DCC conundrum

[FlattenedQuarter]

Here's the deal. Just fired up my new( and 1st layout) 3 mainlines and several branches, 360' +/- of track with NCE PH Pro5 wireless. I'm running mainly LifeLike P2Ks that I've converted to DCC. When I run multiple, up to 4 so far(not consisted) GP7s, GP9s and my Atlas HH660 everything works great. Different directions and speeds all good. I also have LLP2K  PAs. They work fine individually when they are the only thing on the track. When I add the other PA or any other locomotives things get wonky and my circuit breaker starts tripping continuously. I've reset to default the PA decoders and reassigned their #s both long addresses. Seems like if there was an internal problem of some sort they wouldn't operate fine by themselves. Are they drawing too much power? I would have thought 5 amps was plenty of juice. Any insights would be appreciated.

thanks

[tstage]

FQ,

A few questions for you:

1. Did you try running both PAs on address "3" before programming the long address?
2. When you "add...any other locomotive" to either Proto 2000 PA, do they both exhibit the exact same behavior - i.e. trip the circuit breaker?
3. Do your PAs trip the breaker in one particular area of your layout...or anywhere on your layout?
4. Did you try operating your PAs together with the shell off?

The questions may seem rather arbitrary.  However, there is madness to the method.

Tom

[BigDaddy]

Did the PA's run on DC before you converted them?

[FlattenedQuarter]

1. They both ran fine on the program track on “3”

2. The addition of any other locomotive to either PA creates the same result.

3. Doesn’t seem to matter where on the track.

4. Run fine on programming track individually with shell off, haven’t tried that on the layout.

5. Both ran fine in DC.

[FlattenedQuarter]

12 awg bus with 18 awg feeders , no feeders longer than 18” bus feed from center, 30’ max from power supply.

[rrinker]

 There was a run of thopse PAs back in the day that had motors that drew a LOT of current - on the order of 3 amps. You might have some of those, though how they aren't frying the decoder is another mystery. 

                                  --Randy

[RR_Mel]

Do you have a meter that will read the DCC voltage on the track?  If so measure the voltage on the rails with out any locomotives on the track then with the meter reading the voltage put a PA on the track and see if there is significant voltage drop.  Compare the second PA to the first.  Then check one of your other locomotive and compare it to the PAs.  If there is a big difference check your wiring on the PAs for an error.



 

Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

[MisterBeasley]

Are you connecting anything else to track power besides locomotives?  Any structure lighting?  Any stationary decoders?  Any illuminated passenger cars?  All of these draw power.

How about dividing your layout into power districts with circuit breakers?  If so, each district is now limited by the allowed breaker current that the breaker is set to, not the total system current.

[richg1998]

I have always run DC amps check on all my locos before converting. You never know otherwise.

I use to have a DCC amp meter which was a good check.

Rich

 

[FlattenedQuarter]

Just had a thought, I’m using a single NCE EB1 circuit breaker. Factory setting is 1.5 amps so maybe I need to adjust that?

all other electric users are supplied by separate bus and power source.

[restorator]

The lifelike/proto PAs have a metal frame and unless you did a lot of isolation, with kadee metal couplers they make a short through the coupler when run back to back. Ask me how I know this....

[BigDaddy]

restorator

The lifelike/proto PAs have a metal frame and unless you did a lot of isolation, with kadee metal couplers they make a short through the coupler when run back to back. Ask me how I know this....

I was wondering if this was like an Athearn BB situation.

[maxman]

The PH Pro has an internal circuit breaker the trips at some value less than 5 amps.  If you have another circuit breaker in series with the PH pro circuit breaker, the circuit will be interrupted by whichever breaker has the lowest set point.

[FlattenedQuarter]

Update, the EB-1 is factory set at 1.5 amps, I kicked it up to the next setting of 2.2 amps and now both PAs run fine opposite directions on two mainlines. I haven’t yet added any more locomotives.

[rrinker]

 It's important to give all information - this is a prime example. There should not be a problem with a 5 amp system runnign the listed locos at the same time, let alone it dropping out with just one specific model plus another. 

 But one piece of missing information - between the 5 amp power and the rails is a circuit breaker set to 1.1 amps. So the load being placed ont he rails was exceeding 1.1 amps, not 5 amps. 

 I would recommend getting a second EB-1, set that to 2.2 amps as well, then figure out where the approximate halfway point is on the layout based on where and how many trains runs at a time. Gap both rails in two places to make two separate sections, divide the power bus the same way, and add the second EB-1 to power the second section. 

                                 --Randy

 

[FlattenedQuarter]

Usually you don’t know what all the information needed is until you discover the solution. The questions asked by respondents lead to the light bulb coming on as is often the case. Thanks everyone

[BigDaddy]

Don't sweat it Flattened Quarter. 

These electronic mysteries are frequently like Columbo mysteries.  The shown track plan is doesn't include the reversing loop or the DCC engine was bought on ebay and was never tested on DC before decoder installation or there is both DC and DCC hooked up to the layout.