Matt sent Revolt Lab this great battery backup project for Occupy Philly.
Battery bank for your Occupation. In the end we will go through a battery and cable sizing exercise.
Occupy Baltimore (OB) organized a meeting at a local church which brought about 200 concerned citizens together. It was decided then to occupy McKeldin Park in the Inner Harbor of Baltimore, MD at 12 noon on October 4th, 2011.
Occupy Philadelphia (OP) spilled out from an organized meeting at a local church with more than 700 people. Committees and list serves began that night to prepare for the 9am occupation of City Hall on October 6th, 2011
Occupy Baltimore, Occupy Philadelphia, Occupy Wall Street, OCCUPY EVERYTHING
First we wanted to build some battery back-up power boxes for Baltimore. After buying the parts and taking them down to OB we found out that they had power. So we built the boxes and drove them up to Philadelphia.
The Tech Tent also had power at Philly for the computers, speakers and stage. So the first two battery boxes went to the Medical Tent at Philly to keep their walkie talkies, cell phones and laptops charged up.
I have detailed the parts, prices and effort below in hopes that more people find a way to keep the computers, networks and live stream up for those of us who cannot attend every night.
WARNING: Batteries pack a punch so do your homework before working with anything electric.
ITEM – Description (PRICE) – WHERE TO BUY
BATTERY – 55Amp-hour, SC34DU, Optima Yellow Top AGM Lead Acid ($150) – INTERNET
BOX – Stanley Roller Tool Box ($20) – LOWES
INVERTER – 500Watt Inverter includes two 120VAC outlets and one USB ($40) – LOWES
MISC – Wood and Screws ($15) – WHEREVER
- 4×4 at 13.75” long
- 4x4x4 block
- 2×2 at 17.25” long
- Screws, 1”
TOTAL $225 USD
Drill with 1/4” drill bit
Screwdriver and/or screwdriver bit for drill
Fortunately you only need one charger for all the battery boxes you make so I will not incorporate it into the base cost of each unit.
OPTIONAL ITEM – Description (PRICE) – WHERE TO BUY
CHARGER – 10A Battery Charger with AGM Battery Option ($50) – PEPBOYS
POWER STRIP – Six (6) 120VAC outlets ($5) – LOWES
INVERTER – 800W Inverter includes two 120VAC outlets, one USB and Display ($80) – LOWES
INVERTER – 750W Inverter includes two 120VAC outlets, one USB and Display ($75) – NAT’L AUTO
INVERTER – 500W Inverter includes two 120VAC outlets, one USB ($40) – HOME DEPOT
INVERTER – 800W Inverter includes two 120VAC outlets ($80) – HOME DEPOT
INVERTER – 400W Inverter includes two 120VAC outlets and two USB ($60) – PEPBOYS
INVERTER – 3000W Inverter ($350) – PEPBOYS
BOX – Big Roller Tool Box to hold multiple batteries ($50) – LOWES
MULTIMETER – Voltage, Current and Continuity Checker ($25) – KMART
Now that you have the parts and the tools begins the fun part. You have to open up the front of the Stanley box to get the battery in because it’s just a little bit too big. Be careful not to break the chintzy plastic tabs holding the tool box together. Pull the sides out while pulling the front piece forward.
First put the 4×4 block in the bottom against the back. Put four screws through the rear bottom of the box to hold the 4×4 in place. It is much easier on your wrist to put some pilot holes for your screws in and then sink the screws into the 4×4 with your screwdriver.
Now put the battery in the box on top of the 4×4. Put the 2×2 piece across the top of the battery, behind the terminals (+ and -) and in front of the raised plastic area on top. Push the 2×2 piece down snug and place one screw in each side of the tool box to keep the wood fixed.
Now slide the battery to one side and place the 4x4x4 block beside the battery to keep the battery stable and in place. Remove the block and VERY CAREFULLY drill two holes through the back of the tool box where the block will sit. Then put the block back beside the battery, turn the toolbox around and put two screws into the block to hold it in place. The battery should not be able to move at all.
Next is putting the inverter into the top of the battery box. Open the top of the box and take out the top shelf. Drill two 1/4” holes from the top to the bottom where the battery is located. Now carefully use the 1/4” drill bit to open up the holes wide enough to feed the RED and BLACK inverter cables through the box. Be careful not to break your drill bit as I broke all my smaller bits making these boxes.
Pull the cables up through the holes from the battery compartment up to the inverter compartment. Connect the RED to the positive terminal of the inverter and the BLACK to the negative terminal of the inverter. ALWAYS CONFIRM THE + AND – TERMINALS ARE CONNECTED CORRECTLY BEFORE CONNECTING TO ANY BATTERY.
Connect the Red clamp to the positive terminal on the battery first and then connect the BLACK clamp to the negative terminal. You will see a little SPARK as those electrons just can’t wait to complete the circuit to your inverter.
Now you can turn on the inverter and watch the green light comes on. CONGRATULATIONS, you now have 55A-hr battery connected to a 500W inverter (2 x 120VAC outlets with one 5VDC USB slot) ready to power your OCCUPATION. If the green light blinks and the inverter stops working, simply turn the inverter off and on and the green light should come back on steady and ready to go. You can also plug in a power strip to get more outlets for low power electronics.
If you have any questions, do not hesitate to contact me, Matt Weaver, firstname.lastname@example.org