[Date Prev][Date Next]
[Chronological]
[Thread]
[Top]
RE: (erielack) DL&W single-light signal heads
Does Medium Clear mean proceed at half the speed limit? And does Approach
Medium mean proceed to the next signal at half the speed limit? I don't
fully understand the terminology used in reading signals.
Don Liotta
- -----Original Message-----
From: Wdburt1_@_aol.com [mailto:Wdburt1@aol.com]
Sent: Thursday, July 21, 2011 5:38 PM
To: erielack_@_lists.railfan.net
Subject: (erielack) DL&W single-light signal heads
A single light, same size as all the others, in a round target. US&S
called them an HC-33 marker light, IIRC.
Erie used them in a variety of applications, most commonly on three-headed
interlocking home signals that displayed only aspects where the bottom or
top signal head was always red. Take a look at photos of Marion or other
complicated places and you'll see a few of those.
Erie never (so far as I know) accepted the idea of using a dark signal head
as part of a signal aspect. A dark light was to be interpreted in the
most restrictive manner possible. The DL&W did allow it, and made
extensive
use of darkened signal heads to convey various aspects. For instance, some
signals on the Scranton and Buffalo Divisions were set up with the marker
light below a standard, three-light color light signal head. The upper
head
could display red, yellow, and green. If the upper head displayed yellow
and the marker light came on displaying green, that changed the indication
from Approach to Approach Medium. As you DL&W guys probably know, the
railroad also made extensive use of two-over-two configured signals where
the
green light was on the bottom. Some of these were used at interlockings.
In that application the only thing needed to convey Stop was a red light
burning in the upper signal head. Add a green light below it, and you got
Medium Clear. This configuration was also used in some wayside signals to
provide Approach Medium as discussed above. In that case one of the two
lights in the lower target usually would be blanked out.
The Erie Lackawanna Mailing List
http://EL-List.railfan.net/
To Unsubscribe: http://Lists.Railfan.net/erielackunsub.html
The Erie Lackawanna Mailing List
http://EL-List.railfan.net/
To Unsubscribe: http://Lists.Railfan.net/erielackunsub.html
------------------------------