Wiring Fastrack Turnouts - how much is too much?

Are you planning to install TVS diodes?

@VJandP posted:

1) How many turnouts is too many?  There are 13 turnouts that I want to power directly.

Limited only by space available & $$ - they draw almost no power when idle.

@VJandP posted:

...recommended way to ground the turnouts?

This one - Only run a hot wire and let it ground to the common rail.

@SteveH I don’t even know what those are LOL …. I was also reading about SC2 modules and wondering if I needed that.   When I get around to building a control panel .. relays, and toggles, and momentary switches … oh my!   So much to learn.

@ADCX Rob Thanks, Rob.  Appreciate the input.  That definitely simplifies the wiring.

@VJandP posted:

@SteveH I don’t even know what those are LOL …. I was also reading about SC2 modules and wondering if I needed that.   When I get around to building a control panel .. relays, and toggles, and momentary switches … oh my!   So much to learn.

I strongly suggest you read this thread about electrical protection of the electronics in your trains and accessories.  It covers TVS diodes fairly well:

Fuses and Circuit Breakers

Since you have the ZW-L, it has the Circuit Breaker protection fairly well covered, but the TVS diodes are made to work along with fast acting breakers to help protect electronics.

TVS diodes stand alone to protect electronic circuitry from voltage spikes / transients. The ZW-L will not shut down 8-9 amp derailment short circuits.

@ADCX Rob posted:

...The ZW-L will not shut down 8-9 amp derailment short circuits.

Rob, would you please elaborate on this.

Does the ZW-L limit the output current to the 8-9Amp range on individual outputs or are you saying derailments sometimes only draw this little current?

The ZW-L has a 10 amp breaker/current limiter and will continue to supply power until that limit is reached... so yes, a short that does not draw 10 amps( I just had a few of those derailments tonight) won't shut down that channel.

@SteveH, this 10A fold-back current limiter is discussed in the user manual on page 5: https://www.lionelsupport.com/...ZWLManual.pdf#page=5

Rob and Brian, thank you for this information.  This all makes sense to me now.  Do you think installing either 7.5A Airpax Instant or #91 breakers in the track circuit would be a good countermeasure (in conjunction with TVS diodes) to better protect electronics in the trains from the ZW-L during derailments?

Well, the 7.5A AirPax isn't guaranteed to trip until it hits 150% which is over 10A so it may not be as effective as we would expect:

Do you think installing either 7.5A Airpax Instant or #91 breakers in the track circuit would be a good countermeasure (in conjunction with TVS diodes) to better protect electronics in the trains from the ZW-L during derailments?

The danger is not from the ZW-L(it has nothing an old Type Z or ZW/KW/1033 etc. doesn't have)  The overload protection is for the transformer and wiring, and to some extent the wiring inside some rolling stock(which will burn up anyway as in the case of the Polar Express cars with their tiny wires).  4-5 amps will melt down the wires furnished with FasTrack sets & terminal tracks quite quickly.

TVS diode protection stands on its own for clamping the over-voltage spikes that pose the danger to sensitive electronics, so your choice of power district overload protection is really dependent on the loads you expect to encounter based on your equipment.  There just isn't a universal answer.

A ton of great info in this thread.   I have some reading to do!  Thank you, everyone.  

So much to learn in this hobby.

I'm using MTH Z-1000 100 Watt Transformers and their brick comes with a 6 amp circuit breaker, I have installed TVS Diodes coming out of the brick, out of the controller, along with a 5 amp automotive blade fuse and fuse holder coming out of the controller going to my barrier strip, and also at all the track feeder connections to the track. Eventually once I get all the track laid and wired, I plan to open up my locomotives and install TVS Diodes in all of them too. I was testing the one track I have all done except the yard, had a derailment, and it quickly popped the 5 amp fuse. Glad I have the fuse holder right behind the controller on top of the layout so it's easy to shut down my main power switch for the layout to do a quick change instead of underneath the layout!😁 I'm running conventional and was only at about halfway up on the speed dial. Play it safe and protect everything as well as you can.

FWIW, I can take a #30 wire-wrap wire and short the outputs of the Lionel Powerhouse 180 brick and it trips instantly.  I used a three foot length of that wire, it didn't melt the wire, just tripped breaker. I can also put a 9 amp load on the PH180 (four 8 ohm 75W resistors in parallel) and it'll run all day without tripping it's breaker.

You can't do much better than that.