ABCL vs. AOCL+B

[w0033944]

Just a quick question - I'm familiar with the addition of mini barriers to AOCL crossing in Scotland to convert them to AOCL+B spec, but I'm unsure as to how these crossing differ from existing ABCL types (my excuse is that AHBs and MWLs are more common in my area (with a few of the MCB-OD installations for good measure).

Thanks in advance.

 

[The Planner]

I was always under the impression that AOCL+B were bolt ons to existing AOCL and don't actually get installed as such?

 

[w0033944]

I was always under the impression that AOCL+B were bolt ons to existing AOCL and don't actually get installed as such?

Sorry for the imprecise nature of my question - that's how I understand it as well.

 

[Railsigns]

With the AOCL+B being a 'bolt on' to the existing AOCL circuitry, there are subtle differences in failure modes and how they operate under local control compared to an ABCL, hence the different designations.

 

[w0033944]

With the AOCL+B being a 'bolt on' to the existing AOCL circuitry, there are subtle differences in failure modes and how they operate under local control compared to an ABCL, hence the different designations.

Thanks - as I suspected, the average road user would notice no obvious difference.

 

[Trucker Glen]

The only real difference is whether there are phones.
Most of the existing ABCL crossings have phones and also the 784.1 signs instructing drivers of large and slow vehicles to phone before crossing, like at AHB crossings.
But AOCL+B conversions retain the blue "to contact railway" signs without phones.


Acheilidh No2 level crossing by Inverness Trucker, on Flickr


Hoy level crossing by Inverness Trucker, on Flickr


Although, Halkirk, which was converted from AOCL to ABCL doesn't have phones and got somewhat larger "to contact railway" signs.


Halkirk level crossing by Inverness Trucker, on Flickr