A further visit to LMS enabled completion of a number of outstanding electrical tasks, including:
- Fitting a protective cover to the cable joints between the inside front left lighting frame lighting strips
- Installation of flexible conduits, wiring and LED strip for the front buffer beam lighting
- Survey around the reverser stand in preparation for refitting the sander indicator wiring, boxes and air pipes
The refitted LED inside frame light strips beside the middle engine had an exposed joint at their coupling to the conduit system. This is an area that is prone to impact from tools, so a custom brass cover has been fabricated to protect it. This was fitted in place.
The job to install front buffer beam lighting was completed, apart from final fitting of the LED strip and connection to the system. This apparently simple task was made mode complex because the underframe lighting circuit does not currently progress further forwards than the under-running plate box behind the cylinder on the fireman’s side. This meant that we had to install new wiring in the original 32mm conduit that runs from this box, past the cylinder and down to the turbogen connection box. After trying three different styles of electrical wiring rods, a combination of a nylon one and a tubular steel affair got through the conduit and its four bends and the wires were successfully pulled in. A useful discovery was that, back in 2007, Paul Depledge had thoughtfully left spare terminals in the under-running plate box to connect the new wiring into the underframe lighting circuit, which simplified this part of the job. Finding these raised a smile. The next challenge was to get the wiring through the frame and finalise the location of the lighting strip. Fortunately, the front buffer beam umbilical wiring already passes through the frame on its way to the umbilical, so this conduit was used to gain access to the existing box behind the buffer beam. Discussion with DTW resulted in a simple arrangement for the LED strip which required minimal fabrication and no new holes drilled in the engine. A plate was made to sit above the existing flange that supports the buffer beam pipe connection brackets. This gives the lighting strip good physical protection behind the flange. The plate was drilled and tapped to take the LED strip trough. We were able to use the very last length of brass trough that we have in stock for this, which happened to fit the available space perfectly. The LED strip was made up and tested, together with the 10mm flexible conduit connection. LMS will now (as volunteers) paint the new plate, ready for installation during the next visit.
The sander indicator pressure switch box (which flashes an LED to remind the driver when the sanders are operating) used to be located in an unsatisfactory position under the floor on the driver’s side. The Rose box has corroded badly in the very unpleasant environment, and the small plastic air pipes that connect to its pressure switches were prone to being crushed and broken. In consultation with DTW a new location has been identified for the box on the left of the reverser stand. This will allow a much more satisfactory connection to the forward and reverse air pipes, close to the sander lever. It will also be easier to wire into the LED box and the rest of the electrical system. The new JRU has a channel to detect when the sanders are being used and additional wiring is being provided for this. A new box for the switches will be constructed and LMS will arrange for the fitting and making the air connections when they re-pipe the sander plumbing on the reverser stand. The existing LED box (which fits in the side of the straight air brake bracket) will be refurbished and reused.
The great majority of the complex and risky electrical work on the loco is now complete. Remaining electrical jobs to be carried out at LMS include:
- Final fitting, connection and testing of front buffer beam lighting strip
- Reconnection of Turbogen Switch Box wiring (currently disconnected for welding on the engine frames)
- Once the cab goes on, connection of all electrical systems between engine and cab (including final modifications to make everything fit in some very confined spaces)
- Making up the new sander indicator box and wiring, refurbishing the LED box, final fitting of boxes to reverser stand and air brake bracket
- Refitting and rewiring of the front top marker lamp (on the top of the smokebox)
- Refitting the front lower marker lamp (after the front buffer beam footplate goes on)
- Refitting the front right and left marker/tail luminaires
- Testing all the engine electrical systems as far as possible (without the tender)
- Making up and testing the new engine-tender umbilical cables (a Darlington Works South job, necessitated by the higher ETCS currents)