Saving a 1965 Generator for heritage preservation.

[Mark W]

So, very long story short.......I got given a bit of a generator, free if you take it out! All sounds too good to be true and it was, they got the better deal financially but I got what I wanted in terms of my quest to save these items of the British electrical engineering past.

Just a few issues, it wont fit through the door, it weighs 37 tons, no access for a crane etc etc but whilst sat in the bath you can come up with the solutions.

The door that is has got to come through.

It wont fit, so I had to knock the front of the building down after getting a structural engineer to confirm this was safe!

At last access to the treasure to include the BVP17 11kv switch gear.

Generator now jacked up and ready to skate on to the low loader, at this point the site health and safety adviser came across and said that we were not to do any jacking until they had seen the lift plan, he said this to me whilst I was leaning up against the already jacked up generator!

Unit slowly being skated on to the low loader

Unit now fully on to the low loader

Finally on its way to y place after a full week of preperation.

Sat in its new location

 

[Mark W]

I forgot to say, in one of the above pictures you can see a three phase motor that has its shaft covered as if it drove nothing? It took us a while to work this out and the answer is very clever!!

The output from the generator is 3 phase 6.6 kv,1333kva, this fed a step up transformer that then fed the sites 11kv ring main. This step up transformer also had a tertiary winding to give local 415/230 volt supply to the generator building for lighting, battery chargers for the breakers and other low voltage supplies. We found out that when the generator was moved in @ 1978 a new transformer was ordered but they accidentally ordered a delta wound three phase tertrairy 415 volt winding for this building supply. They needed a single phase 230 volt supply for lighting and other single phase equipment but they had no neutral. The solution was to use that motor, with its windings rated at the maximum neutral current, run it in star and the centre point of the motors star winding gave an artificial neutral.

The excitation for the generator comes from a small 11kv/110 volt transformer located on the main switch board. Should the generator develop a huge fault prior to the switch board the voltage could collapse and it would lose available control voltage to undertake control/shutdown operations. The generator is star wind with the centre point connected to earth via a neutral earthing resistor but........in line with this single connection to earth there are several current transformers. In the event of a large earth fault that would result in large amounts of current but limited voltage at the switch board then these current transformers would then generate the 110 volt ac that was need by the control panel to shut down which I found quite clever.

All relay logic with pneumatic timers, not a microprocessor in sight!!

 

[Rockingit]

Generator pawn. Beautiful!

 

[Lucien Nunes]

Nice. Convenient for power cuts, although difficult to connect directly into the house at 6.6kV. Sixteen times as many cylinders as most peoples' backup units. I'm not good at recognising engines that modern... is it a National? What's the model so I can look it up in my Boys Book of Big Diesels?

The nearest I got to salvaging a standby plant was a unit of some 400kVA with a Paxman 12RPHX driving an ECC 415V machine, in the basement of a building slated for demolition. But there were many competing demands on our time and the generator had to be left behind.

 

[Mark W]

Nice. Convenient for power cuts, although difficult to connect directly into the house at 6.6kV. Sixteen times as many cylinders as most peoples' backup units. I'm not good at recognising engines that modern... is it a National? What's the model so I can look it up in my Boys Book of Big Diesels?

The nearest I got to salvaging a standby plant was a unit of some 400kVA with a Paxman 12RPHX driving an ECC 415V machine, in the basement of a building slated for demolition. But there were many competing demands on our time and the generator had to be left behind.

Here you go Lucien ……the new genny for the house is a paxman v6 RPH ex BT.

The w h Allen engine is open rocker gear so very good to watch!

 

[Lucien Nunes]

The eagle-eyed will spot the early-warning siren tucked under the walkway and the half of a conrod visible next to it which gives an idea of scale of the internals.

850 cu ins = 13.9 litres per cylinder, 223 litres total.

 

[James]

makes my project look like a toy car next to a JCB tyre!!

Old generator

This may be coming up as free to good home.

www.electriciansforums.net

 

[Mark W]

The eagle-eyed will spot the early-warning siren tucked under the walkway and the half of a conrod visible next to it which gives an idea of scale of the internals.

850 cu ins = 13.9 litres per cylinder, 223 litres total.

You never saw that siren did you! What siren??!! …….that damn thing has already got me into a lot of trouble

 

[Lucien Nunes]

Did you run the siren? I've never gotten around to connecting mine up. Sorry, what siren? I meant syphon. Ignore me, just waffling.

 

[Mark W]

Did you run the siren? I've never gotten around to connecting mine up. Sorry, what siren? I meant syphon. Ignore me, just waffling.

During lockdown, clap for carers I set it off……frigging hell it’s loud. Got a few complaints in the village. I own the fog horn from the rms Windsor castle that I always set off at new year, 147db …..I don’t get complaints about that just the nuclear attack siren? Don’t know why?!