I have an old Marnold power pack from the 1950’s that I would like to use temporarily on an HO layout before investing in DCC. It’s probably been used less than 200 hours. I checked the output with a VOM and get 16VAC and 16V fixed and variable DC. Do the selenium rectifiers deteriorate with age? And if they do, is there a chance they could damage locomotive motors?
Yep, selenium rectifers do deterioate over time. I would be a bit leary of this power pack, especailly if using it with engines with can motors or high quality skew wound motors. Even when new these older power packs had a certain amount of AC leakage as the DC output was not filtered. With the older open frame motors this really didn’t present a problem as they were not as susectable to heat and could throw it off. Can motors are very sensitive to any AC current and cannot dissipate the heat caused by AC leakage fast enough and will be damaged by the leakage. Also that old Marnold pack probably has a start voltage in excess of 3 Volts DC which will give you very little in the way of speed control on the locomotives of today. Hope this helps…Vic
You’re right, it does have a rather high starting voltage. Thanks for the information. I’ll put it back in storage with my other RR antiques/junk.