Fast breaker recommendation wanted

I use the 5A, instant-trip, Sensata/Airpax SNAPAK hydraulic-magnetic circuit breakers, part # PP11-0-5.00A-OB-V. I also have an 8A version, part # PR11-0-8.00A-XX-V. The key numbers are the "0" after the first hyphen, which indicates that it is instant and the other is the current rating after the second hyphen.  (They're called "hydraulic magnetic," but it's the delay that is controlled by the hydraulic component. Since those with a "0" are instant-trip, they don't use a hydraulic component and are just magnetic. Nonetheless, they're listed as "hydraulic magnetic.") DATASHEET.

Here are Digikey's stock of the Push-Pull and their Push-to-Reset.
Here are Online Component's stock of Push-Pull and Push-to-Reset.

As the current draw gets near to the circuit breaker rating, you can hear a buzzing, which only happens with certain locomotives and consists. My solution was to install both a 5A and 8A breaker and a SPDT switch, so on the occasions that my train consist is drawing enough current to cause the 5A breaker to buzz in normal operation, I switch power to run through the 8A breaker.

Matt,

Agreed.

Thank you for summarizing this so nicely for the OP.  Several of us have commented in the many threads on this topic that have sprung up over the last 5 years or so.  Rather than needing to dig through all of those Ken gets a very precise, and quite accurate, summary in your response.

Perfectly to the point.  Keep up the good work.

Mike

Henning’s Trains has the fast acting in line circuit breakers that you need.  I’ve used them as added insurance, even though I have a modern Z4000 transformer.  Can’t be too careful with the modern locomotives with the fancy electronics as they are very expensive to fix.  

Ken

Take a look at the PSXX-1 at Tony's Trains.  It is very fast, and you can use it to trip at different amperages.  A little pricey but it works great.  If you want good insurance for protection this, is it.

Marty

I'm with Matt, those AirPax breakers are great.  They're also reasonably priced if you shop around.

Thanks for the recs. I ordered the three 5A and three 8A Digi-Key had, plus restocked on SPDTs.

Jim Barrett had a demonstration on how to build your own in Backshop video 8.

Gary - good video. Can you list a specific part number and website?

@Mark V. Spadaro posted:

Gary - good video. Can you list a specific part number and website?

Mark,

I am pretty sure the PSX-1 AC is unavailable (like so many great things).  Check anyway though.

John

@Matt_GNo27 posted:

I use the 5A, instant-trip, Sensata/Airpax SNAPAK hydraulic-magnetic circuit breakers, part # PP11-0-5.00A-OB-V. I also have an 8A version, part # PR11-0-8.00A-XX-V. The key numbers are the "0" after the first hyphen, which indicates that it is instant and the other is the current rating after the second hyphen.  (They're called "hydraulic magnetic," but it's the delay that is controlled by the hydraulic component. Since those with a "0" are instant-trip, they don't use a hydraulic component and are just magnetic. Nonetheless, they're listed as "hydraulic magnetic.") DATASHEET.

Here are Digikey's stock of the Push-Pull and their Push-to-Reset.
Here are Online Component's stock of Push-Pull and Push-to-Reset.

As the current draw gets near to the circuit breaker rating, you can hear a buzzing, which only happens with certain locomotives and consists. My solution was to install both a 5A and 8A breaker and a SPDT switch, so on the occasions that my train consist is drawing enough current to cause the 5A breaker to buzz in normal operation, I switch power to run through the 8A breaker.

The Sensata breakers are great. One thing I’ve often wondered though is if the other model they offer with a -69 instead of a -0 would buzz less. That version is listed as an instant trip curve for 50/60 Hz current.

@Craftech posted:

Mark,

I am pretty sure the PSX-1 AC is unavailable (like so many great things).  Check anyway though.

John

Tony's hopes to have them back in stock by the end of the year or early next.

@martind posted:

Take a look at the PSXX-1 at Tony's Trains.  It is very fast, and you can use it to trip at different amperages.  A little pricey but it works great.  If you want good insurance for protection this, is it.

@Craftech posted:

I am pretty sure the PSX-1 AC is unavailable (like so many great things).  Check anyway though.

@superwarp1 posted:

Tony's hopes to have them back in stock by the end of the year or early next.

Remember though that the PSX-1's do not work below 10 VAC.  That means that they can't be used on the downstream (output) side of a traditional transformer or ZW-L for conventional control, if that's the control method you prefer.

In spite of this you may be able to place them upstream of a PowerMaster or ZW-C throttle head unit (between your PH-180 or -135 and the PM or ZW-C) to control conventionally and get the benefits of their excellent performance at the same time.

Mike

@Mellow Hudson Mike posted:

Remember though that the PSX-1's do not work below 10 VAC.  That means that they can't be used on the downstream (output) side of a traditional transformer or ZW-L for conventional control, if that's the control method you prefer.

In spite of this you may be able to place them upstream of a PowerMaster or ZW-C throttle head unit (between your PH-180 or -135 and the PM or ZW-C) to control conventionally and get the benefits of their excellent performance at the same time.

Mike

Exactly

I installed the 8A version, PR11-0-8.00A-XX-V on several of my cabs. I've been running diesels fine. Today, I ran a Williams USRA 2-8-2. The breaker tripped on a couple of Gargraves switches soon after startup, but then didn't later on different Gargraves switches. A lighted Lionel B&O wagon top caboose tripped the breaker going through a Ross 11 degree crossing with DZ-1008 power routing in one direction, but not the other. Have not done any investigation yet. I thought I'd check here with those with more experience.

@Ken Wing posted:

The breaker tripped...

I would investigate any blind drivers on the locomotive. Ones that are wider tend to short on Ross and GarGraves switches.

Fast acting breakers will definitely reveal problems like this.

And the solution is to turn the blind drivers narrower on a lathe????  Please advise.

@Ken Wing posted:

And the solution is to turn the blind drivers narrower on a lathe????  Please advise.

That was the only fix for the wide blind drivers on my Lionel scale PRR T1 and Ross switches.  I tried nail polish, tape, filed, but they were so wide that was the only solution.

@Ken Wing posted:

And the solution is to turn the blind drivers narrower on a lathe????  Please advise.

@CAPPilot posted:

That was the only fix for the wide blind drivers on my Lionel scale PRR T1 and Ross switches.  I tried nail polish, tape, filed, but they were so wide that was the only solution.

Same here. I chose to bevel them on my T1... like most of the modern locomotives are done.

I had made a post about my beveling of the drivers and how I did it. But I can't find the post now.

@Ken Wing posted:

And the solution is to turn the blind drivers narrower on a lathe????  Please advise.

Actually, it's possible to fix the Lionel scale T1 Duplex without a lathe.  I used a Dremel with a 220 grit sanding wheel.  Actually, I ended up using several sanding wheels to do the whole job.  I covered everything I could with rags and rigged a vacuum right at the wheel I was working on to minimize the dust from getting inside.  You need about a 15 degree bevel that spans roughly half the blind drivers from the inside to fix the problem.

Ouch.

@superwarp1 posted:

Tony's hopes to have them back in stock by the end of the year or early next.

They’re currently back in stock at Tony’s Trains.

@rplst8 posted:

The Sensata breakers are great. One thing I’ve often wondered though is if the other model they offer with a -69 instead of a -0 would buzz less. That version is listed as an instant trip curve for 50/60 Hz current.

Ryan, good point.  According to an Octopart search, the Sensata / Airpax Instant PP11-69- seem to be available only by special order with a long lead time.

Has anyone tried these Sensata Airpax Instant with the first two decision options: PP11-69- ?   If so, have you compared them to the PP11-0- to see if there are any differences in buzzing sound near their upper current rating?

Please consider sharing your findings if you have tried the PP11-69- series.

Thank you,

SteveH