ST9604-CS 980224 HLIITFCX_)LI (S
Huitt-Zollars, Inc. / 3131 McKinney Avenue t Suite 600 / LB 105 / Dallas, Texas 75204-2489 / 214/871-3311 / FAX 214/871-0757
February 24, 1998
Mr. Kenneth M. Griffin, P.E. ~
Director of Engineering / Public Works "-
City of Coppell
255 Parkway Boulevard
Coppell, Texas 75019
..... ,RzE!"~~ at Belt Line Road
Dear Mr. Griffin:
Attached is a copy of a memo sent from Railroad Controls Limited to Jan Seidner at
DART listing some additional "General Notes" which need to be added to the Railroad
Preemption plan, Sheet S-3. Please have your signal personnel review the notes and
provide us with any additional comments.
Please feel free to call if you have any questions.
Sincerely,
HUITT-ZOLLARS, INC.
Kenneth A. Roberts, P.E.
Vice President
1 :\PRO J\01227901 \RRSIG. DOC
Dallas / Fort Worth / Houston / El Paso / Phoenix / Tustin / Ontario / Albuquerque
FEB-iS-1998 12:~9 COMMUTER RAIL (T~E) 214 ?49 3~S09 P.O1
Fax Transmission
COMMUTER RAIL & RAILROAD MANAGEMENT
Dallas Area Rapid Transit P. O. Box 660163
Dallas, Texas 7526SJ210
Voice (2t4) 749-2917
FAX (214) 749-3609
No. of pages (incl. this one):~. ~ ..
Date:
To: BILL BROWN
2-19-98
From: JAN SEJDNER
Fax number: ~ ~7 L '~ 0 ~. 5 ~_ Voice: .......
FAX, SAM - 04/24/1995
12:49 COMMUTER RAIL (T~E:, 214 ?49 3609 P.B2
FAX MEMORANDUM
To: Jan Seidner I DART
Fax Phone: 2(4-749-2809
Voice Phone: 244-749491 ?
From: Rick Campbell
Fax Phone: 817-626-3111
Voice Phone: 817-426-2050
Distribution: Jet Martin / FWWR
Date: 02/06/98
/ie Pages inol, Hover:. 2
liE: Fairway Drive / Coppall, TX
Jan:
Per our telephone conversatior: regarding 1he above referenced project, I have
bibwinG comments t~ add to the franc signal notes. ,
The following General Notes should be added to the operation of the railroad
preemi:rUort as detailed oft sheet S-3.
1 - The IrafRo s~gnel controller shah be equipped to receive two inputs from the railroad
signal controls. Both inputs will be maintained in a normally Closed state when no trains
are present. Upon approach of a train, the first Enput (Railroad Preempt) will open and
initiate the preemption sequence. The preemption sequence wilt proceed to the
beginning of Track Clearance Green, There, the preemption uHquence will stop timing
at the begtnnir~ of track deamnc4e greer~ until the second input (Gate Down) opens.
~ce open, the preemption sequence will proceed normally with the t~ming of Track
Clearance Green as described.
2 - The traffic ,T~nal controller shaft monitor the Railroad PreernDt input (#1 } for
When active (open circuit), a maximum ;reemption timer shall I:e~in timing. This timer
sha|l have a minimum range of 1 to 30 rnin4jtes. !f the timer exl:)S as a remJ/t of
continuous actjrvity, the preemption gmitecl sequence interval shall terminate through
normal deararr..,es 1~ the ag red state and Nt Red 'Soft Flash" shall begin. The
contJ'oiler shah rema(n ~n ~is state until the Railroad Preempt input (#1) returns to the
inactive state (dosed circuit).
3 - The traffic signal controller Supplier shah be required to demonstrate the proper
operation of the preemption inlNJts prior to pJacing the traffic signals in operation.
~EB-~9-1990 12:50 COMMUTER RAIL (TRE] 214 949 3809 P.03
~hee{ S-3 a~ Note 3, Existing notes 3 through 7 shall be tenumbered accordingly.
3. Stop Timing at the beginning of Phase 8 Green until me Gate Down input is
received from the railroad ,~3nal controls.
Finally, I will provide 25 seconds of Advance Preemption calculated as lotlows:
Pedestrian Clearance- 15 Sends {60' {~4'Isec.)
Yellow Change - 4.0 Seconds
Red Clearance - 2.0 Seconds
Track Clearance Green Prior to Activation Railroad Signals - 4.0 Seconds
The City should review this value and indicate their concurrerr, e.
TDTAL P.03