NCE Powercab Question

[Bill37]

Hi,

I currently use a Hornby Elite but having problems with the programming/address system so considering the Powercab starter set as a replacement.

Question is, I have read somewhere that it doesn't have any "protection" - does this mean if a loco derails and causes a short circuit will it brick the powercab?

 

TIA

 

Bill.

[AndrueC]

No. It does have protection. However it (or rather the PSU) only cuts the power briefly before automatically restoring it. I would imagine that if you did nothing about the short for long enough something would give. I own a PowerCab and the only warning you get is a relatively quiet buzzing as the power is cut then restored many times a second.

 

I installed a separate circuit breaker (a PSX-AR) that cuts the power and screams its head off. Most important it requires manual resetting.

Edited January 2, 2022 by AndrueC

[Ron Ron Ron]

From NCE

 

"You MUST use some form of Protection!

All NCE systems and boosters have built in over current sensing for basic self-protection that will continuously / automatically try to reset every half second (500ms) until the unit is damaged.

They do not have manual breakers that will trip or fuses that will blow.  

Use the new EB1 v1.1 electronic circuit breaker to protect the Power Cab against short circuits."

 

"The DCC circuit breakers will isolate any short circuit and protect the PowerCab from over heating when there is a short circuit".

 

 

 

.

 

[Kaput]

If your only issues with the Elite are around programming then it might be worth considering a Sprog and using DecoderPro on your PC to do all your programming and keep the elite solely for running.

[dpgibbons]

Supplying a controller that requires an extra GBP30 purchase to prevent it from self-harming is bizarre. The reports of Powercabs melting put me off buying one.  

 

3 hours ago, Ron Ron Ron said:

From NCE

 

"You MUST use some form of Protection!

All NCE systems and boosters have built in over current sensing for basic self-protection that will continuously / automatically try to reset every half second (500ms) until the unit is damaged.

They do not have manual breakers that will trip or fuses that will blow.  

Use the new EB1 v1.1 electronic circuit breaker to protect the Power Cab against short circuits."

 

"The DCC circuit breakers will isolate any short circuit and protect the PowerCab from over heating when there is a short circuit".

 

 

 

.

 

 

[Nigelcliffe]

8 hours ago, Kaput said:

If your only issues with the Elite are around programming then it might be worth considering a Sprog and using DecoderPro on your PC to do all your programming and keep the elite solely for running.

 

Or, even cheaper, a USB cable:  connect the Elite from it's USB socket to the PC and use DecoderPro....   

Unless there's a problem with the programming on the Elite's hardware  (There may be, it might be really slow via the computer link, its so long since I touched an Elite that I can't remember ). 

 

 

The PowerCab relies on either having down-stream protection, or the Power Supply cutting out to protect things.  Consequently, don't pick a power supply for the PowerCab which is "over powerful" - get one which delivers exactly the volts/amps recommended, not "more to be on the safe side", because that "more" is now "potentially destructive". 

 

 

- Nigel

[Lemmy282]

Had a couple of Powercabs for over ten years, never had a problem so long as the supplied power brick is used. There have been a few derailments, but never left long enough to cause a problem.

A few years ago I did install MERG district cutouts just to be on the safe side though!

 

Nigel L

[AndrueC]

Resets every 500ms? I wonder then what the buzzing was I used to get. Not that I ever had many shorts anyway but I'm sure something buzzed.

[BromsMods]

17 hours ago, AndrueC said:

I installed a separate circuit breaker (a PSX-AR) that cuts the power and screams its head off. Most important it requires manual resetting.

 

Just to clarify, the PSX-AR is for use where a loop of track requires an auto-reverser to prevent short circuits.  For straightforward short circuit protection the PSX-1 is an excellent piece of equipment and has a sufficiently low cutout setting to protect the Powercab. On my PowerPro 5a system I use a PSX-4 which provides protection for 4 track power outlets; this helps to simplify short circuit detection on a large layout as well as provide the protection required.

[AndrueC]

14 minutes ago, BromsMods said:

 

Just to clarify, the PSX-AR is for use where a loop of track requires an auto-reverser to prevent short circuits.  For straightforward short circuit protection the PSX-1 is an excellent piece of equipment and has a sufficiently low cutout setting to protect the Powercab. On my PowerPro 5a system I use a PSX-4 which provides protection for 4 track power outlets; this helps to simplify short circuit detection on a large layout as well as provide the protection required.

A very good point. What range of current protection does it offer? The PSX-AR only offers one level of protection suitable for a basic PowerCab which is 1.2A, quite a bit below what the PowerCab can handle. The other trip values are too large.

Edited January 3, 2022 by AndrueC

[BromsMods]

From the manual:

 

Wide Range of Current Trip Setting: The breaker trip current can be adjusted over a range of 1.27 to 10.2 amperes. With additional cooling, the PSX can handle up to 19.1 amperes. Trip current values are selected by setting a CV. Certain selected values can be set by placing jumpers on the board. Default trip current is about 4 amperes, which will work correctly for most layouts.

 

J6 – Sets the current trip level. When CV49=00 [default] the trip current is 3.81 amperes if no jumpers are installed. If J6-2 is connected to J6-1 and J6-4 to J6-3 is open, then the current trip is 1.27 amperes. This is the correct setting for the NCE Power Cab. If J6-4 is connected to J6-3 and J6-2 to J6-1 is open, then the current trip is 6.35 amperes. If J6-4 is connected to J6-3 and J6-2 is connected to J6-1, then the current trip is 8.89 amperes.

 

[AndrueC]

Ah, so that's the same - thought it probably would be. 1.27A is of course still enough to run quite a lot of trains but it's a shame there isn't a setting closer to 2A.

[Dungrange]

4 hours ago, AndrueC said:

Ah, so that's the same - thought it probably would be. 1.27A is of course still enough to run quite a lot of trains but it's a shame there isn't a setting closer to 2A.

 

But you'd only use the PSX on the track power bus.  If you have a separate accessory bus which is connected on the Powercab side of the PSX, then you'd have 1.27A for the trains plus still have up to 0.73A for your accessories and a 2A Powercab can't supply any more power.

[steve45]

On 03/01/2022 at 21:11, Dungrange said:

 

But you'd only use the PSX on the track power bus.  If you have a separate accessory bus which is connected on the Powercab side of the PSX, then you'd have 1.27A for the trains plus still have up to 0.73A for your accessories and a 2A Powercab can't supply any more power.

This might be a stupid question so forgive me if it is, but don't you need short circuit protection on the accessory bus as well?

[Dungrange]

1 hour ago, steve45 said:

don't you need short circuit protection on the accessory bus as well?

 

You can add short circuit protection to the accessory bus if you want to, but what will cause the short on the accessory bus?  The main causes of a short are derailments or by running into a set of points that are incorrectly set.  Therefore, ideally you want the short circuit protection to shut down the track bus, whilst still leaving power to operate accessories (ie throw a set of points to remove the short).  However, there is no reason why you couldn't add a second PSX on your accessory bus.

Edited January 23, 2022 by Dungrange

[steve45]

5 minutes ago, Dungrange said:

 

You can add short circuit protection to the accessory bus if you want to, but what will cause the short on the accessory bus?  The main causes of a short are derailments or by running into a set of points that are incorrectly set.  Therefore, ideally you want the short circuit protection to shut down the track bus, whilst still leaving power to operate accessories (ie throw a set of points to remove the short).  However, there is no reason why you couldn't add a second PSX on your accessory bus.

 

 

 

 

Thanks for your very informative reply, I suppose as long as you are careful wiring in the accessories in the first place then there should be no need for short circuit protection. I presume you can still throw the point using the Procab throttle as the PSX has shut down on the track power bus only, so the accessory bus is still powered and working?

 

Regards

 

Steve

[Dungrange]

1 minute ago, steve45 said:

I presume you can still throw the point using the Procab throttle as the PSX has shut down on the track power bus only, so the accessory bus is still powered and working?

Yes.  The PSX would shut down all power to the track, but the PowerCab (or any other command station) would still be able to operate anything on the accessory bus.  Of course that only works if you have separate track and accessory buses.

[steve45]

On 03/01/2022 at 15:46, BromsMods said:

From the manual:

 

Wide Range of Current Trip Setting: The breaker trip current can be adjusted over a range of 1.27 to 10.2 amperes. With additional cooling, the PSX can handle up to 19.1 amperes. Trip current values are selected by setting a CV. Certain selected values can be set by placing jumpers on the board. Default trip current is about 4 amperes, which will work correctly for most layouts.

 

J6 – Sets the current trip level. When CV49=00 [default] the trip current is 3.81 amperes if no jumpers are installed. If J6-2 is connected to J6-1 and J6-4 to J6-3 is open, then the current trip is 1.27 amperes. This is the correct setting for the NCE Power Cab. If J6-4 is connected to J6-3 and J6-2 to J6-1 is open, then the current trip is 6.35 amperes. If J6-4 is connected to J6-3 and J6-2 is connected to J6-1, then the current trip is 8.89 amperes.

 

Hi John,

 

If you personally use a PSX for power protection then it comes highly commended, I have just ordered one for my Powercab and I have read the instructions online.

 

Am I correct in thinking you don't need to program the PSX at all if you simply connect a jumper from J6-2 to J6-1 to obtain 1.27 amperes or is there another reason why I should set an address for the PSX to program something else?

 

REgards

 

Steve

[BromsMods]

14 hours ago, steve45 said:

Am I correct in thinking you don't need to program the PSX at all if you simply connect a jumper from J6-2 to J6-1 to obtain 1.27 amperes or is there another reason why I should set an address for the PSX to program something else?

 

 

That's correct.  You can see (or download) the manual from https://tonystrains.com/pdf/dcc_specialties/PSX-Manual-Rev-N-Software-Rev-L-Booklet.pdf

[arff999]

On 03/01/2022 at 21:11, Dungrange said:

 

But you'd only use the PSX on the track power bus.  If you have a separate accessory bus which is connected on the Powercab side of the PSX, then you'd have 1.27A for the trains plus still have up to 0.73A for your accessories and a 2A Powercab can't supply any more power.

Not quite true.

The power cab has a 1.8A load output, so you would share the 1.8A across the track and accessory bus, you would only have 0.73A if you maxed out the load on the track.

Having said that, if you reached 1.27A then the trip would turn off the power anyway.