Power Loss on trains on the NEC & Keystone Corridor?

[Evan's Trains]

Even though I am a huge railfan I've always wondred what causes "rolling blackouts" on some Amtrak trains that use electric locos. What I mean is when were cruising along and then suddenly all the power is lost the fans stop, the DC Outlets lose power, and the lights flicker or turn off. Is this when catenary dead section ia passed through or something else?

 

[Acela150]

Caternary Dead Sections.. There is no power in that part of the overhead. I think ThirdRail7 could explain more on how the process works. He has tons of knowledge. I'd also like to hear how that process works.

 

[greatcats]

I recall the proper name is a phase gap, an unpowered short section where the power comes from two different sources. I can't be more technical than this description.

 

[Acela150]

Phase gaps IINM are where there is a voltage change. E.g. New Rochelle at CP216 and New Haven.

 

[Hal]

Even though I am a huge railfan I've always wondred what causes "rolling blackouts" on some Amtrak trains that use electric locos. What I mean is when were cruising along and then suddenly all the power is lost the fans stop, the DC Outlets lose power, and the lights flicker or turn off. Is this when catenary dead section ia passed through or something else?

The main circuit breaker has tripped on the locomotive.

Sent from my iPad using Tapatalk

 

[jis]

Phase gaps IINM are where there is a voltage change. E.g. New Rochelle at CP216 and New Haven.

Phase Gap is primarily where the AC Phase powering the two sides of the gap changes, typically found on single phase AC electrification that is fed from commercial three phase power source. The use of the the three phases have to be balanced to make the power companies happy, and this is done by feeding power to consecutive segments from different phases. At a phase gap there might additionally be voltage change etc. Phase gaps may also be used as segment isolation points.

 

[west point]

Phase breaks are some what complicated by what the power source is.

1. New Haven - Boston is sourced as 3 phase primary to CAT source transformers. The current is then supplied to feeder as two phase 25 KV. Whenever train goes from one phase is a phase break.

2. The PRR power is supplied differently. It is similar to the power to your home that is 110 nominal to ground and opposite feeder is also 110 to ground. Combined your home is 220 V nominal leg to leg. The PRR system is identical as it is combined 69 KV to ground and 69 KV to ground. That gives feeder to feeder as 138 KV.phase. PRR era Transformers then dropped voltages to 12 KV for two legs ( Original PRR voltages were 11KV ). So when supply changes from one leg to other need phase break to prevent a 24KV short.

When locos are running they only operate thru phase breaks with one PAN up and have seen engineers lower both PAN approaching the break. Warning for phase breaks were a circle of amber lights on PRR signal. Unknown how on the New Haven -

Boston Amtrak or for NJ Transit.