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Whatever Goes Wrong, Heat Is Taking the Blame


NX Express

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Excuses, excuses. Eight million New Yorkers, eight million reasons why or why not.

 

But when the sun becomes sweltering and the humidity hovers, it seems as if all manner of transgressions can be explained by a single, conspicuously convenient excuse: it’s too darn hot.

 

When commuter trains in Connecticut broke down this month, officials said extreme heat snarled the system. Some racetracks across the Northeast canceled horse races, citing the heat.

 

False notes at an outdoor concert? Midday nap at the office? An abrupt aversion to skinny jeans?

 

You know what’s to blame.

 

With this month shaping up to be the warmest July on record, the heat has morphed from a meteorological annoyance to a universal scapegoat, blamed for all things even remotely associated with the great, sweaty outdoors.

 

Read more: http://www.nytimes.com/2010/07/26/nyregion/26blame.html?ref=nyregion

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I wish there was A/C in Subway station :) but theres no A/C in the station, just the train :P

 

I'd go for moving AC from train to the stations.

 

As far as everything else, most electronics have an operating range of 45-95 degrees with non-condensing humidity. Train electrical systems can operate to a lot higher temps nominally, but if the cooling systems can't get ahead of the ambient temperature, the hottest parts can go over their safe operating limits.

 

Also, the copper alloy wires can sag from heat, if the (overhead) wires are powering trains, the pantograph can hit a sagging section & pull the wire down or damage the panto, if the wires are on utility poles sag enough they can touch something grounded and cause a short, blacking out or otherwise disrupting activity related to whatever that circuit was powering it.

 

Days in a row of 100 degrees plus temperatures all day long is going to push everything to the brink. The other day, when it was 103, the power lines and other cables suspended from utility & transmission poles and towers were visibly noticeably sagging, lawns everwhere were browning, trees were dropping leaves, tar on roads was sticky vs firm.

 

- A

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I'd go for moving AC from train to the stations.

 

As far as everything else, most electronics have an operating range of 45-95 degrees with non-condensing humidity. Train electrical systems can operate to a lot higher temps nominally, but if the cooling systems can't get ahead of the ambient temperature, the hottest parts can go over their safe operating limits.

 

Also, the copper alloy wires can sag from heat, if the (overhead) wires are powering trains, the pantograph can hit a sagging section & pull the wire down or damage the panto, if the wires are on utility poles sag enough they can touch something grounded and cause a short, blacking out or otherwise disrupting activity related to whatever that circuit was powering it.

 

Days in a row of 100 degrees plus temperatures all day long is going to push everything to the brink. The other day, when it was 103, the power lines and other cables suspended from utility & transmission poles and towers were visibly noticeably sagging, lawns everwhere were browning, trees were dropping leaves, tar on roads was sticky vs firm.

 

- A

 

The subway system was specifically designed to ventilate. There are ventilation shafts throughout the city that disperse heat from the system high in the air, and there are also the street grates designed to allow circulation of fresh air into the system. You cannot run an "outdoor A/C" type system in the subway because the benefit is almost negligible (go stand in 42nd Street/GCT (4)(5)(6) platform 6 hours after 100 degree heat if you don't believe me...the A/C does nothing 10 feet from the unit), and the enormous capital costs with set up and energy costs with running wouldn't be worth it. Plus many trains still create heat when they brake dynamically, and components get hot, so they will just dump hot air in the stations too.

 

Condensers in a/c units also generate enormous amounts of heat which needs to go somewhere, you can't just send it to the street with people there, that would be miserable. If you don't, you're talking about extensive and expensive construction of more ventilation shafts, or you recycle the hot air into the subway system again, which more than offsets any benefit from cooling that an A/C provides within a 5 foot radius.

 

People spend more time in trains in the subway anyway than they do in stations, so the priority has been, correctly, always, to air condition trains rather than stations.

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