Core tips£ºHua Liya TDL-2002ZA of electric motorcycle key switch very poor contact, sometimes loss of
This car a few at first by turning the key to return to normal work. Now try turning the key after the power failure, the car cannot return to normal (though there is no voltage the voltage indication table indicates, but rotational speed control handles, wheel motors can not turn).
Use alcohol to clean the key switch, making it reliable contacts, then test fault remains. Open the controller observed PCB, know the yellow line and the blue line of wire harness 1 the polarity of each wheel motor; the Orange wires of the wire harness 2. 48V battery anode, picked up on the key switch to the red line on the 48v power supply, black earth (level is negative); wiring harness 3-5V power source of speed control handles the red line, the blue line speed control voltage outputs of the handle, black ground; brown wires of the wire harness 4 brake control output voltages. 48v power supply through the relay contacts on the circuit board power to the hub motor.
Close the key switch, measuring wire harness 2 red 48V voltage (fully charged to 52V). Rotational speed control handles, measuring wire harness blue line 3 output voltage 1.6V (low) ~4.3V (high speed) vary continuously. Holding brakes, measuring wire harness 4 Brown line voltage 9V (brake) or OV (without brake). However, the wire harness 1 yellow line and the blue line voltage is always between OV, namely wheel motor supply voltages, but also for the wheel motors power supply relay contacts are not closed. Relay coil end 48V power supply controlled by key switch, 660 ω resistor at one end by driver transistor T3 c, T3 b hopelessly high. Due to the orange wire of the wire harness 2 (48V battery positive) fuse, such as motor circuit short circuit over current, fuse fuse protection circuit and battery. So, try T3 c very grounded, forcing for the relay coil is energized, make it a hub motor-powered contact closure, turn speed control handles, wire harness 1 yellow line and the blue line to ground voltage is 52V, hub motor is always positive and negative voltage OV, hub motor still does not rotate.
To get at the circuit in order to repair, the controller circuit is measured. As shown in the figure. This circuit using pulse width modulation controller TL494CN (used as a motor speed control).
48V power supply controlled by a key switch (batteries 52V) after VF2, VF1, voltage regulators TL494cN and LM358P 15V power supply.
Internal voltage reference can be obtained from TL494CN (14) the REFOUT port 5V output (± 5%) reference voltage (14) feet except for the error amplifier output voltage provides a reference voltage, but also power the speed controller circuit and heavy load voltage will be lower, so the earth terminal (7) foot by 20 ω resistor R28 grounded. (13) OUTPUTCONTROLIC output control of the foot, the foot base voltage of 5V, the TL494CN of QT1 and QT2-parallel push-pull output; the feet grounded, QT2 and QTl for single-ended output, the circuit (13) feet grounded. (4) foot DEAD-TIMECONTROL dead-time control in this circuit grounding. (5) foot and (6) foot external capacitance CT, resistor RT determines the size of the internal oscillator circuit of the oscillation frequency.