Integrated Power Box
This project is actualy a version 2, but I didn't document it, and I wanted to make a couple of changes since I did the MkI. It was only a plastic utility box (the type of thing you might keep document wallets in) and not particularly strong. So, when this box came up spare, it was earmarked for this project. So, some things I wanted to achieve/do...
- Voltmeter and Ammeter to monitor (useful when in the field)
- Red illuminated switches for each power outlet (lit, but dim)
- Multiple Voltage Outputs (12v, 5v, 3v)
- USB Connectors easily accessable
- Easy to carry
- Change the Phono connectors for jack-plug type
- Run from AC mains or 12v leisure battery
- Main switch that switches everything off!
So, I started to work out what I needed and plan how to do this. I have a good friend who was able to source some of the components for me ;-) , so a full costing is not available. When I get a moment, I will research up some equivalent components...
- VoltMeter (moving coil)
- Ammeter (moving coil)
- Large black project box
- Red, Black, Blue bell wire
- 200-ish ohm resistors (for dimming the switches)
- 6 illuminated round 12v rocker switches
- 3 small project boxes
- 4 port USB hub + 5v supply
- 5 pin 240 degree DIN socket + plug (for the CCD Camera cable)
- 3 pin click-lock socket and plug (mains)
- 12v Cigar Socket (lesiure battery input - also gives additional output when on mains)
- 4 A-B USB Connectors
- 1 B-A USB Connector
- 4 short USB cables
- PC Fan
- 5 inch speaker grill (to cover the hole for the fan)
- 5 way automotive fuse holder
- 5 2.1mm panel mount jack socket + 5 short 2.1mm plugs
The build was fairly straightforward - it just needed some planning. The electrics are not that difficult, competency with a soldering iron is required, but even that could be done away with by using crimps and spade connectors - certainly for the most part.
The basic circuit is:
- From the + of the 13.2v bench supply to +ve side of the main switch
- From the load side of the main switch to the +ve side of the ammeter
- From the -ve of the ammeter to the +ve side of each switch
- One of the small boxes was used to split one lead from the ammeter to 5 feeds to the switches
- From the load of each switch to one side of each of the fuses
- From the other side of the fuse to the +ve side of each of the panel mount sockets
- From the -ve side of the sockets to the -ve terminal of the bench supply
- Again, another small box used to consolidate the 5 leads down to 1
- Each switch then had a resistor attached to the -ve leg before connecting to the -ve terminal to reduce the brightness
- The voltmeter is wired across the terminals of the bench supply
- The 12v-5v transformer for the USB hub is wired to the -ve side of the ammeter and the -ve terminal of the bench supply
- The PC fan (to draw heat away from the bench supply) is similarly wired
I couldn't figure out how to make a step-down transformer - well, not in the time frame I had - and it was only a idea as something that could be fun to do, so this had to go. The result is that I have a power box that keeps all the necessary electrics needed in place, is easily transportable and requires just two leads - one USB and one power!
It also means that the cables running from the scope and mount can be kept tidy and I no longer worry when slewing or doing pier flips, that things will get snagged. For a few hours investment, a good result!
01 Starting box
02 Cable entry
03 Top Plate
04 Rear
05 Interior
06 Positioning
07 Top done
08 Voltage
09 Wiring
