Power Requirements and Inverter Solution
Running a small office without interruption of your telephones and internet connectivity during loadshedding events using the Hybrid Power in a Box Uninterruptable Power supply Inverter.
Office Reception Requirements
To establish your requirements we start with a load audit.
How much power do you need and for how long?
1 PC - 50Watts
1 WIFI router – 7 Watts
1 Fibre internet box – 10 Watts
1 Cellphone charger – 7 Watts
Inverter fan – 30 Watt
Total requirement is 104 W
Capacity : Power in a Box –Small office and student model 12V UPS, 1200VA
The 12 V Battery has a capacity of 80Ah ( 80 Amp Hours) , but being a deep cycle lead acid battery, you don’t want to use more than 50% of the battery’s capacity to ensure a long battery life.
Therefore you only have 40 Ah available in your 12 V Battery 40 X 12 = 480 Wh ( Watt Hours)
For 2 hours of backup you can therefore run 480/2 = 240 Watts.
For 4 hours of Backup you can run 480/4 = 120 Watts.
Your office reception uses less than 120 Watts, so the Power in a Box can cope with 4 hour loadshedding events.
Solar addition
If you want to be able to remain running with blackouts lasting a day or more, we recommend adding a single 200W solar panel to your Hybrid UPS inverter. (Simply put the solar panel facing full sun, and plug it in to the power points provided on the Inverter)
A 200W panel will give you 200 W for about 5 or 6 hours on a sunny day. While the sun is shining, your panel will run your load (of approx. 100W ) while charging your battery. After sundown, you will have 4 more hours of backup on the battery.
The system is designed for extreme flexibility to take up to 700W of solar power in multiple panels if required, and extra batteries can be added to increase your electrical load and storage capacity.
Phase 2
Office/Training room / sales room requirements
10 laptops (40 - 50 W each) = 400 - 500 W
Inverter fan 30 W
Total requirement = 430 – 530 W
Capacity : Power in a Box –Small office model 24V UPS, 2400 VA model
The 2 X 12 V Batteries = a 24 V battery with a capacity of 80Ah.
Therefore you only have 40 Ah available in your 24 V Battery 40 X 24 = 960 Wh
For 2 hours of backup you can therefore run 960/2 = 480 Watts. Ie 10 Laptops for 2 hours
For 4 hours of Backup you can run 960/4 = 240 Watts. Ie 5 laptops for 4 hours
Solar Addition
2 Solar panels of up to 350 W each ( 700 W total ) can be added to supply more than the 480 W required to run 10 laptops while recharging your batteries.
Power in a Box Prices - March 2023
Power in a Box – Home office and student 12V UPS, 1200VA R5 999
Power in a Box – Small office model 24V UPS, 2400 VA R8 999
200W solar panel R3 000
This video provids an Introduction to small office Power in a Box an dincludes the elementary calculations required to size your unit.