Low Voltage

Low Voltage Supply

As part of the restructuring and the relocation of the shack I purchased a mains PDU and so I thought it would be useful to have a similar facility for the 12 volt supply. Most of the accessories require a 12 volt supply, either for operation or for illumination. Annoyingly some of the devices either don't have a power switch or it is located on the rear which is inconvenient when powering up or down.


The Components

With the shack being built around a 19 inch rack mount design the obvious design choice was to construct a rack mount switched distribution assembly. In cas you hadn't worked out my purchasing patterns it was off to that auction site again. Although I'm a Liverpool FC supporter blue is my favourite colour so I bought 10 blue LED rocker switches, Anderson PowerPoles, cable, spade connectors, tag strip, digital volt and ammeter and a pair of 4mm terminal posts.

The Case

To house everything I got a 1U high short form ABS rack mounting case. I chose ABS for two reasons, firstly it was less expensive than metal and secondly because it is easier to work with when you only have simple tools. The case was sourced from Top Quality Tools

Rack Case

Rocker Switches

As I said before blue is my favourite colour so the obvious choice for the rocker switched was the blue LED type. Naturally as this is part of the 12 volt supply I bought the appropriate voltage switches. They have 6mm spade terminals so it was easy to use crimped connectors with the insulating boots.

LED Rocker Switch

PowerPole Mounting

The PowerPole connectors mounted on the rear of the case are housed in the snap in bulkhead receptacle housing. Unusually I didn't get these from eBay but from Torberry Connectors.

Bulkhead Mount

Current and Voltage Meter

In order to monitor the voltage and current a small digital panel meter was procured from eBay.



A simple wiring colour scheme was used 

  • Red - feed to outlets from switches
  • Orange - 12 v feed to switches
  • Black - negative return to a common 
  • Blue - low current negative from LEDs in rocker switch
  • Purple- low current positive to master switch.