Review 3D printed plug shells.
Test wiring on Adaptor board #1.
Continue wiring new boards.
Review the new two-way switching unit.
Discuss installation and cabling.
Source components.
Discuss Local control panel.
Review 3D printed pallets.
Yes, it was a busy day, but it progressed at a comfortable and very satisfying pace.
The 3D printer had just started to produce a shell for the 12-way plug shells as Stephen & Laurence arrived and immediately viewed a couple of 8-way shells. These were required for the new Cinch plugs as no shells were available. Although the surface was coarse, the units were very solid and should work very well.
In the workshop, the layout and the newly wired Adaptor board #1 were set up. While Stephen and Geoff made a final modification to its wiring, Laurence tested the board using John's Planet diesel. Everything worked well.
Stephen had produced a mock-up of the two-way selector switches he favoured for the change-over areas (boards #2 & #3). As agreed the previous week, the arrangement, without a centre-off facility, was only acceptable if separate section switches were added to the Local panel. The switches used were actually 220vac SPDT push-button versions similar to the main panel section switches, but with the LED and resistors replaced with standard 5v units. Two more will be required for the two boxes.
The switching unit uses DPDT relays to switch the power source and LED indicators with the main relay circuit mimicking domestic staircase two-way switching.
Stephen talked through a wiring sketch of the new main selector switch box. He then presented two multi-cable options. Originally, a 10-way cable was anticipated and so VGA monitor leads (15-way) were an option. Then, the wiring sketch exercise showed that only 8-way cables were required for the two remote switches and so standard 8-way Cat5e network cables were tested for flexibility and were provisionally accepted. For the adaptor board DIN connections, Geoff proposed single strand wire exactly like the main loom rather than buying new wire. Most are 3-core with one 5-core and the option was agreed. While reviewing the switch wiring sketch a suitable box was discussed. Geoff retrieved the basic wooden box the main Worton Court power supplies had been housed in before the first exhibition required a non-flammable enclosure. As the new box was the right size and would never attend an exhibition, it was approved for use.
Rather than a loom, the cables will all radiate from the main box. The box brass nails down the centre will be the internal soldering posts, with terminal blocks around the perimeter for the outgoing lead connections. The board with the two relays will be located in the centre. The power supply may or may not be housed inside as well.
Geoff and Laurence moved on to wire-up board #2, whilst Stephen started making up the DIN cables.
Stephen later displayed a preliminary control panel design, for comments, and to allow the overall box size to be assessed. The two extra isolation switches were confirmed and subsequently added. Geoff was able to supply the three point switches and the 11 three-way (centre off) rotary section switches required, from his 'left-overs' box. Due to its location inside the layout, the box needs to be as narrow as possible. Designs to be investigated.
Stephen displayed the 3D printed pallets that he had painted and weathered with powders. After being challenged by Laurence to see if they fitted on the forklift truck, Stephen was able to confirm that they did.
The shelf units made 'last minute' for the Burton show (but never glued down) had worked their way out of the store room and were finally snapped for the blog.
