OHLE immunisation

[Deleted]

Several posts in both uk.railway and uk.transport.london have bemoaned the fact that the OHLE on the West London Line, which passes beneath the H&C west of Latimer Road, cannot be extended south beyond Mitre Bridge Junction until the H&C is resignalled in 2013.

Does anyone know if the Hammersmith branch really is on track to be resignalled in 2013, and subsequently immunised against OHLE?

[Colin]

I would think it's possibly a tad early to tell at this stage - given that none of the new signalling work has even started yet.

[Deleted]

Actually, it has - I read somewhere that the BTR currently in progress on the Met Main is related to the grand resignalling.

[Colin]

I meant on the stretch of track that you are specifically asking about - but I take your point.

[tubeprune]

ISTR that the Uxbridge branch still has 33Hz track circuits so it would have to be immunised before any 3-phase AC traction was allowed out there. Can anyone confirm the situation re immunisation?

[Deleted]

I believe that when the automatic signalling on the Uxbridge branch was renewed in 1994, every track circuit on the line was replaced with jointless track circuits. As a result the Uxbridge branch will be the testbed for the Westinghouse DTG ATO, the Seltrac moving-block ATO, and the site of the battle over the transfer of routes between the District and Piccadilly Lines.

[Tom]

Eastcote to Hillingdon now has WSL FS2500 Jointless Tracks. Rayners Lane is still 33 1/3Hz (I was in the IMR there earlier in the week) and I would expect Uxbridge to be similar.

I' not too sure about what frequency is used at Ruislip Siding, though I'd suspect 33 1/3Hz.

[Deleted]

tom said:

Eastcote to Hillingdon now has WSL FS2500 Jointless Tracks. Rayners Lane is still 33 1/3Hz (I was in the IMR there earlier in the week) and I would expect Uxbridge to be similar.

I' not too sure about what frequency is used at Ruislip Siding, though I'd suspect 33 1/3Hz.

Since it was installed in 1975 I would suspect that it has the same frequency as comparable installations from that era.

[Deleted]

Bit of a bump to an old thread, but related nonetheless.

Uxbridge, Ruislip Sidings and Rayners Lane are all 33 1/3Hz areas. Immunisation of these areas for the new S stock will by done by changing the frequency to 125Hz using motor generators installed by the IMRs. Dual frequency relays will be used, and allow areas to be switched over one at a time. This also applies to Aldgate, and other areas on the east end of the District.

For areas north of Preston Road substation gap, all the way to Amersham, FS2550 JTC will be used, and cut in to existing track circuit wiring for the interim period before full resignalling takes place.

As most of the H&C is currently 125Hz, it will be left alone as far as new stock is concerned, but will eventually be changed over to FS2550.

[Deleted]

not actually true bromley by bow to barking is also 33 1/3hz
dual frequency relays especially the old fish tank westinghouse design do not work in dual areas they are seperate and this has been proven and it does not work and found very worrying problems especially with track relays
and tom as you are the expert on JTC (working on it alot more then me) im sure JTC is supplied at 50hz

[Deleted]

i thought the BTR on the MET was to take out some of the junction at watford south naming the movable angles

[Deleted]

aetearlscourt said:

not actually true bromley by bow to barking is also 33 1/3hz
dual frequency relays especially the old fish tank westinghouse design do not work in dual areas they are seperate and this has been proven and it does not work and found very worrying problems especially with track relays

I never said it wasn't 33 1/3rd, just that some areas are, and some aren't.

I'm aware of the problems with the dual frequency relays, but I'm just going on what I've been told. You know as well as I do, that what you get told and what eventually happens are two very different things.

JTC is supplied 50Hz as far as I know, but there are also conventional track circuits along the Uxbridge branch over pointwork, hence the 33 1/3rd frequency.

As for Watford South Junction, the moveable angles are being removed, and part of the junction is being shifted south towards Moor Park. M63 point machines will be used, unfortunately. The new kiosks and trackside boxes are also slowly being installed.

[Tom]

aetearlscourt said:

and tom as you are the expert on JTC (working on it alot more then me) im sure JTC is supplied at 50hz

It's been a few years since I worked on it now...!

The Tx and Rx units have a 24v DC supply. The PSUs are normally 50Hz, but the ELL and Eastcote to Hillingdon use a special order PSU for a 33 1/3Hz supply.

[slugabed]

To return to the thread,I was always led to believe that the reason the OHLE stops as it does,at St Quintin Park,was that the Westway Flyover bridge,slightly South,didn't have sufficient clearance.True or false? When you ride a WLL train it seems a tight fit.
Slugabed

[roythebus]

Seems unlikely that bridge clearances come into it. When Lillie Road bridge was rebuilt at West Brompton was rebuilt in about 1970, it was raised to Berne loading gauge height. The Westway was built around the same time, so would have to have been built to those clearances as part of the proposed Channel Tunnel route.

A bit of forward thinking for once??

[railtechnician]

Mar 30, 2007 22:06:37 GMT Tom said:

Eastcote to Hillingdon now has WSL FS2500 Jointless Tracks. Rayners Lane is still 33 1/3Hz (I was in the IMR there earlier in the week) and I would expect Uxbridge to be similar.

I' not too sure about what frequency is used at Ruislip Siding, though I'd suspect 33 1/3Hz.

Of course Rayners Lane to North Ealing is presumably all still 33 1/3HZ, it was when I was maintaining it five years ago.

[Tom]

Yes, it's still 33 1/3. Much nicer than 125 -at least the IMRs are quieter!!

[metman]

I thought that which the closing of Neasden and Lotts Road it was all 50? Maybe I'm a bit behind the times!

[mrfs42]

Jan 2, 2009 15:36:17 GMT metman said:

I thought that which the closing of Neasden and Lotts Road it was all 50? Maybe I'm a bit behind the times!

Not power frequencies, but the track circuit frequencies.

[railtechnician]

Dec 19, 2008 19:40:19 GMT Tom said:

Yes, it's still 33 1/3. Much nicer than 125 -at least the IMRs are quieter!!

Yes indeed, on that score my favorite place to do frame maintenance and relay changing was Ealing Broadway IMR, spacious and quiet although in the winter the temperature left something to be desired. In its heyday I imagine Ealing Broadway AET post was a sought after job.

I also liked Ealing Common IMR, a little tight in places but also quiet and nice to test out.

[DWS]

Jan 2, 2009 15:36:17 GMT metman said:

I thought that which the closing of Neasden and Lotts Road it was all 50? Maybe I'm a bit behind the times!

Well you are a metman ;D