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Restoration diary

As one of RRRG's electrical officers I will write about my specialist field as well as general reports of work on site.

December 11th 2010

Dave Rolfe continued measuring, cutting and fitting flooring into the no.1 cab of Renown. Chris Bodell painted some more cab fittings & panels, and varnished the completed flooring in no.2 cab, Ian & Pete fitted two big end bearing caps now the suppliers have sent Ian the nuts for the stretch bolts that they were out of stock of. They were in the process of fitting a third cap but one of the four stretch bolts seemed unwilling to fit, so they had to remove the cap to see what the problem was. Nothing was obviously amiss, but by then the light was fading, so they didn't refit the third cap. My two GWR mates (Matt & Roger) who had visited a few weeks ago again came up, this time armed with some 185mm through-crimps and a large hydraulic crimper, so in the morning we did a test joint to see how it looked, and the result was encouraging. After crimping both sides of the crimp, a layer of heat-shrink sleeving was applied and heat-shrunk. A large amount of insulation tape was then wrapped round the crimp over the sleeving, then a second layer of heat-shrink sleeving was applied and shrunk. We used the group's 1000v Megger to check if there was any leakage to earth, and the Megger result was a full-scale needle deflection to the Megger's capacity of 2 Mega Ohms (2 million ohms). Any reading over 1 megaohm is considered good, and as the Megger only registers up to 2 Meg, the actual reading would therefore have been higher, which means this type of crimp, which is rated at 11,000 volts, should be more than adequate for both the severed main traction cabling and the main ETH cabling, as the maximum expected traction voltage is around 1000 volts. If I can find someone with a higher-capacity Megger, I will repeat the insulation test. Joining the cables in this way will remove a significant amount of time, effort and expense from the work needed to complete Repulse. After lunch, we crimped the last couple of 16mm cables, connected them, then Matt connected four cables to resistors on top of the cubicle which I am too much of a shortarse to reach.

November 14th 2010
January 16th 2011

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