Knowledge Base

User Manual: DVOC Top Light DVTL-002x

This manual explains the setup and operation of the custom red, blue, green (RGB) and white top lighting in the DVOC-0040 / DVOC-0041.

Connecting the Components

The setup consists of a DanioVision Observation Chamber with built-in custom top light, a desktop power supply, a TTL-to-28V interface, and cabling. With this setup, two of the LED colors, or the white light, can be switched on and off from EthoVision. The TTL-to-28V interfaces enable switching the power from the desktop power supply.

If you would like to use all three colors (R-G-B) within one experiment, you will need a second TTL-to-28V interface.

The LED power cable (coming from the back of the DVOC) has four connectors, one for each LED color. The connectors belonging to the appropriate colors should be connected to the TTL-to-28V interface on outputs 1 and 2. The TTL network cable (green) should be connected between the TTL-to-28V interface and port 1 on the DVOC. A main power cable connects the desktop power supply to the input of the TTL-to-28V interface.

Operating the Power Supply

Supply version: PeakTech 6225A.

Prior to connection to a mains outlet, check that the mains voltage corresponds with the voltage setting of the supply.

On the power supply, the voltage can be set to determine the amount of light that the LEDs emit. The voltage must not exceed the maximum voltage for each LED color:

• Red, Green, and Blue LEDs: maximum 24V
• White LEDs: maximum 18V

Note that higher voltages may damage the LEDs.

To operate the power supply:

1. Power up using the power switch on the back.
2. Adjust the voltage by turning the Voltage knob. Press the knob to switch between coarse and fine adjustment.
3. Read the actual output voltage from the display.
4. Set the Current knob to its maximum level (turn fully clockwise). This knob sets a current-limiting value and is not needed for this application. If not set correctly, the supply may enter Constant Current (CC) mode and limit the output voltage.
5. After setting the desired values, switch the actual voltage output on using pushbutton 8 on the front.

It is good practice to set your desired voltage before connecting the main LED power cable to the supply. Refer to the supply manual for further details.

Changing Between Red, Green, and Blue

To change between colors, unplug the current connector of the LED power cable from the TTL-to-28V interface and plug in the correct one. Each connector is labelled with its corresponding color.

Changing Between Color and White Light

To switch between RGB and white light, the unit must be turned so that the correct LEDs face downward toward the well plate. The RGB LEDs and white LEDs are mounted on opposite sides of the same aluminum base plate, identified by the labels "White" and "RGB".

1. Cover the lens bracket with protective material.
2. Loosen both the left and right round black knobs to allow the unit to slide down a few centimeters, just below the camera.
3. Pull the unit out and turn it upside down so that the preferred LEDs face downward. Be careful not to twist the cable at the back. You may temporarily unplug both connectors to prevent twisting.
4. Insert the unit and slide it back up.
5. Tighten both round knobs.

Settings in EthoVision XT for Switching Light On/Off

Start EthoVision XT and create a new experiment using a template via File > New from Template. During the guided setup, choose Live Tracking, Zebrafish Larvae, and DanioVision with the type of well plate you are using.

Configuring Trial Control Hardware

1. Choose Setup > Experiment Settings.
2. Under Trial Control Hardware, select Use of Trial Control Hardware.
3. Choose the options as shown in the reference figure and select the TTL port that you connected.
4. You can rename the Device ID to something descriptive, such as "Ceiling Light".

Configuring Arena Hardware Mapping

1. Choose Setup > Arena Settings.
2. After calibrating and drawing the arenas, click Arena Hardware Mapping.
3. Click Add Device and follow the on-screen instructions. You can rename the device to something like "Ceiling Light".
4. Under A1, select the device, then click OK.

Testing the Light

To test the light, select Output 1 High or Output 2 High from the dropdown menu and click the Test button. To turn the outputs off, select Output 1 Low or Output 2 Low.

Programming the Light During Trials in EthoVision XT

Choose Setup > Trial Control Settings.

The following is an example protocol: after 1 minute during the trial, switch the light on, then after 10 seconds switch it off.

• Use Conditions > Time to create time conditions (e.g., Wait 1 minute, Wait 10 seconds).
• Use Actions > Custom Hardware to define commands (switch on/off) for output 1 and output 2.
• Connect all boxes with the start-stop procedure.
• Use the Subrule function to create repeating routines (e.g., switch on-off-on).

Also adjust the Detection Settings via Setup > Detection Settings before running trials.

For more information, refer to the following resources:

• The DanioVision DVOC-0040 User Manual
• The Trial and Hardware Control – EthoVision XT 11.5 Reference Manual
  • Chapter 5: Subrules
  • Chapter 7: Controlling Hardware Devices

Tips

• The LEDs get hot during operation. Allow the ceiling light to cool down before touching it.
• Do not exceed the maximum specified voltage for each color, as doing so may damage the LEDs.

Specifications

White Light

• Illuminance: >30,000 lux at 25 cm distance (well plate)
• Luminous flux: 1,584 lm
• Color temperature: 4,000K
• Array of 408 LEDs
• Maximum voltage: 18V

Red Light

• Luminous flux: 192 lm
• Wavelength: 623 nm
• Array of 252 RGB LEDs
• Maximum voltage: 24V

Green Light

• Luminous flux: 384 lm
• Wavelength: 525 nm
• Array of 252 RGB LEDs
• Maximum voltage: 24V

Blue Light

• Luminous flux: 240 lm
• Wavelength: 470 nm
• Array of 252 RGB LEDs
• Maximum voltage: 24V

Unit Dimensions

• 270 x 220 x 30 mm

Source: TopLight User Manual, Noldus Information Technology