The output of Marklin controllers is AC, intended for use with their locomotives that operate on "3-rail" track. Although in their case, the center rail is actually a series of studs sticking up from a bus under the roadbed. AC power can damage the DC motors in locomotives designed to operate on 2-rail track. You could use the Marklin controller to supply variable AC power to lights or accessories designed to operate on AC.
Len
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