- Main features of EPDC type solar power dual output controller
The main features of the EPDC type solar power dual output controller are as follows.
(1) A single-chip microcomputer and special software are used to realize intelligent control.
(2) Accurate discharge control is realized by correcting the discharge rate characteristics of the battery. The discharge termination voltage is the control point corrected by the discharge rate curve, which eliminates the inaccuracy of over-discharge by simple voltage control, and conforms to the inherent characteristics of the battery, that is, different The discharge rates have different termination voltages.
(3) It has the functions of overcharge, overdischarge, short circuit, overload and anti-reverse connection protection.
(4) The series-type PWM charging main circuit is adopted, which reduces the voltage loss of the charging circuit by nearly half compared with the charging circuit using diodes, and the charging efficiency is 3%~6% higher than that of the non-PWM method. The automatic control function of the normal direct charging method and the floating charging method makes the system have a longer service life and has a high-precision temperature compensation circuit.
(5) Using industrial-grade chips, it can operate in cold, high temperature and humid environments. At the same time, the crystal oscillator timing control is used, and the timing control is precise.
(6) Instead of using the potentiometer to adjust the control set point, the Flash memory is used to record each working control point, so that the setting is digitized, and the error of the control point due to the vibration deviation and temperature drift of the potentiometer is eliminated, and the accuracy and reliability are reduced. sexual factor.
(7) LEDs are used to indicate the current battery status in real time, and digital LEDs are used to display and set up. All settings can be completed by one-button operation, which is extremely convenient and intuitive to use.
(8) There are two timing output circuits that can be set independently.
- Specifications of EPDC type solar power dual output controller
The technical indicators of the EPDC type solar power dual output controller are shown in Table 1.
- Main functions of EPDC type solar power dual output controller
EPDC type solar power dual output controller is specially designed for solar DC power supply system and solar LED street light system, it is an intelligent controller with special microprocessor chip. All operations and settings can be completed with a one-button touch switch. It has protection functions such as short circuit, overload, reverse connection, full charge, over-discharge automatic shutdown, recovery, etc. It can display the charging and discharging status, load status and various fault indications of the battery in real time.
The controller samples the parameters related to the battery capacity such as the terminal voltage, discharge current, and ambient temperature of the battery through the microprocessor chip, and calculates it through a special control model to achieve high-precision control of the discharge rate and temperature compensation in line with the battery characteristics. Efficient PWM battery charging mode ensures that the battery works in the best state and effectively prolongs the service life of the battery. It has a variety of working modes and output mode options to meet various application needs. The block diagram of its controller is shown in Figure 1.
- Wiring of EPDC type solar power dual output controller
The EPDC type solar power dual output controller panel is shown in Figure 2. The controller wiring should use multi-strand copper core insulated wires. The length of the wire should be determined before wiring. Under the condition of ensuring the installation position, the length of the connection should be reduced as much as possible to reduce the power loss. The cross-sectional area of the copper wire should be selected according to the current density of 4A/mm2.
When connecting the battery wire, first connect the battery terminal on the controller side, and then connect the battery terminal. When wiring, be careful not to connect the positive and negative poles in reverse. If the connection is correct, the battery indicator on the controller panel is on, and the controller can be checked by pressing the button. Otherwise, you need to check whether the wiring is correct.
When connecting the solar cell wires, first connect the solar cell module terminal on the controller side, and then connect the solar cell terminal. When wiring, be careful not to reverse the positive and negative poles. If there is sunlight, the charging indicator on the controller panel should be on. Otherwise, check whether the wiring is correct. Finally, connect the connection of the load to the load output terminal on the controller. When wiring, be careful not to reverse the positive and negative poles.
When the system connection is normal and the sun shines on the solar cell, the charging green indicator on the controller panel is always on, indicating that the charging circuit of the system is normal; when the charging green indicator flashes rapidly, it means that the system is over-voltage. The battery charging process uses the PWM method. If over-discharge protection occurs, when resuming charging, the controller must first increase the charging voltage to the set value and keep it for 10 minutes, and then drop it to the direct charging voltage and keep it for 30 minutes to activate the battery. Avoid sulfide crystallization of the battery, and finally drop to the float voltage and maintain the float voltage. If there is no over-discharge, it will not enter the mode of increasing the charging voltage to prevent the battery from losing water. These automatic control processes will enable the battery to achieve the best charging effect and ensure or prolong its service life.
When the battery voltage is in the normal range, the status indicator light is green and long on: after the battery is fully charged, the status indicator light is green and slow; when the battery voltage drops to undervoltage, the status indicator turns orange; when the battery voltage continues to drop to the overdischarge voltage , the status indicator turns red, and the controller will automatically turn off the output at this time. When the battery voltage returns to the normal working range, the output switch circuit will be automatically enabled to conduct, and the status indicator will turn green.
When the load is turned on, the load indicator on the controller panel will be on for a long time. If the load current exceeds 1.25 times the rated current of the controller for 60s, or when the load current exceeds 1.5 times the rated current of the controller for 5s, the indicator light will flash red slowly, indicating overload, and the controller will turn off the output. When there is a short circuit fault on the load or the load side, the controller will immediately turn off the output and the load indicator will flash quickly. When the above phenomenon occurs, you should carefully check the load connection. After disconnecting the faulty load, press the button once, and it will resume normal work after 30s, or wait until the next day to work normally.
- Setting of EPDC type solar power dual output controller
(1) Setting method. Press the switch setting button for 5s, the LED of the number displayed by the mode (MODE) flashes, release the button, and each time the button is pressed to convert a number until the number displayed by the LED is the same as the number of the selected mode (see Table 2 for mode selection). , Table 3), that is, stop pressing the button, and wait until the LED number does not flash to complete the setting. After 6 or 6. and 7 or 7. are used, the two outputs are controlled synchronously, and it is necessary to reset 1~5 or 1.~5. to enter the independent control of the two outputs. Each time the button is pressed, the digital LED lights up, and the set value can be observed. The displayed value at 6 or 6. and 7 or 7. will not change from on to off. In other cases, set 1~5 or 1.~5. . The first 3s indicate the setting of the first load, and the last 3s indicate the setting of the second load.
(2) Pure light control method. When there is no sunlight, the light intensity drops to the starting point, the controller delays for 10 minutes to confirm the start signal, then turns on the load, and the load starts to work; when there is sunlight, the light intensity rises to the starting point, and the controller delays for 10 minutes to confirm that the output is turned off After the signal, turn off the output and the load stops working.
(3) Light control + delay mode. The startup process is the same as before. When the load works for the set time, the load will be turned off. The time setting is shown in Table 2 and Table 3.
(4) Universal photovoltaic controller mode. This method only cancels the light control function, time control function, output delay and related functions, and retains all other functions as a general general photovoltaic controller.
(5) System debugging method. The use method is the same as the pure light control mode, only the 10min delay of judging the light signal control output is canceled, and all other functions are retained. When there is no light signal, the load is turned on, and when there is a light signal, the load is turned off, which can easily check the correctness of the system installation. When the LED digital tube displays the mode setting value, if the displayed number does not have a decimal point, that is, “0”~”5″, it corresponds to the setting of load 1. If the number with decimal point is “0.”~”5.”, it corresponds to the setting of load 2. 6 or 6. Both set the general controller manual switch mode; 7 or 7. Both set the test mode of pure light control. The controller working mode settings are shown in Table 2 and Table 3.
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