Retort stand - custom made
This retort stand can support more than a kilogram at the end of a long clamp projecting out opposite from the base. The ballast is five pounds of lead shot. I built this because I prefer to work on the opposite side from the base, which commercial stands are too light to permit. The support rod is 0.5 inch diameter hollow 6063 aluminum with 0.115 inch wall.
Battery backup power for a small freezer
The following equipment provides me with auto‑switching backup power for a manual defrost "Arctic King" 3.5 CuFt chest-style freezer maintaining a temperature of -24 to -27 degrees C. The system powers the freezer for 61 hours using ~80% of the battery discharge capacity. The freezer draws ~55 watts of power when running (probably ~50% of the time) and briefly more during compressor startup.
The components of the backup system are these:
- Lithium-Iron-Phosphate (LiFePO4) battery pack: "12V OWL MA12V OWL MAX 2 LifePO4 - 228Ah" from BigBattery.Com.
- Charger: "PEVO-12V-C12V" from BigBattery.com.
- Battery-to-inverter cables: Anderson SB175 gray connector to 5/16 ring lug terminals on 18 inch long 4‑Gauge AWG copper cable from BatteryCablesUSA.
- Power inverter: 12-volt 600-watt pure sine wave inverter, 1200 watt surge capacity.
A larger inverter can be used in this application but will be less efficient, wasting battery capacity.
- Automatic transfer switch: Xantrex 808-0915 PROwatt SW Transfer Switch, 15 Amp, 80 millisecond.
- Two NEMA 5-15 electrical connectors: 3-wire, 15 Amp, one receptacle and one plug.