Railroad Forums 

  • SLV and IV in the same Consist?

  • Discussion relating to Southeastern Pennsylvania Transportation Authority (Philadelphia Metro Area). Official web site can be found here: www.septa.com. Also including discussion related to the PATCO Speedline rapid transit operated by Delaware River Port Authority. Official web site can be found here: http://www.ridepatco.org/.
Discussion relating to Southeastern Pennsylvania Transportation Authority (Philadelphia Metro Area). Official web site can be found here: www.septa.com. Also including discussion related to the PATCO Speedline rapid transit operated by Delaware River Port Authority. Official web site can be found here: http://www.ridepatco.org/.

Moderator: AlexC

 #1353656  by 34thStreet
 
As I was walking down Market St. today I noticed a train heading into 30th Street that had 3 Silverliner V cars on the front, with two Silverliner IV's trailing. I've never seen this before, is it normal to couple the different sets together? How do the various systems on the trains differ or are they similar, (i.e. doors, announcements, lights, HVAC, etc)?
 #1353781  by R36 Combine Coach
 
I recall a video somewhere of a mixed consist some time ago. Too bad today's transportation agencies don't make everything compatible (as the LIRR did for anything from MP54 to MP75). At least the Budd (II), St. Louis (III) and GE (IV) Silverliners were indeed interchangeable and compatible (not sure if the Pioneer III was).
 #1353785  by zebrasepta
 
R36 Combine Coach wrote:I recall a video somewhere of a mixed consist some time ago. Too bad today's transportation agencies don't make everything compatible (as the LIRR did for anything from MP54 to MP75). At least the Budd (II), St. Louis (III) and GE (IV) Silverliners were indeed interchangeable and compatible (not sure if the Pioneer III was).
A bit off topic but
doesn't NJT mix their comets with the Comet V being the cab car?
 #1353788  by jackintosh11
 
zebrasepta wrote:
R36 Combine Coach wrote:I recall a video somewhere of a mixed consist some time ago. Too bad today's transportation agencies don't make everything compatible (as the LIRR did for anything from MP54 to MP75). At least the Budd (II), St. Louis (III) and GE (IV) Silverliners were indeed interchangeable and compatible (not sure if the Pioneer III was).
A bit off topic but
doesn't NJT mix their comets with the Comet V being the cab car?
Yes, and they only use Comet V cabs unless it is absolutely necessary to use a Comet IV cab. Comet II cabs don't exist anymore. Comets are never mixed with multilevels.
 #1353792  by F-line to Dudley via Park
 
jackintosh11 wrote:
zebrasepta wrote:
R36 Combine Coach wrote:I recall a video somewhere of a mixed consist some time ago. Too bad today's transportation agencies don't make everything compatible (as the LIRR did for anything from MP54 to MP75). At least the Budd (II), St. Louis (III) and GE (IV) Silverliners were indeed interchangeable and compatible (not sure if the Pioneer III was).
A bit off topic but
doesn't NJT mix their comets with the Comet V being the cab car?
Yes, and they only use Comet V cabs unless it is absolutely necessary to use a Comet IV cab. Comet II cabs don't exist anymore. Comets are never mixed with multilevels.
Coaches vs. MU's intermixing is apples/oranges in the extreme. Usually any types of coaches are fair game for intermixing because HEP cabling is a pretty 'dumb' data stream that doesn't care what it's passing through. NJT is an outlier the way it segregates MLV's from Comets.

MU's have to balance the whole consist's propulsion and have much more 'talky' interconnections between cars. The more different the makes/models of MU's you're intermixing, the harder it is to keep them in-sync. Until ultimately it just starts degrading the consist's performance. SLV's being AC traction and the previous gens all being DC traction is a dramatic enough technological difference that it'd be fighting a losing battle in design of the MU'ing connections to square up all the differences in how the propulsion systems behave. So they don't even try. Very few systems even bother trying making their AC and older DC traction units trainline; it's just better to make a clean break, especially with nearly everything worldwide gradually flipping over to AC motors going forward. If anything has to be made compatible, let it be AC propulsion with other AC propulsion.
 #1354000  by ex Budd man
 
F-line to Dudley via Park wrote:
jackintosh11 wrote:
zebrasepta wrote:
R36 Combine Coach wrote:I recall a video somewhere of a mixed consist some time ago. Too bad today's transportation agencies don't make everything compatible (as the LIRR did for anything from MP54 to MP75). At least the Budd (II), St. Louis (III) and GE (IV) Silverliners were indeed interchangeable and compatible (not sure if the Pioneer III was).
A bit off topic but
doesn't NJT mix their comets with the Comet V being the cab car?
Yes, and they only use Comet V cabs unless it is absolutely necessary to use a Comet IV cab. Comet II cabs don't exist anymore. Comets are never mixed with multilevels.
Coaches vs. MU's intermixing is apples/oranges in the extreme. Usually any types of coaches are fair game for intermixing because HEP cabling is a pretty 'dumb' data stream that doesn't care what it's passing through. NJT is an outlier the way it segregates MLV's from Comets.

MU's have to balance the whole consist's propulsion and have much more 'talky' interconnections between cars. The more different the makes/models of MU's you're intermixing, the harder it is to keep them in-sync. Until ultimately it just starts degrading the consist's performance. SLV's being AC traction and the previous gens all being DC traction is a dramatic enough technological difference that it'd be fighting a losing battle in design of the MU'ing connections to square up all the differences in how the propulsion systems behave. So they don't even try. Very few systems even bother trying making their AC and older DC traction units trainline; it's just better to make a clean break, especially with nearly everything worldwide gradually flipping over to AC motors going forward. If anything has to be made compatible, let it be AC propulsion with other AC propulsion.
Running the SL-IIs & IIIs with the SL-IVs presented their own problems. Acceleration and braking rates were different causing buffing /drafting issues even between the IIs and IIIs. At one time mixed consists were banned. The Pioneers were incompatible, knuckle couplers and 27 pin jumpers verses spear couplers and electric heads. Indeed, the spear couplers and electric heads were retrofitted to the IIs and IIIs after the GEs came onto the property.