Start Date:
June, 2024
End Date:
September, 2024
Part Name:
UMS-0587-EM
Application:
EPS Electronics Board
Quantity:
3
Item
P1
P2
Property Item
Visual Inspection
Measurement of physical characteristics
Result
PASS
PASS
Details
Item
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
Test Item
Ideal diodes and DET switches test
Battery interface and protection
Analog 100 second timer test
Load switch (CCLSM) test
Temperature sensors test
Watchdog timer test
Bus inhibit test
Ground inhibit test
Inter-subsystem communication tests
RBF logic test
Test Result
PASS
PASS
PASS
PASS
PASS
PASS
PASS
PASS
PASS
PASS
Details
No.
1
S/N
UMS-0587-EM
Pack Group
UMS-0587
Start Date:
June 24, 2024
End Date:
September 31, 2024
Part Name:
Application:
Quantity:
Item
P1
Test Item
Visual Inspection
Test Specification
Inspect the PWBs for any deformation, discontinuity in visible traces, and cracks on the boards. For PWAs, look for missing components, misplaced components and cracked/ broken/ bent components.
Judge Criteria
There shall be no such defects or flaws stated in the test specifications in any of the received boards.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
June 24, 2024 to June 25, 2024
EPS boards (3 PWAs)
None
Use the ESD safe mat for all these inspections
None
Raw Data:
Board Assembly:
UMS-0587-EM
Item
P2
Test Item
Measurement of physical characteristics
Test Specification
The Width and the height of the board must be measured and recorded. For the PWBs, the thickness of the boards must be recorded and for PWAs, as well as board thickness, the height of the highest component must be measured and recorded.
The mass of all the boards must be measured and recorded.
Judge Criteria
Width: 90±0.25 mm
Height: 90±0.25 mm
Thickness: 1.52±0.25 mm
Highest component:
XX±0.1 mm
Mass: XX±1 gr
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
June 27, 2024 to June 27, 2024
EPS boards (3 PWAs)
None
Use the ESD safe mat for all these inspections
None
Raw Data:
Board Assembly:
UMS-0587-EM
Item
T1
Test Item
Test the functionality of Ideal diodes and DET switches and the current sensors.
Test Specification
Follow the instructions provided below for all 7 inputs of the solar arrays to verify their functionality.
Judge Criteria
For all 7 inputs the following shall be verified:
*Ideal diodes prevent flow of current when Vin<±0.05V
*Current sensors accuracy =±50 mA
*When EN is off: current<10mA
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
July 10, 2024 to July 10, 2024
EPS board assemblies, variable power supply, fixed 5V power supply, electronic load, multimeter, EM battery pack
None
Use the ESD safe mat for all these inspections
None
Raw Data:
Board Assembly:
UMS-0587-EM
Detailed Instructions:
Connect the battery pack to the board. Power up the board using Board power-up procedure
Find the solar panel inputs on the left side of the board*. The connectors numbered J1-J7 are for the positive side and J8-J14 are for negative side. We will refer to these as ‘power input pins’
Run the power controller script that toggles the solar array inputs on/off and read the current measurement feedback in the code. Write down the results.
Follow these steps to verify the function of ‘Ideal diodes’
Measure the battery pack voltage. We’ll call this Vbatt
Set the power supply voltage to 6.4 V (we’ll call this Vsupply) and set the current limit to 0.2 A and turn off the power supply
Connect the power supply to the power input pins
Turn on the EN pin through the script.
Turn on the power supply
Read the current measurement from the test script.
Change the power supply voltage in the range of (5V~7.2V). Read the current value. This value shall represent 0A for Vsupply< Vbatt and a positive current for Vsupply> Vbatt. The conversion factor is 1V/A.
Follow these steps to verify the function of ‘DET switches’
Measure the battery pack voltage. We’ll call this Vbatt
Set the power supply voltage to 7.2 V (we’ll call this Vsupply) and set the current limit to 0.5 A and turn off the power supply
Connect the power supply to the power input pins
Turn off the EN pin using the script.
Read the current measurement through the script.
Turn on the power supply
Read the current value. No current shall pass at this moment
Turn on the EN pin using the script.
Read the current value. A positive current shall pass at this moment. The conversion factor is 1V/A
Follow these steps to verify the function of ‘Current sensors’
Measure the battery pack voltage. We’ll call this Vbatt
Set the power supply voltage to 7.2 V (we’ll call this Vsupply) and set the current limit to 0.5 A and turn off the power supply
Connect the power supply to the power input pins
Turn on the EN pin using the script.
Read the measured current through the script.
Turn on the power supply
Read the current value and compare it to the value shown of the power supply’s ammeter. The two values shall agree with an error less than 5%. The conversion factor is 1V/A.
*
Item
T2
Test Item
Test the functionality of the coulomb counter and the battery protection circuits
Test Specification
This test is to verify the safe charge and discharging of the battery pack as well as testing the coulomb counter’s ability to interface and send/receive data via the (pins)
Judge Criteria
Battery voltage shall not exceed 7.3V in charging and shall be kept higher than 4V in discharging.
The coulomb counter values shall agree with the battery specifications
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
July 11, 2024 to July 16, 2024
EPS board assemblies, EM battery pack, Arduino board, power supply, multimeter
None
Use the ESD safe mat for all these inspections
None
R-LIB-PWR-019 [5327]
Raw Data:
Note that in this test, the protection circuit was triggered when the battery voltage was becoming higher than 7.4 V during charge or less than 4.2 V during discharge. Note that the coulomb counter was able to measure the coulombs in and out of the battery and because of the lower discharge current used in the test, the number of the coulombs out is less than the coulobs in.
Board Assembly:
UMS-0587-EM
Detailed Instructions:
Protection Circuit:
Connect 2 power supplies at the same input voltage of 6.4V with a maximum current draw of 0.5A to the board’s battery input pins (Not sure which pins).
Adjust both power supply voltage inputs at the same time in a range from 3V to 8V and take note of which voltages are within the powered range.
Coulomb Counter:
Connect a power supply at 6.4V with a maximum current draw of 0.5A to the board's main power input pins.
Connect a battery pack to the board's battery input and measure its voltage (using code)
Run the testing script which charges the battery for a set period of time (TBD) and read the output of the coulomb counter.
Connect a controlled load of (X amount) A to the board so simulate discharging and run the associated testing script for a set period of time (TBD) which will read the coulomb output.
Item
T3
Test Item
Test the functionality of the 100 second timers and non-volatile latches
Test Specification
This test is to verify that all three 100 second timers work correctly and will not allow premature function of the spacecraft. The volatile latches will also be tested to verify that they hold their value after a single event upset.
Judge Criteria
The overall output of the timers shall turn no earlier than 100 seconds. Volatile latches shall keep their values after the board resets
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
July 23, 2024 to July 23, 2024
EPS board assemblies, power supply, multimeter, timer, digital oscilloscope
None
Use the ESD safe mat for all these inspections
None
Raw Data:
Board Assembly:
UMS-0587-EM
Detailed Instructions:
Power up the board using the Board power-up procedure
Connect the test points T3 and T4 to oscilloscope and start capturing. After about 30 minutes the output should switch to logic 1 (about 5V DC).
Measure the time for both analog timers and document the results in the table above.
Below, we can see the probed signals for Timers output and Reset.
Signal D0 is resetting the timers, D1 is analog timer 1 output, D2 is analog timer 2 output, and D3 is the main power bus voltage (swithing on).
Item
T4
Test Item
Test the functionality of load switches and the current sensor integrated to it
Test Specification
Follow the instructions provided below for all 8 load switches to verify they can switch the power on and off when needed and limit the current if a short circuit happens.
Judge Criteria
For all 8 load switches the following shall be verified:
*Ideal diodes prevent flow of current when Vin<±0.05V
*Current sensors accuracy =±50 mA
*When EN is off: current<0.1 mA
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
July 23, 2024 to July 30, 2024
EPS board assemblies, variable power supply, fixed 5V power supply, electronic load, multimeter, EM battery pack
None
Use the ESD safe mat for all these tests
None
R-LIB-PWR-034 [5379]
Raw Data:
Board Assembly:
UMS-0587-EM
Detailed Instructions:
Power up the board using the Board power-up procedure
Verify the communication to CCLSMs through AUX_CAN bus
COMS CCLSM shall be able to provide a maximum of 12 W (1 A at 12 V) of power for 350 seconds to accommodate COMS transceiver's required power of 10.32 W (860 mA at 12 V) for 307.2 seconds.
CDH CCLSM shall be able to continuously provide a maximum of 1W (156 mA at 6.4 V) of power to accommodate CDH's required power of 0.74W (115 mA at 6.4 V)
ADCS CCLSM shall be able to continuously provide a maximum of 1W (156 mA at 6.4 V) of power to accommodate CDH's required power of 0.74W (115 mA at 6.4 V)
Item
T5
Test Item
Test the temperature sensors on the power subsystem.
Test Specification
Follow the instructions provided below for all 7 temperature sensors to verify their functionality. Use a thermometer as a truth measurement and compare the measured temperatures.
Judge Criteria
The temperature readings shall agree with the thermometer value with 5% accuracy.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
July 30, 2024 to July 30, 2024
EPS board assemblies, variable power supply, fixed 5V power supply, Thermistors, thermometer.
None
Use the ESD safe mat for all these tests
None
R-LIB-PWR-031 [5366]
Raw Data:
Note that THERM_1 and THERM_2 will measure battery saddle temperature, THERM_3 through THERM_6 measure solar panel temperatures, and THERM_7 measures power board's internal temperature.
Board Assembly:
UMS-0587-EM
Detailed Instructions:
Power on the board using power supply.
Using the STLink V2 programmer that’s connected to the program port on board, open main.c code. The function that will be used for this test is readTemperature.
Running (debugging) the code, we are able to see in the variable window the return value of the function ( ii (number of the sensor) and mybat(sensor reading)). This is the measured temperature to record.
Using the Perfect Prime: DataLogger Thermometer, we will be measuring the true temperature with this device. To use the thermometer, place the probe on the end of the thermistor.
***Note, THERM_7 is an onboard thermistor and is located on top by a yellow switch (R43). You check it by using the code. Place another true temp probe on it.
Item
T6
Test Item
Test the watchdog timer for the microcontrollers.
Test Specification
Follow the instructions provided below for all 2 WDTs on the power board.
Judge Criteria
the WDT shall initiate a reset for the MCU if it doesn’t detect a pulse on the heartbeat pin for longer than 1 second.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
August 3, 2024 to August 3, 2024
EPS board assemblies, variable power supply, fixed 5V power supply,
None
Use the ESD safe mat for all these tests
None
Raw Data:
Board Assembly:
UMS-0587-EM
Detailed Instructions:
Find the input and output pin (P1 is output, P4 is input pin). Probe the pins and see if you see a pulse in the input, you should not see output and vice versa.
Watchdog 1 is shown below:
Watchdog 2 is shown below:
Item
T7
Test Item
Test the main power bus to verify that the positive line can be switch on/off
Test Specification
By programming the digital timer and logic MCU, turn the SSR-EN on and measure the voltage at the MPB pins
Judge Criteria
The MPB voltage shall be equal to the battery voltage after the power bus inhibit is released.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
August 3, 2024 to August 3, 2024
EPS board assemblies, variable power supply, fixed 5V power supply,
None
Use the ESD safe mat for all these tests
None
R-LIB-PWR-036 [5388]
Board Assembly:
UMS-0587-EM
Bus inhibit active. the voltage at output is close to zero even though input voltage is 6.4V.
Bus inhibit released. the voltage at output is equal to input voltage at 6.4V.
Item
T8
Test Item
Test the main power bus to verify that the ground leg can be connected/disconnected from battery negative terminal
Test Specification
By programming the digital timer and logic MCU, turn the APB-EN on and measure the voltage between the GND and battery negative terminal. It will show zero volts when the ground leg is properly connected.
Or by connecting the flight switch to battery negative, the ground will connect to battery negative.
Judge Criteria
close to zero ohms between ground and battery negative terminal shall be measured when inhibit is released.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
August 3, 2024 to August 3, 2024
EPS board assemblies, variable power supply, fixed 5V power supply,
None
Use the ESD safe mat for all these tests
None
Board Assembly:
UMS-0587-EM
the 3 switches dedicated to deployment separation are annotated in this image.
Ground inhibit separating the connection between battery negative terminal and power GND
Ground inhibit connecting battery negative terminal to power GND.
Item
T9
Test Item
Test the power electronic board to verify it can communicate with CDH through CAN and with CCLSMs through AUX_CAN
Test Specification
Verify that 2-way communication between power and CDH and CCLSMs can be achieved.
Judge Criteria
data can be exchanged between the transmitter and receiver and in case of corrupted data, retransmission of data is supported.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
September 15, 2024 to September 17, 2024
EPS board assemblies, CCLSMs, CDH board, variable power supply, fixed 5V power supply,
None
Use the ESD safe mat for all these tests
None
R-LIB-PWR-039 [5402]
Board Assembly:
UMS-0587-EM
We can see that when the software attempts to communicate with the CDH, CAN signals appear on the logic analyzer and the appropriate breakpoint gets triggered on the CDH side to indicate that a proper data transfer was completed.
Item
T10
Test Item
Test the RBF inhibit functionality.
Test Specification
Test the power electronic board to verify that it can keep the satellite unpowered when the remove before flight (RBF) pin is inserted.
Judge Criteria
main power bus shall be turned off when the RBF pin is inserted.
Samples
3 PWAs
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
September 15, 2024 to September 17, 2024
EPS board assemblies, variable power supply, fixed 5V power supply,
None
Use the ESD safe mat for all these tests
None
Board Assembly:
UMS-0587-EM
Results: If the separation switch is activated (satellite is deployed), the satellite stays unpowered indefinitely if the RBF pin is inserted. After RBF pin is removed, the satellite starts a 100-second-long timer after which the satellite turns on. See pictures below. The pictures show that in the beginning, the RBF pin is inserted even after a few minutes has passed, the satellite stays off (a small amount of power consumption on the power supply indicates the timer and RBF logic's power consumption.) After around 2:30 minutes (150 seconds), the RBF pin is removed and the timer starts counting. Around 100 seconds after the RBF is removed, the satellite is turned on.
start of test, RBF is inserted.
After 150 seconds, RBF is removed. The power is still off.
100 seconds after removing the RBF, the satellite is powered on.
Start Date:
October 11, 2024
End Date:
November 4, 2024
Part Name:
Application:
Quantity:
Item
P1
Test Item
Visual Inspection
Test Specification
Inspect the batteries for any deformation, bulges, dents, leaks, discoloration, and cracks on the batteries.
Remove the plastic covering of the cells to allow for clear view of the cells
Judge Criteria
There shall be no such defects or flaws stated in the test specifications in any of the received batteries. Report all findings.
Samples
EM, FM
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
October 11, 2024
EM batteries, voltmeter
None
Use the ESD safe mat for all these inspections
None
Raw Data:
The batch number for all of these batteries are "BUR 030020586". The batteries were purchased from battery space in September 2024.
UMS-0036-01: no visible damage
UMS-0036-02: no visible damage
UMS-0036-03: small specs of rust near the positive terminal. no other visible damage
UMS-0036-04: no visible damage
UMS-0036-05: no visible damage
UMS-0036-06: small specs of rust near the positive terminal. small dent visible on the side
UMS-0036-07: small specs of rust near the positive terminal. no other visible damage
UMS-0036-08: no visible damage
UMS-0036-09: no visible damage
UMS-0036-10: no visible damage
UMS-0036-11: small specs of rust near the positive terminal. no other visible damage
UMS-0036-12: no visible damage.
Item
P2
Test Item
Measurement of physical characteristics
Test Specification
A. The length, width, and height need to be measured and recorded. Length, width, and height are defined as the following:
Length: The horizontal length of the battery with the serial number upright.
Width: The vertical length of the battery with the serial number upright.
Height: The smallest dimension.
Measurements should be recorded with 0.1mm precision.
B. Record the mass of each cell/battery with 0.1g precision.
Judge Criteria
Length: 65 ± 0.6 mm
Width/ Diameter: 18 ± 0.6 mm
Height: N/A*
Mass: 40 ± 0.5 g
Samples
EM, FM
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
October 11, 2024
EM batteries, voltmeter
None
Use the ESD safe mat for all these inspections
None
Item
T1
Test Item
14-day Open circuit voltage test
Test Specification
Discharge each cell at constant voltage to the minimum allowable voltage specified by the manufacturer’s data sheet and terminate the discharge when current tapers below C/100. Record the OCV at discharge termination for each cell. Rest cells for 14 days while monitoring (checking) the OCV for each cell on days 1, 3, 7, 10 and 14.
Judge Criteria
Cells with declining voltages >2.0mV shall be rejected.
Samples
EM, FM
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
October 21, 2024 - November 4, 2024
EM batteries, voltmeter
None
Use the ESD safe mat for all these inspections
None
• None of the cells had declining voltage of more than 2.0 mV (ΔOCV<-2.0 mV), therefore all the cells passed this test.
• Note that the largest delta happens between days 1 and 3. This could be due to the battery’s chemicals stabilizing after being fully discharged.
Item
T2
Test Item
Fully charge the batteries and measure the capacity
Test Specification
Fully charge the batteries at 1C rate (1500 mA charge current) and note the mAh charged for each cell. Use this value as a baseline for battery capacity.
Judge Criteria
Cells capacity shall fall within 1350-1650 mAh.
Samples
EM, FM
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
November 4, 2024
EM batteries, voltmeter, Battery charger (HiTEC X4 AC Pro)
None
Use the ESD safe mat for all these inspections
None
According to the test results below and the judge criteria for this test, all cells pass and show acceptable charge capacity.
Item
T3
Test Item
Open Circuit voltage
Test Specification
Measure the Open Circuit Voltage (OCV) on the flight cells using a multi-meter and record the value for each of the cells. Measurements should be recorded with 0.1 V precision.
Judge Criteria
Open circuit voltage falls within range 3.2 to 3.4 V
Samples
EM, FM
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
November 4, 2024
EM batteries, voltmeter
None
Use the ESD safe mat for all these inspections
None
According to the test results below and the judge criteria for this test, all cells pass and show acceptable OCV.
Item
T4
Test Item
Closed Circuit voltage
Test Specification
Ensure that the flight battery is at least charged to the manufacture’s recommended level before proceeding. After setting up the programmable load to a constant current of C/2, load the battery and wait for 60 seconds before recording the Closed-Circuit Voltage.
Judge Criteria
Closed circuit battery voltage falls within range 3.1 to 3.4 V
Samples
EM, FM
Test Period:
Test Equipment:
Major Problem:
Warning:
Recommendation:
Verification Activities:
November 4, 2024
EM batteries, voltmeter, Battery charger (HiTEC X4 AC Pro)
None
Use the ESD safe mat for all these inspections
None
The cells were loaded with a constant current of 0.7A and the CCV was recorded 60 seconds after applying the load. According to the test results below and the judge criteria for this test, all cells pass and show acceptable CCV.