Hi Jay,

> +12 to +60 Vdc input

At the 1. view I found only DC-DC converters with 1:4 input range (9-36V or 18-72V).
Size for 5V, 3A output: 50 * 50 * 10 mm³


> swings as long
> as 3 seconds up to 120 Vdc or down to -60 Vdc

It depends from the pulse duration. If the 120 Vdc and -60 Vdc pulses are short, a coil in series may work.


Peter