Solar Panel Assembly

This page contains the solar panel assembly procedure for the Iris satellite. To verify this procedure, a test assembly was done in the cleanroom.

Assembly Procedure Test In The Cleanroom

Here's a step by step report of the assembly test that was done in the cleanroom of Magellan Aerospace on Friday, September 24, 2021.

The handling of the cells and panels were done in an ESD safe workspace.

1- Unboxing the solar cells. The cells were bought from AZUR SPACE company.

2- Unbox the solar panel PCBs manufactured by PCB Way. In this test one of the extra UMS-0439 PCBs were used. The PCBs were cleaned after unboxing using IPA and Keen wipes.

3- Mixing silver epoxy: measure 0.5 gm of each part of the epoxy and pour into a separate container and mix it until a uniform paste is made.

4- Applying a uniform coat of the epoxy on the PCB using a spatula and a swab. The excess epoxy was cleaned using keen wipes and cotton swabs and IPA before mounting the solar cell.

5- Mounting the solar cell on the designated area covered with epoxy. Aligning with the silkscreen lines to ensure proper installation.

6- Transferring the panel to the oven to cure the epoxy inside an ESD bag and an ESD safe box.

7- Curing the epoxy (The silver epoxy datasheet recommends a cure time of 1 hour at a temperature of 150 Celsius but the oven was only calibrated to 120 Celsius. Since this was also accepted in the datasheet we cured the epoxy for 1 hour at 120 Celsius)

8- Setting up the soldering station and soldering the solder tabs. (Temperature of 300 Celsius resulted in a poor solder joint so a higher temperature of 350 Celsius was used for test)

9- The open circuit voltage and the short circuit current of the cell was measured after installation. Voc was about 2 Volts which is close to the specifications of the cells. The measured Isc was about 1 mA which is much lower than what was stated in the datasheet. (Insufficient light in the cleanroom or the silver epoxy not being fully cured could be the reason for this poor performance)