by Rob-NYC »
Thu Apr 16, 2015 3:15 am
As Ron pointed out, it is the button switches.
The circuit daisy-chains through the 5th switch to the 4th and so-on. If a break in continuity occurs at the out position of a switch due to pitting or broken slide contact all the categories to the left of that switch become unavailable.
Aside from a-hole kids punching the buttons for fun, the AC drum motor draws just over 3 amps through the switch contacts and they arc as soon as they lose a bit of tension due to use. This eats away available conductive metal and eventually you have an open circuit. The sliders can break off as well.
I solve the current problem by using a 24 VAC relay to operate the motor and this reduces the switch current to around 30ma.
When the contacts break off or the phenolic simply falls apart I have to make a new one from switch parts I bought back in the 80's here in NYC.
I can see why so many of these machines were "Wico'ed".
Rob/NYC
"If we believe absurdities, we shall commit atrocities" -- Voltaire