Traction Power Substation Fire Stadium-Armory

[srepetsk]

*sigh* http://wmata.com/about_metro/news/Press ... aseID=5972" onclick="window.open(this.href);return false;
They're allowing one train through in each direction at a time and limiting both speed and acceleration through the area.

And are saying it will take SIX MONTHS to rebuild.
Please explain why Metro North can build a substation in a few days.
They could put one good-sized transformer and rectifier on a flatbed trailer and drive it there.

I don't have construction experience, but a month or two doesn't doesn't seem too extraordinary to me (6 though; I think they may be hoping to underpromise and overdeliver). They'll need to get a couple contracts to demo and remove the current/bad transformers (all three are wasted), then clean/repair/rebuild/fix the physical structure, then hope somebody has three 3MW transformers matching their required spec to drop in, wire up, test, verify, and then put into operation.

[farecard]

I don't have construction experience, but a month or two doesn't doesn't seem too extraordinary to me (6 though; I think they may be hoping to underpromise and overdeliver).

My point is they could drop in a temporary one while they rebuild. Even a smaller output substation would help on the line capacity. This is not rocket science; there are flatbeds set up for GV-MV transformer substitution/replacement. I've read FEMA actually keeps such on standby.

While those would be oh-so-wrong transformers for this task, the basic idea is the same.

[Sand Box John]

"farecard"
My point is they could drop in a temporary one while they rebuild. Even a smaller output substation would help on the line capacity. This is not rocket science; there are flatbeds set up for GV-MV transformer substitution/replacement. I've read FEMA actually keeps such on standby.

While those would be oh-so-wrong transformers for this task, the basic idea is the same.

POPCO's primaries in DC are 13.5 KV, said transformer you would need an 850 V output tap. Not exactly off the shelf equipment.

Like I said up the thread, they might be able to make a deal with contractor slated to do Fort Mahan substation upgrade and use one from that project.

[srepetsk]

Like I said up the thread, they might be able to make a deal with contractor slated to do Fort Mahan substation upgrade and use one from that project.

Do you happen to know how many they might have available from that upgrade or others? They'll need to replace all three.

[farecard]

Also note almost the entire rail transit industry [except BART...] uses 750VDC; the source for used transformer & rectifiers is not limited to WMATA.

[Sand Box John]

"srepetsk"
Do you happen to know how many they might have available from that upgrade or others? They'll need to replace all three.

The aerial photo at Goggle shows 3 transformer populating the transformer yard at the Fort Mahan substation. One of them appears to be different then the other 2. Me thinks WMATA will swap out all 3 and replace most or all of the switch gear and cabling in the substation. I say replace most or all of the switch gear because the same document says they intend to upgrade the switch gear to the "standard 6,000 amp capacity profile".

WMATA plans to upgrade 29 substation over the next 6 years.

[dcmike]

Also note almost the entire rail transit industry [except BART...] uses 750VDC; the source for used transformer & rectifiers is not limited to WMATA.

750 is fairly common among streetcar systems, but most of the high-megawatt applications in North America tend to be 600: NYCT, PATH, MBTA, SEPTA, TTC, RTA (Cleveland), CTA, etc.

[JDC]

Metro has a plan to ease congestion due to the ongoing effects of the fire:

During rush hours, Orange and Silver line trains will operate every 8 minutes (vs 6). This will reduce the strain on smaller substations, which Metro asserts are already at capacity. By reducing the headways, Metro claims it will have less trains in service, which will allow it to increase the number of 8-car trains on those lines to counteract the likely increased crowding. http://www.wmata.com/about_metro/news/P ... aseID=5972

[JDC]

Metro has a plan to ease congestion due to the ongoing effects of the fire:

During rush hours, Orange and Silver line trains will operate every 8 minutes (vs 6). This will reduce the strain on smaller substations, which Metro asserts are already at capacity. By reducing the headways, Metro claims it will have less trains in service, which will allow it to increase the number of 8-car trains on those lines to counteract the likely increased crowding. http://www.wmata.com/about_metro/news/P ... aseID=5972

A GGW piece discussing this development: http://greatergreaterwashington.org/pos ... et-slower/

[farecard]

Metro has a plan to ease congestion due to the ongoing effects of the fire:
...
This will reduce the strain on smaller substations, which Metro asserts are already at capacity.

THAT is quite true. Power transformers of that size, cooled with oil, have sizable overload margin, let's say 150% of rated load for 50 minutes......provided you then have maybe 5 hours to cool down the oil afterwards. But that's how WMATA now makes it through an ordinary day. I'm told that many substations are bumping the red line by the end of rush hour.

That's why they've been upgrading both the TPSS's and the WeeZee bonds across the system.

[srepetsk]

Power transformers of that size, cooled with oil, have sizable overload margin, let's say 150% of rated load for 50 minutes......provided you then have maybe 5 hours to cool down the oil afterwards. But that's how WMATA now makes it through an ordinary day. I'm told that many substations are bumping the red line by the end of rush hour.

That's why they've been upgrading both the TPSS's and the WeeZee bonds across the system.

Per the board meeting on Friday, WMATA's substations use a mix of wet and dry transformers. The 3MW one that caught fire was of the dry type. I don't know if that changes anything.

[farecard]

Per the board meeting on Friday, WMATA's substations use a mix of wet and dry transformers. The 3MW one that caught fire was of the dry type. I don't know if that changes anything.

Makes sense, dry transformers have less overload capacity. They are cheaper, however. And they don't need a vault if in a building.

[MCL1981]

Metro has a plan to ease congestion due to the ongoing effects of the fire:

During rush hours, Orange and Silver line trains will operate every 8 minutes (vs 6). This will reduce the strain on smaller substations, which Metro asserts are already at capacity. By reducing the headways, Metro claims it will have less trains in service, which will allow it to increase the number of 8-car trains on those lines to counteract the likely increased crowding. http://www.wmata.com/about_metro/news/P ... aseID=5972

Laughable. As if they ever reliably held to 6 minute headways before this meltdown. The delays in reality have been substantially more than 2 minutes. Typical metro PR garbage.

[JDC]

Metro has updated its workaround plan: Orange and Silver line trains will skip-stop Stadium-Armory station during rush hour; only Blue line trains will service that station. http://www.wmata.com/about_metro/news/P ... aseID=5973

[Sand Box John]

"JDC"
Metro has updated its workaround plan: Orange and Silver line trains will skip-stop Stadium-Armory station during rush hour; only Blue line trains will service that station. http://www.wmata.com/about_metro/news/P ... aseID=5973

The should also consider redeploying the fleet to ban the use of the 5 and 6k cars on that part of the railroad as those cars are the most power hungry.