Sari-sari store freezer through a brownout: battery, inverter and hours
12 V 100 Ah LiFePO4 battery, 1000 W pure-sine inverter, a chest freezer and two LED bulbs. The panel shows the compressor state, the current and the hours left. A chest freezer runs at only about 120 W, but its compressor starts at six times that and cycles all day, and the ice has to survive eight hours of brownout. A 12 V 100 Ah LiFePO4 battery and a 1000 W inverter do it: the start surge is within the inverter’s reach, the average draw is about 6 A, and the battery lasts the night with the store’s lights on too.
Build it in the labGuided build, test sheet and fault finding, free in your browser.
Parts list
Test procedure
Each test has an expected value and a pass range, like a factory test sheet:
- The compressor starts on the 1000 W inverter
- Battery current with the compressor on and both lamps
- Hours left while the compressor runs
- Compressor off between cycles
- A 150 W car inverter instead
How it works
What it does: 12 V 100 Ah LiFePO4 battery, 1000 W pure-sine inverter, a chest freezer and two LED bulbs. The panel shows the compressor state, the current and the hours left.
Build it (guided or ready-made), then run its test procedure below. Every test has an expected value and a pass range, just like a factory test sheet.
Background
Pang-brownout sa tindahan: the freezer is the load that matters, and this is the smallest setup that keeps it cold.