More of a brief note but - in between other distractions the layout has been up and run, and while it was out, I took the opportunity to sort out some outstanding electrical business
The NCE PowerCab does not seem to have full short-circuit protection. I'm not sure of the technical details but I've finally installed some additional protection. This takes the form of a cheap and basic circuit breaker from Halfords, price £1.70 or so.
As I understand it , the PowerCab doesn't shut off the juice in the event of a short. This little circuit breaker may not be a proper fast-acting breaker - those cost £20-30 - but it will turn the current off fairly quickly, limiting the time the PowerCab is exposed to any short. Instead of a screen full of gibberish and a reboot (pull out the plug, put it back in) you get a blank screen and a reboot . It's a damage limitation device , installed just behind the system socket on one wire of the feed into the traction bus
While I was about it, I had a go at making the Kadee electromagnets work. When the layout was originally built , I installed three Kadee electromagnets beneath the track in the station - in a fit of enthusiasm for flash kit and clever tricks.
I tried wiring one up ages ago - but nothing seemed to happen. I was under the impression that electromagnets were supposed to make a loud buzzing noise , and I assumed that the electrical joints were bad somewhere - presumably due to a failure adequately to strip the lacquer off the ends of the coil wire. (The lacquer made it impossible to perform the usual continuity test with the multimeter to check the joint - so I was stumped as to where the bad joint was). At that point I gave up...
After a lapse of several years, I had a go at wiring the second electromagnet. I stripped back the lacquer using an emery board, carefully soldered up the joints, connected the transformer. No buzz.
Then I noticed the coil was jolting when the button was pressed. This could not be mechanical action of the fine wire - and the coil was warm. We were in business. A check with a couple of parcels vans revealed that the electromagnets were effective. One remade joint later, and the electromagnetic uncouplers for both Platforms 1 & 2 were working
(The transformer used is a switchable voltage DC power supply with a highest setting of 15V , which was being heavily discounted in Maplins a few years ago. It is rated for 5A at the lower voltages - no doubt a bit less at 15V. Kadee's recommendation is for 5A at 16V DC / 18V AC - my transformer gives a bit less than that , but it still seems to work)
How much practical use these gadgets will be is a moot point. I installed them suitably placed to split 2 x 153 units , (or 153+Pacer) so they are too far down the platform to suit uncoupling a class 31, though they may suit a 128 unit. Practical experimentation is called for