I had purchased one several years ago that developed an internal short within the warranty period. Because I worked relatively close to MRC's Edison, NJ location I drove over during my lunch hour. The tech there spent some time trying to isolate the cause of the short and wound up giving me a replacement unit. I had wanted a brand new one, but that was not to be. The replacement has performed flawlessly ever since.
Bruce
Think you just got a bad one. I had the 9500 and I loved it till I went DCC.
Cuda Ken
I hate Rust
I have had two other packs on this layout without any issue. I have a control master 20 that works perfect and I had a Tech2 2500. The intention was to replace the 2500 due to its age. I never had a problem until recent with the two other packs. I put the 2500 back into service and have had no problems since. I think I got a bad unit with the Tech 3, they are going to replace it and I have heard others say they had problems with the Tech4 and its pre-mature overload issue.
It sounds like more of a problem with either the layout/wiring or the locos. If you've had similar issues with 2 different power packs, it seems the power packs have been doing what they're supposed to do when there's an over load. You should get a volt/ohm meter and check for shorts in the track and wiring. With the meter set for continuity, and nothing on the track and disconnected from any power packs, put a probe on each rail, the meter will beep if there is a short. Do this in several places around the layout.
The other option would be the locomotives. Check to see if the wheels of drive are binding, if you're unsure how to do this, you could take them to you local hobby shop and ask them to check them out for you.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
Does the unit have a breaker in it? you may have had a temporary short and tripped the breaker if it has one. It might also be called a reset switch on the unit.
Springfield PA
I had a problem with my Tech 3 9500 yesterday. All was fine then all of a sudden the unit shut off and that was it, noi power no lights, no funtions. There is power to the outlet and I tried it in other outlets as well. This unit is less than a week old and I sent it back for a replacement but my question is has anyone else had this problem? I am a little gun shy with getting another but I guess I will try it again. I had a Tech4 but that thing was junk, it would overload with 2 Athearns at less than 5 minutes runtime. Now it just runs signals