You should be OK

I use the NCE EB-1 circuit breakers and while my frogs are controlled with 3-way switches I do have two Tam Valley dual frog juicers that I use for my turntables. They are just wired to the regular bus wires, nothing special. I've never had any issues, that I know of, between the two. Not sure if the number of juicers would make any difference though.

Timing

The issue you can run into when chaining things like frog juicers and electronic breakers is timing.  Each thing takes a certain amount of time to detect the short and then do whatever it does.  You want the thing closest to the actual track to act the fastest, and each successive thing in the chain to have a little more delay.  Some things you can configure the delay on.

Apparently you got lucky in that the default delay values worked.  I don't think it will be load sensitive.

EB 1 and Frog Juicers

I have a Hex Frog Juicer after an EB1.  The EB1 is set to 2.5 amps and the response time is what ever the default is from NCE

Everything works as advertised. 

Hope this helps

Ernie

Competition between NCE breaker and Frog Juicer

A friend of mine had this problem.  Made the adjustments listed in "PSX CV Settings" and it worked fine.

http://www.sbs4dcc.com/tutorialstipstricks/psxandfrogjuicersshortcircuitconflict.html

The relevant paragraphs are here.

There are two undocumented (as of this writing) CV's to adjust the trip rate or sensitivity of the PSX Circuit Breaker.
As they are undocumented, they remain unnamed.

I believe CV55 enables CV65 and CV65 is trip time as measured in milliseconds.
Set CV55=1 and CV65=128.

Adjust CV65 in increments of 8 to fine tune the sensitivity to perform as desired in your installation.
 

I think I've got it

Thanks all.

Lemme get this straight, as long as:

frog juicer trip time < power district circuit breaker trip time < booster trip time 

... I should be good. The juicers have jumpers to set trip current, not trip time, but lower current should correlate with shorter trip time.  The link Dave provides and the articles on the NCE site suggest that the circuit breaker trip time is configurable via CVs. 

I guess I'll still need to test for how my setup handles actual shorts, which I'll first conduct with quarters but inevitably I imagine will involve my most expensive and hard-to-replace decoders. As the NCE docs make clear, the circuit breakers aren't intended to protect decoders, they're to protect boosters. Makes me appreciate the poor sods with really big layouts, clubs, and modular organizations. 

Fun hobby!

Jeff Allen

Suggestion to change your formula

Frog juicer trip current < PSX trip current < Booster trip current.  

For example,Tam Valley Juicer are set to trip at 2 amps (per the manual "...When the microprocessor senses a current greater than 2 A at a given frog..."), but your PSX is set to less than 2 amp, the frog juicer will never activate.

All 50+ turnouts on my layout use the Hex Juicers, all are fed by a dedicate Frog Juice bus that sources it power from a bus bar just off the booster (bypassing the PSX's).  

time vs. current

Dag nab it Bob, I was just starting to have hope for clarity. I found the CV listing for my EB-1 TIME values (I'm not using a PSX as in your formula) and I have the jumper settings for frog juicer CURRENT limits, but apparently I don't get to manage both using the same units! 

And another thing, it's all well and good that you wired your hex juicers properly using a dedicated bus but you're really making me feel bad for even suggesting that I might try to get away with anything less.

If my empirical tests don't settle the issue I will ultimately do the same. It just means ordering more wire and running another pair, but that makes sense. . 

Jeff Allen

All hooked up and running as hoped

I got all twelve frogs on the Day Branch juiced today. A quarter on the track instantly trips the EB-1 with a quick recovery. Not a whiff of smoke anywhere. 

Lucky me! Thanks everyone for helpful input. Now I'm realizing that this issue may explain another problem I was having with slight locomotive hesitation at an electrical block boundary - what appeared to be an "out of phase" condition but which was unchanged when I reversed track polarity and booster polarity. Now it's dawning on me that the gap is at the insulated rail joiners of a switch with a frog juicer. 

Tomorrow I intend to discover of that problem goes away if I don't juice the frog. 

Onward.

Jeff Allen

Frog juicers and EB1 /SB5

Hi bob morning

juat reading your comment here. I have about 50 turnouts with frog juicers. Just wired up the NCE SB5 with an EB1 and the light on each juicer barely comes on. Did you have this problem? And should I do as you and have seperate bus wire for the juicers and/or wire the juicers straight from the booster? 
 

any help would be appreciated!
regards

MB