Drivers Reminder Appliance (DRA) How it works.

[XCTurbostar]

Hi all,

In modern units (Class 387, 700, 172, 222 & 170) how does the drivers reminder appliance work? I have a few key questions;

• When stationary; What key items does the DRA disable? Does the engine still rev? can the reverser still be moved?
  
• When in motion; Are the emergency brakes applied? is this locked or can the brake application be overruled (like TPWS) If the DRA is disengaged after being applied will the brakes stop being applied or continue until stopped?
  
• What is the process when the train has returned to a stand and the DRA disengaged? Can power be applied straight away or does the reverser or brake need to be in a certain setting?

Thanks,
Ross

 

[neilb62]

Hi all,

In modern units (Class 387, 700, 172, 222 & 170) how does the drivers reminder appliance work? I have a few key questions;

• When stationary; What key items does the DRA disable? Does the engine still rev? can the reverser still be moved?
  
• When in motion; Are the emergency brakes applied? is this locked or can the brake application be overruled (like TPWS) If the DRA is disengaged after being applied will the brakes stop being applied or continue until stopped?
  
• What is the process when the train has returned to a stand and the DRA disengaged? Can power be applied straight away or does the reverser or brake need to be in a certain setting?

Thanks,
Ross

Can only speak for 221's and 390's but basically pressing the DRA prevents traction power being taken, yes the reverser can still be moved but the engines (221) don't rev.

No, the brakes are not applied, it acts independently of the brake and reverser circuits.

When no longer needed the DRA is simply disengaged and power taken as usual, on ours should you try to take power with the DRA set you will get a TMS warning.

 

[D365]

If you want the shortest possible answer, as above, the DRA simply prevents traction being taken.

 

[westcoaster]

Depending on the unit if you press the DRA while braking, it will knock out the rheostatic braking and just use straight air.

 

[Jd12]

In a class 220/221 the DRA simply stops you from taking traction, it'll let you put it into forward and it'll rev the engines up, the brakes will release if you put the throttle into traction it just won't move. Unless you roll cause the brakes have released obviously..

 

[najaB]

In modern units (Class 387, 700, 172, 222 & 170) how does the drivers reminder appliance work? I have a few key

I take it you've seen this video?

[youtube]JuIM6N6LCzY[/youtube]

 

[455driver]

Are the emergency brakes applied? is this locked or can the brake application be overruled (like TPWS) If the DRA is disengaged after being applied will the brakes stop being applied or continue until stopped?

Once a TPWS brake application happens the train is stopping, it cannot be overruled.

As for DRA it depends on the stock, most it just prevents power being taken and others it applies the brakes.

 

[Kneedown]

There are two types of DRA which we have had on our units (CT/EMT)
The most common is the "Passive" version, which is manually applied and merely prevents the unit obtaining power if an attempt is made to so with the DRA applied.
The second is the "Pro-active" which was fitted to the ex MML 170's (170/1) which automatically applies if the doors are released and the previous AWS was a caution. It would be released by applying, and deactivating the DRA button.

 

[whoosh]

Pro-active version also on Class 222s

 

[XCTurbostar]

I take it you've seen this video?

I have seen this video but I wanted to know if newer units had a modernised system. From most of the posts here, it appears that it hasn't changed!

Thanks,
Ross

 

[t_star2001uk]

168/0 used to be fitted with the active DRA but it was replaced with the passive type later.

 

[XCTurbostar]

If the Power is on and the DRA is pressed in motion. The train obviously cuts power to an idle/coast. If the DRA is then turned off, does the train then start accelerating or does another notch have to be selected first?

Thanks,
Ross

 

[headshot119]

Arriva Bubble Car (121032) the DRA cut power to the gear controller, you could rev the nuts off of the engines, and get the brakes off, but you couldn't apply power as it wasn't in gear.

 

[GW43125]

If the Power is on and the DRA is pressed in motion. The train obviously cuts power to an idle/coast. If the DRA is then turned off, does the train then start accelerating or does another notch have to be selected first?

Thanks,
Ross

I think it varies from class to class. I'm sure there are some where turning off the DRA will let the power come back immediately, but there are certainly others which require you to shut off and take power again after taking off the DRA.

 

[physics34]

Operating the DRA whilst braking on a class 377, cuts out the rheostatic brake and switches on the friction braking instead.

 

[Kneedown]

Operating the DRA whilst braking on a class 377, cuts out the rheostatic brake and switches on the friction braking instead.

Was the same on 323's, to the extent that CT issued an instruction that the DRA was not to be operated on the move on 323's due to reduced braking effect.

 

[physics34]

Was the same on 323's, to the extent that CT issued an instruction that the DRA was not to be operated on the move on 323's due to reduced braking effect.

yep thats what we have in place on Southern too

 

[edwin_m]

I was involved with the original studies that came up with the idea of the DRA.

It was never intended to be used on the move, only when at a station stop with the starter signal at danger. This is the situation that poses the most severe risk of starting-away SPADs, and using it at other times arguably undermines the safety benefit.

It appears from the above that some TOCs may be mandating its use in other situations. Is this so?

 

[bengley]

I was involved with the original studies that came up with the idea of the DRA.

It was never intended to be used on the move, only when at a station stop with the starter signal at danger. This is the situation that poses the most severe risk of starting-away SPADs, and using it at other times arguably undermines the safety benefit.

It appears from the above that some TOCs may be mandating its use in other situations. Is this so?

Nothing to do with TOCs, it's in the rule book.

 

[edwin_m]

Nothing to do with TOCs, it's in the rule book.

Thanks for that.

It states the DRA must be used when stopped at a signal at danger. Away from a platform I'd suggest there was little safety benefit in doing so, as the signal is the only reason the train would stop there. However it's probably not a major safety disbenefit.

It also states that DRA can be set before the train stops, but only when there is no signal at the end of the platform, which seems like a drafting error as if there is merit in doing this then it would apply whether the signal was at the platform end or somewhere beyond. On trains where the DRA affects how the brakes work then it sounds like a bad idea to use it with the train in motion.

Finally it doesn't actually say these are the only circumstances the DRA should be used, so it still leaves scope for TOCs to require its use in other situations.

 

[BestWestern]

Thanks for that.

It states the DRA must be used when stopped at a signal at danger. Away from a platform I'd suggest there was little safety benefit in doing so, as the signal is the only reason the train would stop there. However it's probably not a major safety disbenefit.

It also states that DRA can be set before the train stops, but only when there is no signal at the end of the platform, which seems like a drafting error as if there is merit in doing this then it would apply whether the signal was at the platform end or somewhere beyond. On trains where the DRA affects how the brakes work then it sounds like a bad idea to use it with the train in motion.

Finally it doesn't actually say these are the only circumstances the DRA should be used, so it still leaves scope for TOCs to require its use in other situations.

As ever, the privatised railway takes a single, simple instruction and turns it into War & Peace, with a slightly different version for each TOC depending on the colour of the Managing Director's underpants on a tuesday...

 

[island]

Wasn't the whole point of the DRA to stop ding ding and aways?

Using it for braking/to stop a moving train seems to miss that point a tad.

 

[Domh245]

Wasn't the whole point of the DRA to stop ding ding and aways?

Using it for braking/to stop a moving train seems to miss that point a tad.

You are correct on the first point. As for the second point, impression that I've gained from reading this thread is that the DRA is (was) used by some drivers as a convenient traction cut out switch (which it sort of is) - usually to cut out the rheostatic braking for whatever reason (if you look at the recent piccadilly line problems, the change over from friction to rheostatic braking is one mentioned source of wheel flats - it is possible that it is a similar case here). They aren't using it to actually stop the train

 

[ComUtoR]

As for the second point, impression that I've gained from reading this thread is that the DRA is (was) used by some drivers as a convenient traction cut out switch (which it sort of is) - usually to cut out the rheostatic braking for whatever reason

Using it for braking/to stop a moving train seems to miss that point a tad.

Its not being used for braking or to deliberately to switch the braking over. The rheo dropping out is a consequence of setting the DRA. The rheo will also drop out when a unit gaps.

 

[Nym]

You are correct on the first point. As for the second point, impression that I've gained from reading this thread is that the DRA is (was) used by some drivers as a convenient traction cut out switch (which it sort of is) - usually to cut out the rheostatic braking for whatever reason (if you look at the recent piccadilly line problems, the change over from friction to rheostatic braking is one mentioned source of wheel flats - it is possible that it is a similar case here). They aren't using it to actually stop the train

Could easily be solved on the Piccadilly Line by permanently cutting out Rehostatic braking for the season...

 

[axlecounter]

I thought that the DRA was to be set immediately after passing a yellow aspect, or at least this is what seemed logic to me, since from there on any distraction could make a driver forget about the signal at danger and consequently about setting the DRA...

 

[ComUtoR]

It also states that DRA can be set before the train stops, but only when there is no signal at the end of the platform

I can't see any but or only. Under 10.2 and 10.3 it allows for the DRA to be set before the train stops at a platform.

The friction kicks in pretty quick in any case. It also states may set and at my TOC we are not allowed to stick it in on the move. The unit must come to a stand first.

 

[455driver]

I thought that the DRA was to be set immediately after passing a yellow aspect, or at least this is what seemed logic to me, since from there on any distraction could make a driver forget about the signal at danger and consequently about setting the DRA...

I can think of at least three locations that if you were to set the DRA as you pass the yellow you wont get within half a mile of the red before the train comes to a stand so that wont work, logic doesnt beat physics!

 

[Mintona]

On the trains I drive, if I set the DRA on the move I will have an emergency brake application; however this isn't typical, and is a result of a secondary safety system on board.

 

[edwin_m]

I thought that the DRA was to be set immediately after passing a yellow aspect, or at least this is what seemed logic to me, since from there on any distraction could make a driver forget about the signal at danger and consequently about setting the DRA...

But then if the driver needs to take power to get up to the red they will have to unset the DRA. This is an obvious SPAD trap.