TPEE Commercial MPPT Testing

SunVault (The Not-Sketch Plastic Box Containing lead acid battery that totally didn’t blow up at some point and take a hand with it. There are 9 batteries each with 12V nominal, giving a total approximate battery voltage of 108V.
Lightbulbs (E-loads to discharge battery)
LV Battery (To power CAN)
CANdapter
Array 1 on 2024 - 2026 Car: The array that we are currently using for this set up is the larger back array on the 2024-2026 car and rated at approximately 80V.
- Array 2 is the front array.
Fluke (Hall Current Sensor)
Voltmeter

Ts(this) MPPT is working now straight up.

Realtime Data:
Realtime Data Tab
- To read Realtime Data click Stream Realtime Data
  Stream Realtime Data button
- Click on Power, Voltage and Current, and Temperatures tabs to read corresponding data

Install CANdapter Tool
- view reading on Message Analyzer
Install CANdapter Driver
Install the Java Programming Language
Connect to CANdapter
- Connect High to CAN-H and Low to CANL
- Connect LV power supply (12V) to VCAN+ and VCAN-
Ensure that Baudrate on MPPT is set to 125kHz (standard CAN baudrate) and that the CANdapter Tool is also set to 125kHz
Clone Python Script to interpret CAN messages

Battery
- Connect Power to Vbat+ and Ground to Vbat
Array Connection
- Connect Power to Vpv+ and Ground to Vpv-
- On Daybreak:
  - Array cord 1 is for the back array

Discharge SunVault (Led-Acid Batteries): In order to be able to charge the battery we need to make sure that it is not fully charged. Since it is rated at approximately 108V, we need to discharge it by a few volts in order to test the array. It should take about 10 - 15 maximum to discharge the array to around 105V.
Pre-charge:
- flip LHS switch Precharge and RHS switch to Power on (after precharge) → let it run for a few seconds
Charge:

We tested the commercial MPPT with the array on the car and with SunVault.

Configuration 1: Connected Lightbulb in Series Panel and SunVault in series
- Takeaways: SunVault (battery) can discharge power because the lightbulbs lit up
Configuration 2: Connected Array to MPPT in series (with computer plugged in to MPPT)
Connections for Array (left two) and SunVault (right two)
- Takeaways: Power LED and Limit LED were lit up green. The power never entered any unsafe voltage regions. The Up LED and down LED were both flashing (inconclusive). When probed, array outputted 60V - 70V.
Configuration 3: Connected Array to MPPT to SunVault in series (no computer plugged in to MPPT)
- Takeaways: MPPT power LED does not light up. When probed, array outputted 60V - 70V. When probed, battery was connected (100V probed on MPPT to battery connection). Battery was not charging because there was no current flowing from MPPT to battery.
Configuration 4: Connected Array to MPPT to SunVault in series (computer plugged in to MPPT)
- Takeaways: Same as Configuration 2 (LEDs were lit up, but inconclusive). Output for array voltage and battery voltage was same as Configuration 3.

SEC-B75-7A Documentation

Next Step: The COM port LED never lit up in any of the configurations. According to Hardware documentation, in order to charge the battery and have the device fully on (and output to the Realtime Data Tab) we must have higher than 6V on CAN-bus voltage. We suspect, that in order to charge the battery, we need to have the COM port LED turn on GREEN first.
Note: Helpful connections diagram for COM

Configuration 1: Connected LV power supply (12V) to VCAN+ and VCAN- and connected CANdapter to CANL and CAN-H
- Takeaway: Power LED did not turn on, so we decided to pre charge the MPPT (requires minimum of 30V of precharge)
Configuration 2: Same as Configuration 1 but connected Vbat+ and Vbat- to the SunVault and precharged
- Takeaway: Power LED turned on, still no reading on CAN
Configuration 3: Same as Configuration 2 but changed baudrate on the CANdapter Tool to 250kHz based off of initial configuration on the Reboost Tool (User Settings Tab)
- Takeaway: CAN LED turned on and we got a CAN reading
Configuration 4: Same as Configuration 2 but flashed a baudrate of 125kHz onto the MPPT to match CAN baudrate standard on Daybreak and changed baudrate on the CANdapter Tool to 125kHz
- Takeaway: CAN LED turned on and we got a CAN reading
Configuration 5: Same as Configuration 4 but we connected Vpv+ and Vpv- to array
- Takeaway: All LEDs were on. When probed, array outputted 60V - 70V. When probed, battery was connected (100V probed on MPPT to battery connection). Battery was not charging because there was no current flowing from MPPT to battery.
Configuration 6: Same as Configuration 4 but we connected Vpv+ and Vpv- to HV power supply at 80V
- Takeaway: Outcome same as Configuration 5

Configuration 1: Same Configuration from 1/25/2025
- Not much progress, fixed wire management

Configuration 1: Same as Configuration from 1/25/2025 but we flashed “Enable Output” and discharged battery to 105-110 V
- Got reasonable output from the MPPT and charged battery.
Next Steps:
Pictures from RealTime Data:

All connections seem to be right
- we have a minimum of 6V on CAN
- Precharge to 30V
Still no current flowing into the battery and data shown on the Realtime Data tab are inconclusive
Next Step:
- Understand configurations on the Reboost tool (maybe helpful to look at given code) to see if we have to enable anything in user settings get an output from the MPPT

Notes:

Purple : Positive Side
When we have just can turned on, boost is enabled for some point even though battery is off and array is plugged in. Sounded like it was boosting bc of the clicking noise. No current across the battery (to or from).
30 V when back array is covered with a tarp.
Fault: Output Over -