TV's suppressor location on layout question

When using a Powermaster and Powerhouse where would put additional  circuit breaker and tv's?

I used TVS on my 3 pw ZWs in this manner before going to PoHo 180s and placing them on T-strips.

Also installed them on T-strips for distribution to multiple railpower connections(soldered). Below: Plate-jumpered to enable 5 screws each for Hot and Common railpower connections soldered to rails in a single power district. TVS is connected like a direct short between the Hot (colored) and Common (white) from the transformer.

On pw ZWs: Connect one on each binding post(s) used for railpower, usually A/U&D/U.

Thanks Dewey

You might be adding one inside locos when they are apart as well if you have a pile and small roster.

Adriatic posted:

You might be adding one inside locos when they are apart as well if you have a pile and small roster.

Yes especially if your engines visit other layouts or run on modular layouts. 

I add them if I have to take something apart anyway, but I don't disassemble them just to add a TVS.

Does one size TVS fit all places of application when using 18 volts to a layout?

Pretty much, I use these. 

1500W 33.3V TVS at Digikey

For completeness:

For power supplies in excess of 18VAC use the 1.5KE36Ca diodes. This includes most Postwar Transformers (don't forget the whistle boosts)

If you only use supplies that are limited to 18 VAC then you could get by with 1.5KE33Ca diodes. This includes most power bricks and such.

Both types can be found on Mouser, DigiKey and similar electronics providers as well as the 'bay.

I have a new Z-4000K and don't use them on the transformer - only at every track connection.

I use a small terminal block at each drop with 14 ga. wire from the transformer on one side and 16 ga. to the track on the other with a TVS soldered onto the block.

Just as info: the TVS spec noted by GRUNNERJOHN and others is bi-directional, doesn't matter which direction you connect it. ( I assume that would eventually be a question-has been previousoly).

bmoran4 posted:

For completeness:

For power supplies in excess of 18VAC use the 1.5KE36Ca diodes. This includes most Postwar Transformers (don't forget the whistle boosts)

If you only use supplies that are limited to 18 VAC then you could get by with 1.5KE33Ca diodes. This includes most power bricks and such.

Both types can be found on Mouser, DigiKey and similar electronics providers as well as the 'bay.

Well, 24V RMS is 33.9 volts peak voltage, and the minimum breakdown of the 1.5KE39CA is 37.1 volts, so you're pretty safe.  In addition, if you look at the 1.5KE36Ca you call out, it's minimum breakdown is lower than the one I specify at 34.2V, so you're going the wrong way if you're worried about it having too low a voltage specification.  You may want to revisit your observations.

1.5KE39CA Specification (my choice)

1.5KE36CA Specification (your choice)

I think I'll stick with my recommendation!

@gunrunnerjohn - My mistake - I somehow thought you had followed the common recommend of the 1.5KE33Ca as the question pertained to an 18V supply. I now see that your recommendation for the 1.5KE39Ca is sufficiently overkill for most common scenarios.