Why was the trace to power terminal of Lionel SC-2 cut?

I wasn't aware of this, but found a few threads:

https://ogrforum.com/...70#94769632073646770

https://ogrforum.com/...64#38737270680662564

https://ogrforum.com/...23#24378330593506723

https://ogrforum.com/...412#6216614256285412

https://ogrforum.com/...055#5371679460868055

And here is the search I used to find them: (I cant link it this way, but click "show search query" to modify it if desired)

https://ogrforum.com/...ation.sort=ITEM_DATE

-Dave

I see my problem. I used "SC-2 cut trace" should have used "SC-2 trace".

More importantly, in my post above, there is a mistake. The cut trace is NOT to break power from the rear plug, it is to disconnect 'Common' from the center of the first terminal block. This makes much more sense as to why one would want to cut the trace.

I edited the post with strike through for the wrong info.

Yep, the first channel had the common wired to the aux power, if you cut that trace, all the relays are totally isolated and you are free to use them for any purpose.  This is a mod I did to all of them that I was using.  It's a throwback to when they were used for controlling 022 switches I suspect.

Note that the SC-2 could be powered two ways.  There was a provided wall wart, that plugged into the SC-2, or you could use track power/aux power.  (The cut traces).   You can cut the traces, as long as you understand, the operational power to the SC-2, is via the Wall wart.   SC-2 also operated the same as an engine, gaining TMCC signal from the nearest outside rail.  There was discussion about the position of the SC-2, near rails, so that TMCC signal was available.   

You can use wall wart or the A and U terminals with the trace cut. I use the A and U terminals with the trace cut and I connect the outside rail wire to the U terminal which benefited the operation immensely.

I also string a ground wire over the bank of SC-2s since they are under the layout.

When I ran them with the wall warts and none of the above changes, operation was very poor. Now my multiple switch routes switch with only a half second delay between switches.