What Size Replacement Circuit Breaker For A Lionel LW Transformer?

[MickeyDemian]

Hello All:

  I'm in the middle of upgrading a Lionel LW that I picked up.  Besides cleaning it, Ive udgraded the copper disc to a diode and am interested in placing an automatic resetting automotive circuit breaker in the unit.  My question is what size should I buy?  5-7-10-15 amp?  I know Ive repaired my ZW with a 15 amp breaker, but this unit is much smaller.  Any electrically minded wizards with an opinion?  I run mostly PW units.

 Thanks for your opinions:    Mickey

[lionelsoni]

Lionel claims 5.5 to 6 amperes.  You will probably be okay with 7 amperes, but 5 if you want to be very conservative.

You probably replaced the copper-oxide rectifier with a silicon rectifier, which is not really an upgrade but rather a work-around for an original diode that had failed.

[rrlineman]

the LW already somes with a self re-setting breaker. trying to retro fit a automotive style is a pain. try Henning's Scale models in Landsdale PA.. Harry has newer smaller versions in 5-7-12 and 15A .

but I wouldn't go any higher then a 5 amp personally. all Lionels breakers were made by WILCOLATER and have the wattage rating heat stamped on them. I belive your LW is 125 watts. just remember the breaker is there to protect the transformer, not your trains or wiring.

[lionelsoni]

I've never had any pain installing these:

This is picture of a Littelfuse UCB5.  You can connect to it with 1/4-inch female Faston connectors, or solder.  It has a "modified reset" feature that keeps it tripped until the load is removed, unlike the original Lionel breakers, which will recycle unconditionally.