If you are using Peco turnout motors, you should be using Peco momentary contact switches which means you should add this capacitor discharge unit. I have had no trouble at all with my turnouts since running power through the PL-35. Although it takes both AC & DC input, the 12 volt DC doesn't really generate enough power to operate the turnout motors properly. I contacted Peco about this unit and was advised to use 16 volt AC which I do. Peco also advised me that I should not use power greater than 16 volts AC (the standard in England). Make sure you meter the AC output of your power supply. They oftentimes discharge more power than they state. The unit measures 3 1/4 x 1 1/2 x 7/8.

this unit works great with peco turnouts work just great no hesitations with switching