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Question About Operating A SMEE


Maserati7200

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Okay, a car with a SMEE braking system has the brake handle and the power handle. I know that when you out the train in full service brake, you could let go of the deadman's switch. But I noticed that operators have to hold down the brake handle while they are braking it, or else the brake will release. So my question is, when you go into full service brake, and once you are fully stopped let go of the deadman's, if you let go of the brake handle will it stay, or lose brake and then the emergency brake will go on?

 

Also, when a train is terminating, do you simply release the deadman's?

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Okay, a car with a SMEE braking system has the brake handle and the power handle. I know that when you out the train in full service brake, you could let go of the deadman's switch. But I noticed that operators have to hold down the brake handle while they are braking it, or else the brake will release. So my question is, when you go into full service brake, and once you are fully stopped let go of the deadman's, if you let go of the brake handle will it stay, or lose brake and then the emergency brake will go on?

 

Also, when a train is terminating, do you simply release the deadman's?

 

I think that the point of the deadman is to have the device held down at all times; you can't let go of it when you're in motion or the train will stop, period. The NTTs have a deadman somewhere, I don't know if there's a pedal but it most likely may be so since I've never seen anything on the table where the controls are located.

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The NTT's deadman is the master controller. You twist it, it works. Let go, and the train stops.

 

He is talking about the old SMEEs not NTTs. Also all subway cars have the dead man on the master controller since the very first subway train on the IRT. Even the early EL cars, if you let go of the controller, they dumped.

 

On the SMEE cars, the master controller must be held down once the brake is moved past full service into any other position aside from emergency meaning release. If you let go of the master controller when the brakes are not in full service, you dump. The brake handle is not spring loaded and does not need to be held other then when applying or releasing. You can let go of the master controller when the train is still moving as long as you are in full service. I hope this helps a little.

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He is talking about the old SMEEs not NTTs. Also all subway cars have the dead man on the master controller since the very first subway train on the IRT. Even the early EL cars, if you let go of the controller, they dumped.

 

On the SMEE cars, the master controller must be held down once the brake is moved past full service into any other position aside from emergency meaning release. If you let go of the master controller when the brakes are not in full service, you dump. The brake handle is not spring loaded and does not need to be held other then when applying or releasing. You can let go of the master controller when the train is still moving as long as you are in full service. I hope this helps a little.

 

Yeah that answers my question, thanks!

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You can let go of the deadman in full service brake since in that position the train can do nothing but stop (and if it is moving and runs a red, hitting the stop arm will STILL throw the train into emergency) so as far as the train is concerned that is a "safe" situation even if the train is moving.

 

The brake handle will not move from full service with the deadman up. It won't move unless it is moved by an operator, ever. However, if the brake handle is moved out of full service with the deadman up, the train will immediately go into emergency.

 

This is also true when charging a train as when you are doing your standing brake tests you must hold the deadman down or the second you go to anything less than full service, even though you are not moving and there is brake applied, the train will go back into emergency, and you'll have to wait 20 seconds and start over.

 

As for dumping at a terminal, you could let go of the deadman or throw the brake handle into emergency, either way. You have to put the brake handle into emergency anyway to get it out of the valve ("handle off"), so I think it makes more sense to do it that way

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We're instructed to let go in a non-full service position because that's "testing" the deadman for the next person.

There's also "pop & stop", where people take full service and release the handle as the train is still moving (which makes a regular stop without going into emergency), but that's not allowed. When posting, I used to see people do that with 46's from several cars away from the marker, and nail it on spot. But I wouldn't trust it to stop a the right place like that. (Tricky enough when you're in ful control of the handle). But people have it down pact. Yet, it is understandably against the rules.

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We're instructed to let go in a non-full service position because that's "testing" the deadman for the next person.

There's also "pop & stop", where people take full service and release the handle as the train is still moving (which makes a regular stop without going into emergency), but that's not allowed. When posting, I used to see people do that with 46's from several cars away from the marker, and nail it on spot. But I wouldn't trust it to stop a the right place like that. (Tricky enough when you're in ful control of the handle). But people have it down pact. Yet, it is understandably against the rules.

 

Yea, the ole "pop & stop" can lead to flat wheels which will eat the track alive. If flat beat a section of rail long enough, you can get a derailment like the one on CPW a few months ago.

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We're instructed to let go in a non-full service position because that's "testing" the deadman for the next person.

There's also "pop & stop", where people take full service and release the handle as the train is still moving (which makes a regular stop without going into emergency), but that's not allowed. When posting, I used to see people do that with 46's from several cars away from the marker, and nail it on spot. But I wouldn't trust it to stop a the right place like that. (Tricky enough when you're in ful control of the handle). But people have it down pact. Yet, it is understandably against the rules.

 

I've seen operators on both 44's and 46's let the handle go while the train is still moving and perfectly hit the markers, though it hasn't been as far as several car lengths. There is one operator who has been on the same line on the same shift for at least the past 18 months. I've boarded that train at several different stations and I've seen the operator pop the handle about half a car length from the marker every time, and every time, the train's nose is flush with the 10-car marker. I guess he just knows the route really well.

 

Eric, does the "pop & stop" work on the NTT trains?

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I realized "several" was exaggerated. It was way far for my comfort.

It should work on any train. But I don't do that, however there are times I might stop with full service, and not let go, so it would stop the same.

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I realized "several" was exaggerated. It was way far for my comfort.

It should work on any train. But I don't do that, however there are times I might stop with full service, and not let go, so it would stop the same.

 

That doesn't cause flat spots on the wheels if you don't graduate off the brake? Or am I just misinterpreting your statement?

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Yea, the ole "pop & stop" can lead to flat wheels which will eat the track alive. If flat beat a section of rail long enough, you can get a derailment like the one on CPW a few months ago.

 

Full service just gives one maximum brake, not lock up the wheels. Even going into emergency doesn't lock up the wheels. That just cuts power to the motors, then apply all brakes electro-pneumatically. You get no dynamic brakes when going into emergency, in full service you do get maximum dynamic and electro-pneumatic friction braking. In the rain or snow (and when stations is blasting the stations with those power hose washers), is where the wheels do lock up and slide, and flats happen..........

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Full service just gives one maximum brake, not lock up the wheels. Even going into emergency doesn't lock up the wheels. That just cuts power to the motors, then apply all brakes electro-pneumatically. You get no dynamic brakes when going into emergency, in full service you do get maximum dynamic and electro-pneumatic friction braking. In the rain or snow (and when stations is blasting the stations with those power hose washers), is where the wheels do lock up and slide, and flats happen..........

 

Ah ok, I was thinking about older SMEEs that would lock up. My bad.

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I think with the old brake pads, you could get flats. Full service/emergency stops put people on the floor with them, but now, the trains slide a whole lot more..

 

Yea, thats what I was going off of and that is why it is important for transit to have nice round wheels.

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Yea, thats what I was going off of and that is why it is important for transit to have nice round wheels.

 

this is why i never understood why the MTA never did further testing with disk brakes other than the R32's and the R110B's.

 

i know the R32 Pioneer III trucks were a bit of an epic fail, but i still think the MTA should have gone further with testing.

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Disc brakes or not, once the wheel locks up the part that is in contact with the running rail will become flat, this with why the brakes now do not lock up and the train does take longer to stop.

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