Curtis PMC 1204/1205 Manual...
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Test the plug diode as follows: 1. Remove power by opening the battery circuit. Take the cable off the controller’s A2 terminal. Curtis PMC 1204/1205 Manual...
2. an ACCELERATOR POTBOX. For controllers with the standard input configuration (a 5 kΩ pot wired as a two-terminal rheostat), a Curtis PMC potbox or any 5 kΩ pot will work fine. Curtis PMC 1204/1205 Manual...
Setup for bench testing. Fig. 20 MAIN POWER KEYSWITCH CONTACTOR SWITCH 12 V POWER SUPPLY 12 V (to match your controller) 12 V POTBOX (to match your controller’s throttle input) TEST LOAD (to match battery voltage) Curtis PMC 1204/1205 Manual...
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The lamps should smoothly increase in brightness to their previous level. F. Finally, remove the controller from the test setup and check its in- ternal plug diode, as described in Troubleshooting Procedure Curtis PMC 1204/1205 Manual...
This feature contributes to smooth, gentle starts. On some 1204/1205 models, the acceleration rate is adjustable via an externally accessible trimpot. See Section 4 for adjustment instructions. The deceleration rate is fixed, and cannot be adjusted.
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Curtis PMC controllers dramatically greater driving range per battery charge. Environmental protection Curtis PMC 1204 and 1205 controllers are housed in rugged anodized aluminum extrusions that provide environmental protection. Controllers must be kept clean and dry, however, to ensure long life.
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The plug current limit is factory set to meet customer requirements. On some 1204/1205 models, the plug current limit is adjustable via an externally accessible trimpot. See Section 4 for adjustment instructions. If plug braking is not desired, the vehicle can be wired so that moving the forward/reverse switch through neutral causes the vehicle to freewheel as long as the accelerator is applied.
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(Appendix C). Reducing the output to the motor allows the battery voltage to recover, and an equilibrium is established in which the battery supplies as much current as it can without falling below the cutback voltage. Curtis PMC 1204/1205 Manual...
PLUG CURRENT CURRENT LIMIT ADJUST ADJUST (internal) Block diagram, Curtis PMC 1204/1205 controllers. Fig. A-1 The controllers consist of a and a POWER SECTION LOGIC SECTION POWER SECTION An array of paralleled power metal oxide semiconductor field effect transistors (MOSFETs) switches pulses of current from the battery to the motor.
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Current limiting is done by sensing the voltage drop across the main power MOSFET switch when it is on. This voltage is compared (current limit comparators) with a current limit reference; when it exceeds the reference, an overcurrent signal acts on the limit integrator to reduce the controller Curtis PMC 1204/1205 Manual...
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When the motor has come to a stop, the plug diode will again become reverse biased and the controller will revert to normal drive operation. Curtis PMC 1204/1205 Manual...
Average current, which determines motor torque, is controlled by the ratio of on/off times. Smooth, stepless control of the power delivered to the motor is achieved with almost no power loss in the control components. Curtis PMC 1204/1205 Manual...
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PWM OPERATING FREQUENCY 15 kHz STANDBY CURRENT less than 20 mA 5 kΩ ±10% (others available) STANDARD THROTTLE INPUT WEIGHT 1204: 1.8 kg (4 lbs) 1205: 2.7 kg (6 lbs) DIMENSIONS 1204: 146mm×170mm×70mm (5.75"×6.75"×2.8") 1205: 146mm×222mm×70mm (5.75"×8.75"×2.8") NOMINAL VOLTAGE UNDER-...
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