Joined: 05/07/2020(UTC) Posts: 326 Location: Mississippi, Vancleave
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While watching some videos of British trains, I see double electric engines in push/pull service. The engines all have their pantographs (8 in all) up running on the wire. Is this standard practice. In the U.S. only the rear pantograph is used. Reason is: If the front pantograph snags the wire, it would take out the rear pantograph leaving the engine without power.
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Joined: 04/02/2011(UTC) Posts: 3,563 Location: Paris, France
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Hi Ron In France only one pantograph is raised on any loco or consist (TGV, Z50000, etc) The only exception is in low voltage zones (1500VDC) 2 pantographs are raised to cope with high start currents, until a medium speed is reached (not needed with 25000 VAC) Cheers Jean |
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 5 users liked this useful post by JohnjeanB
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Joined: 08/11/2001(UTC) Posts: 47 Location: Oppegård,
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When two (or more) loks are pulling the train, each lok will have ONE pantograph raised.
Regards Tor Harald Bøhler |
Tor Harald Bøhler Oppegård, Norway |
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Joined: 16/02/2004(UTC) Posts: 15,443 Location: DE-NW
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Originally Posted by: torhb  When two (or more) loks are pulling the train, each lok will have ONE pantograph raised. Nope.   |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS  |
 4 users liked this useful post by H0
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Joined: 21/05/2004(UTC) Posts: 1,768 Location: Brisbane, Queensland
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Originally Posted by: H0  Originally Posted by: torhb  When two (or more) loks are pulling the train, each lok will have ONE pantograph raised. Nope. It needs to be pointed out here that it would also depend on the time period. With the modern spar type pantographs that have two contact points I believe Tor is correct. However with the earlier SBS 9 single bar style pantographs you see from epocheIII etc then I they would normally run with both pantographs raised as per Toms photo. |
modelling era IIIa (1951-1955) Germany |
 1 user liked this useful post by applor
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Joined: 16/02/2004(UTC) Posts: 15,443 Location: DE-NW
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Originally Posted by: applor  It needs to be pointed out here that it would also depend on the time period. With the modern spar type pantographs that have two contact points I believe Tor is correct. I think it also depends on the region. Netherlands have low voltage and therefore high amps, so sometimes a single loco will use both pantographs. Tor may be theoretically correct, but sometimes train drivers simply forget to lower a pantograph. In case of ice on the catenary, both pantographs may also go up. So it also depends on the season and the weather conditions. Maximum speed of the consist depends on the pantographs that have been raised. For maximum speed, as few pantographs as possible will be raised with as much spacing between them as possible. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS  |
 1 user liked this useful post by H0
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Joined: 26/07/2021(UTC) Posts: 635 Location: Sydney
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Copied from various sources: 4 pantographs used per train set, 8 carriages. Australia, Sydney, Waratah train sets 78 in total, 8 carriages per set, as long as the train can be to fit in all the city stations. The network is 1500v DC conductor rated at 2000amps. Not a limitation in the city, but it is up the Blue Mountains west of Sydney which is an issue. But we are stuck with 1500v DC, far too complex to change the city network. Sydney Trains EMUs are actually in two car blocks when it comes to power. Each pantograph powers each two car block under normal circumstances, which means each pantograph powers 4 traction motors, one air compressor some sort of alternator to supply 120v, 240v, and 480v to various systems. The two car blocks can get a remote feed from a neighbouring alternator, but when a pantograph is down, the traction motors in that 2 car block are not provided with power.  More reading material here: Electrification of the Sydney Suburban Train Network https://dictionaryofsydn...y_suburban_train_network
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 3 users liked this useful post by Toosmall
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Joined: 26/07/2021(UTC) Posts: 635 Location: Sydney
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A couple of photos I took at Artarmon station Sydney. The 4 pantographs are used (shot through very dence wire fencing also above head).  
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 1 user liked this useful post by Toosmall
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Joined: 05/07/2020(UTC) Posts: 326 Location: Mississippi, Vancleave
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Probably the answer is: The train will use as many pantographs as needed to power all the blocks.
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Joined: 26/07/2021(UTC) Posts: 635 Location: Sydney
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Not only are the Sydney trains using 4 pantographs. There are dual wires. 
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 3 users liked this useful post by Toosmall
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Joined: 16/02/2004(UTC) Posts: 15,443 Location: DE-NW
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Originally Posted by: Toosmall  Not only are the Sydney trains using 4 pantographs. There are dual wires. I've seen dual wires in Belgium, too. At low voltages (1500 V, 3000 V), you need many amps to get 6 MW power. |
Regards Tom --- "In all of the gauges, we particularly emphasize a high level of quality, the best possible fidelity to the prototype, and absolute precision. You will see that in all of our products." (from Märklin New Items Brochure 2015, page 1) ROFLBTCUTS  |
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