Automatic Sun Tracking

Dual Axis Radiation Control Module

Page last updated:  25/4/23

Please Note: This $150 Hobby type Dual Axis-solar Tracking (DAT) Control Module does Not use Automotive Relays, it is said these relays will Fail first, but we have NOT had any Relays failures after over 3 year now, so we consider they are great Value for the money.

However, if the Module or any of it's components happen to Fail, it's Cheap, Easy & Safe to Replace the whole Module, as the Module Voltage is only 24V DC.

Quick Set-up for those that don't read instructions;

1. V1: 0.01 =% Sun Accuracy, the higher the less accurate the panels will be to the Suns position or the Brightest area of the Sky.
2. V3: 1.00 Sun Threshold: Voltage Settings, try between 0.50~2.00V, the lower the value the more the tracker will Chases the brightest part of the Sky, if set at 1.00V the G= reading value on the Control panel will be approx. 4 volts, before going into the T13 Low Sun Countdown, awaiting for the sun to re-appear, if Not the racking will then go into Stow/Park position, as below.
3. V2: 0.25 Wind Speed Threshold (voltage), as every location will have different wind conditions, Set V2 initially to 0.10 (V2=Volts) to Test using a Leif Blower into the Cups, if you think it is set to Low, adjust to a higher setting, and Test using a Leif blower directed into the Cups.
   NB: The "F=" Reading is Voltage Generated, and must be F=0.00 when Not rotating, or it is incorrectly wired.
4. TX: 800 =800 seconds Rotation East~West, this needs to be Timed as every platform will be different, as the larger the Slew bearing the longer it usually take, commonly between 360~550 seconds.
5. TY: 400 =400 seconds Tilt North~South, or say 180 seconds (2minutes), if you don't want the Racking to Move as often.
   
6. T7: 600 The Wind Speed Safety Stow Time, the racking will stay in the South/Flat position, if the V2: value is set to low, the racking will keep wasting time going into stow position Unnecessary.
7. T13: Low Sun Waiting: We recommend setting this to 7'200 seconds (2 hours), then if the Sun Re-appears during this time, it will keep tracking the Sun or the brightest part of the Sky, if Not the Racking will Automatically enter into the Stow Position.  You can Program the Stow position so the racking Faces Any position, but best if the Racking is facing East, as it will wake-up in the Morning & simply Tilt to the Rising Sun.
8. Recommended Stow Position: (Southern Hemisphere) T9:800 (East), T10:000 (West), T11:000 (North) & T12:400 (South-Flat) are used to program the Stow/Park Position, the T12 time sets the Racking track South, the Flat position in Australia, ready for the first rays of Sunrise.

NB: If you are use 12V into the DART Controller the Rotation in all Directions will be Slower, so Time it yourself !

Please note: If Hi-Wind occur overnight the V2 setting will trigger the racking to Stow Flat using the T6 Time setting, the T6 time needs to be set to the Time it takes to travel from Full Tilt to the Flat position.

If the T13 countdown is set to low & finishes during bad/overcast weather, it will automatically track back to the Stow position settings, so setting a higher T13 time will delay the Stowing to see if the Sun reappears before Sun-Set or during bad weather & cloud cover.

We suggest starting with T9:400 (East), T10:001 (West), T11:001 (North), T12:240 (South), commonly if the setting are to low at Sunset the Racking will be facing in a slightly different position each day, so the time entered into T9 & T12 will affect the Stowed position, not really a problem as the racking will start tracking to the Sun at daybreak, the V3 setting controls the Wake-up voltage.

------ End of Quick Set-up ------

System Description:

This controller tracks the East to West & North to South movements of the sun in real time, and has the functions of stowing Flat in High Wind or a cloudy day, and at night if required, the Racking can be left at full Tilt facing East awaiting for the Rising Sun, if High Winds pick-up at Night the controller will Automatically Stow Racking Flat programmed by T6 setting.

The infrared wireless controller can be used to adjust various parameters freely, the LCD screen displays the parameters being changed, however it is more accurate to use the control panel.

The requirements are:

The DAT unit must be driven by two brushed DC motors, and where Slew Bearing(s) are used, limit switches should be installed to stop over rotation.  The two DAT motors need the same voltage, and be 12~24V. The total current should not to exceed 6A. When the current is greater 6A, another intermediate relay control box needs to be added.

The DAT Controller is divided into Four parts:

1. Testing head parts

The Light detection head adopts a four-quadrant photo-diode detection method, which blocks direct light by an umbrella type cover to produce different sunlight radiation voltage values in four directions. When the angle to the sun is less than about 10 degrees, the inner ring photo-diode in the inner hole captures the sunlight and output signals, this method greatly improves the tracking accuracy, four signals are transmitted to the motherboard through a 5-core cable. The installation method is M4 bolt fixing (left and right spacing 44MM), all parts are made with 3D printing technology and professional crystal epoxy board production process, and the back welding line is covered with waterproof silicone to prevent normal rain.

2. Control box.

The control box is not a waterproof shell and needs a weatherproof Housing, and has a circuit composed of MCU, LCD and other components. The five-core signal introduced by the detection head (Light sensor) is judged by the built-in program of the circuit. According to the corresponding situation, the motors are engaged to track the Sun. Its interfaces are the five-core signal of the Light sensor, the signal of wind speed sensor, wireless remote control signal, power input and the output of east-west axis motor. North-South axis motor output, etc.

3. Remote control

The 6-key infrared remote controllers can achieve a variety of operation functions. Besides the manual operation function, it also has the function of adjusting various control parameters. The distance between the remote controller and the control box is 8mt, and uses two AAA batteries.  It is more accurate to use the instrument panel for precise adjustments.

4. Wind speed sensor.

The function of the wind speed sensor is to detect the live wind speed. When the wind speed triggers a value greater than the set V2 value, the controller will stow the racking flat to minimize the damage of the racking. The wind speed sensor has a three-cup rotating module. When the wind from any direction is high enough, it will rotate and register a Voltage shown as the F=0.00 reading, the faster it rotates it will generating different voltage signals. The control box makes wind judgment based on the wind sensor voltage signal.

The basic principle and installation method of the DAT controller are:

The controller uses a Light sensor detection head, in a closed-loop control mode that detects where the Sun is or the brightest part of the Sky (Radiation) is in real time. The controller analyses the Racking position and drives the corresponding axis motor to move. As the Racking moves so does the Light sensor head, and as the voltage value changes in real time, the motors moves the Racking until it is aligned perpendicular (directly at) to the Sun, then the controller stops movement.

The main logic of the procedure:

After power-on, check the sunshine intensity. If the sunshine intensity is enough, the racking will start aiming at the sun. If the sunshine intensity is insufficient, it will delay for any movement and first enter into T13 Sun Recovery, period then into T8 Low Sun Waiting period, and there after the Racking will move into the Parked Position (Programmed by setting T9/T10/T11/T12 parameters).

When the wind speed is detected to exceed a certain value, the Racking performs the specified action. (Programmed by setting T3/4/5/6.)

When the Sun runs in the northern hemisphere for a few days in summer, the device can start the required action at noon so that it can continue tracking in the afternoon. (This action can be performed by setting T14/15.)

When the manual function starts, the racking unconditionally accepts manual control.

Each function parameter can be set by itself. Human-computer interaction is completed by remote control and LCD screen.

Installation and debugging method:

Firstly, the light detection head should be installed on the upper South side of the racking, and the rotational range of the East and West axes of the racking should be set for Summer Solstice, that is WEST Stop Position is 120° from North towards West, and EAST Stop Position is 120° from North towards East.

The Tilt angle North Tracking should tilt towards Vertical as your racking allows, approx. 60°, the Southern backwards Tilt will end up Horizontal/Flat.

This DAT Controller uses Normally Open (NO) Stop sensors, these should be fitted to all Slew Bearings to stop Damage from over rotation, that will either Damage the Motors &/OR Racking, most Liner actuators have built-in Limit switches, however it is STILL better to install the same Stop Sensors on the Tilt Axis as a Safe-guard.

When the Light detection head is fixed on the platform, attention should be taken so that the East direction corresponding to the East direction when the Racking is Flat & Facing North direction (flat and centred).

Put the correct DC voltage into the main DAT control box.

(Infrared remote control can turn on or off the back-light by pressing QUIT key for more than 5 seconds)

No matter what state the controller is in, press the remote control SET Keyboard once, that is, enter the manual control state. Press the corresponding remote control button at this time→/←/↓/↑Key, the controller will go to east/west/south/north Move in direction and display on the screen E/W/S/N. If the direction of movement does not correspond to the description in the manual, the corresponding wiring shall be changed until it is consistent with the description in the manual.

Press the remote control QUIT key, it exits exits the manual state and the controller Saves the entries, and enters the automatic state. At this time, there are several possibilities as follows:

Situation-1) If the sunlight value detected at any direction of the detection head is higher than that detected at this time V3, the control considers that it is sunny and enter the platform tracking state. The controller drives the racking to move to the east-west axis or the north-south axis aligns first, the axis stops and enters the delayed waiting state. The east-west axis and the north-south axis have a delayed waiting time which can be set freely. TX is the waiting time for the next alignment after the east-west axis aligns. For the North-South axis. The time can be set according to actual needs. The advantage of this delay setup is that it can save energy to avoid frequent actions (when there is a gap between platforms, poor locking may cause frequent actions), and it can ignore some shadow interference (such as the shadow of wires, the shadow of birds flying, etc.).

Situation-2) When the voltage value detected in any direction of the detection head can not be higher than V3 When it is rainy or night, the controller considers that the ambient light has no power generation value. At this time, the controller standby and timing.T8Time countdown delays waiting.

T8 is the countdown of time, if the ambient light exceeds V3 Value and lasts longer than T13, then immediately enter normal tracking if ambient light continues to fall below V3 after the T8 delay is completed, the controller will perform the specified actions of the platform. After the execution of the action of Levelling, it enters the weak waiting state of sunshine. If the sunshine appears, it delays T13 time to enter the automatic tracking.

Situation-3) When the controller detects that the wind speed exceeds V2 value, the controller considers that the current wind speed may damage the platform, and it is necessary to put the platform in the Flat position immediately to reduce the damage by the wind. At this time, the controller performs the specified action of T3, T4, T5 & T6 Times you set, commonly it is best to simply sent the Racking in the Flat Position.

The T7 is the lock-in holding time, in which case the wind speed recovers below V2 Value, then when the T7  time is over, it exits to the previous state, if the wind speed is still higher than the V2 Value, the lock state is maintained until the V2 is lower than the setting, Only then does the countdown begin and exit after the countdown ends.

Parametric and Symbolic Descriptions:

AT: Automatic tracking state, in which the Racking automatically tracks the sun.

TX: When the East and West axes are aligned, the Racking will not move during the waiting period.

TY: When the north and South axes are aligned, the Racking will not move during the waiting period.

E: East W: West S: South N: North (Indicator moves in the corresponding direction)

FS: Shows the Wind Speed has exceeded the V2 value, and is levelling off to reduce possible damage.

F: Is the Live, Real-time Wind Speed shown in units of Volts.

G: The total voltage of light sensor measured in four directions, is referred to the current total sunshine intensity.

MT: Manual operation state, the north/south/west/eastern buttons inc. remote control, Manually move the tracker.

SL: Weak sunshine means that the current controller thinks the sunshine is weak and will enter a dormant state to wait for sunshine to appear again.

SL WAIT: Entering the Weak Sun Hibernation state, usually late evening/night mode.

T3: The time value the racking moves Eastward after exceeding the set wind speed limit.

T4: When performing a specified action of exceeding the wind speed limit Undertake T3 After time, the time value of driving device to the West

T5: The time in Seconds the Racking Tilts northward after Wind speed limit is exceeded.

T6: When performing a specified action of exceeding the wind speed limit Undertake T5 After time, the time value of the driving device heading south

T7: Is the self-locking time triggered when wind speed signal voltage of the V2 voltage, shown in the F= reading, the V2 is designed to prevent the is programmed effect of wind speed from being intermittent and causing frequent action of the device Tracking, in the self-locking time, if the wind speed re-exceeds the value, then the time immediately re-timed, so that the device will not operate frequently.

T8: The countdown time in seconds after weak sunlight is triggered, before T9, T10, T11 & T12 are triggered.

T9: Time value of the Racking rotating Eastward when performing weak sunlight/Park position.

T10: Implement Weak sunlight the Westerly rotation time, Undertake After T9 countdown time, it rotating to the West

T11: Implement Weak sunlight Designated action time, is the time value of the Racking tilting Northward.

T12: Implement Weak sunlight Designated action time Undertake T11 After time, the time value tilting Southward (flat).

T13: The countdown delay time awaiting for Recovery of Sunlight (recommended: 3'600 seconds =1 hour), before T8 countdown occurrence, before going into hibernation/parking in the stow position, commonly awaiting for the next sunrise.

V1: Tracking Accuracy Settings, which set the Tracking Accuracy Interval Voltage Value, that is, East/West and North/South, How much is the difference between the voltage values of silicon wafers detected in North, when the controller considers it necessary to move the device or aim at the sun, the smaller the value, the higher the accuracy, and vice versa, the lower the accuracy, which needs to be set according to the characteristics of the platform.

V2: When the output voltage of the wind speed sensor is higher than the threshold value set by the controller, the controller considers that it is necessary to stow/level the racking immediately to protect the platform.

V3: When the combined voltage value of light sensor in the four directions of detection is no higher than the V3 value, the controller considers that the current sunshine is weak, there is no power generation value, it cancels tracking and triggers the T8 countdown function.  If the sunshine hasn't been restored after the countdown time, the perform actions into the Stow position.

X0: Because the voltage of the Light Sensor head consistently changes during the day, the controller reads the strongest light direction, and moves device can more accurately align with the sun. The method of setting the parameters is explained in detail later.

Y0: The principle of on-line correction of north-south axis angle is the same as that of north-south axis angle X0.

Method of setting parameters:

How to enter the setting state: Press and hold the remote control in any state5The bond lasts more than four seconds. This page shows the real-time voltage values of the silicon wafers in the first four directions. In debugging and other situations, the output voltage signals of the azimuth detection head can be viewed in real time on this page.

here↓/↑Press The key can turn the page.→/←Key to add or subtract parameter settings.→/←Keyboard press once is a single value addition and subtraction, hold still, is fast addition and subtraction.

Press↓/↑The key can be looped in the above parameter setting state, press→/←Key can add or subtract parameters, after setting, press QUIT key, save the exit.

X0/Y0 The method of setting parameters is as follows:

On a sunny day (try not to be sunny in the morning or evening or at noon at the most time, in the morning or afternoon is more appropriate), first enter the manual operation state, with the remote control manual control platform aiming at the sun, confirm the platform aligns completely with the sun, Then press down. SET Keyboard more than 5 seconds, that is, enter the setting surface, enter the first and second pages after setting, appear the value of East-West and North-South voltage of the detection head, and show the corresponding reference of correction cardinality below, remember the corresponding value of X0 and Y0, and then turn pages into the setting pages of X0 and Y0 with remote control, modify the corresponding parameters to the corresponding value, save and exit.

All of the above states are shown on LCD screen, including all kinds of time and states, which are displayed in numbers or letters.

Description of each component of the control board:

1. Buzzer        2. Remote control receiver         3. LCD screen    

4. Detection head connection terminal   5. Wind speed sensor terminal   

6. Limit terminal interface     7. Fuse (7.5A)       8. Power input (12-24V DC, left Positive right negative)) 

9. East-west axis motor output     10. North-south axis motor output             11. Motor output indicator

Auxiliary Tips Reference:

1: When the back-light of LCD display is not needed, it can switched off to save power. The contrast of LCD screen should not be disturbed, so as to avoid the maladjustment of the contrast to the lowest level, which is supposed to be a display failure.

2: TX The Rotation values is generally set around 180 seconds (3 minutes) before moving, because the racking needs less Tilt after Sunrise, through to Sunset when it will be at maximum tilt to generate the last rays of sun, before Stowing.

3: TY The Tilt value can be set to 600 seconds (10minutes) according to your latitude, as the tilt moves less distance than the rotation over the length of the day.

4: T3/4/5/6 According to the moving speed of the platform, conceive what attitude the platform should move to resist the wind in the case of wind, and then set the corresponding time parameters. Generally, it is to perform levelling, that is, to drive northward to the end..

5: T7 Is the time delay of self-locking after Levelling in the wind. The time value can be set a little longer to avoid frequent action of intermittent wind-driven devices.600About seconds is appropriate.

6: T8 It is the delay time of weak sunshine, which is used to calculate the duration of weak sunshine. This value should be set a little longer to avoid frequent platform movements caused by short rains and clouds.1200More than seconds is appropriate.

7. T9/10/11/12 is the time for executing the specified action when the Sun is Weak. According to the moving speed of the Racking, it may take 480seconde (8 minutes) for the Racking to move from furthest West to East position. North-South axis. that will do That is to say, to go east for a certain time to determine that the time can end, and then to go west for half the time of the whole journey. The north-south proposal is to levelling because the night is longer, levelling is conducive to shelter from the wind, and if it is daytime, in case the sun is temporarily lost, levelling is also conducive to the capture of the sun when it appears again.

8: V1 Tracking accuracy settings, generally Set up between 0.00-0.15. According to the accuracy and tracking effect of the platform, 0.01 is recommended.

9: V2 Is the wind speed start-up voltage. The default configuration of the wind speed sensor is as follows0.1VSettings can be adjusted by users themselves. If other wind speed sensors are used, voltage type wind speed sensors must be used. The parameters should be set by themselves according to their specifications. The method of fuzzy setting is to observe how much F = is when you feel that the wind in the environment at that time may damage the platform. On this basis, you can set it a little lower. For example, if F = 0.30V at that time, it would be reasonable to set the threshold V2 to 0.25.

10: V3 Is the weak threshold of sunlight, recommended between 1.5V~2.25V is a reasonable Setting, the lower the Volt setting the more the Racking will chase the brightest area of the sky.

11: X0/Y0 Settings (E/W & N/S) depend on the light detection head.

12: Rotation & Tilt Stop sensors should be fitted to Stop Damage from Over Rotation of the Racking, Limit Switches are purchased separately.

Basic parameters of the controller:

• Power supply voltage: 8-28V
• Standby current: less than 0.02A
• Maximum control current: less than 6A
• Tracking accuracy: highest 1 degree
• Wind speed start-up protection function: Programmable.
• Anti-power reverse connection protection function.
• Over-current protection.
• Detection head life: 10years.
• Remote control distance: approx. 8 meters.
• Working temperature: -40~60° Centigrade.

In addition, if you have higher requirements for the controller, such as the need for external computer communication, temperature detection and control function, motor current detection and control function, LCD display, and higher accuracy requirements, or the sun attitude angle calculation and tracking, gyroscope induction platform azimuth control, tracking control for focusing purposes, that requires additional equipment you will need to source.

Any questions please contact us, thanks.