Robert, I think I got (most of) it.
The terminals are used both for input and output.
20A @ 24VDC as output terminals.
Disconnected from that discharge use and switched to the charging configuration.
As input (re-)charging terminals, the output circuitry use would be inactivated.
And, essentially, those terminals directly connected to the EESU capacitor terminals.
Don't think that voltage rise is going to be linear.
Very very quick rise, initially from 0V (or whatever the residual voltage is).
Very limited rise / approaching flat, nearing 3500V (or 5000V).
In any case, not recharged directly (in 90 seconds) from an ordinary household 15 or 20 Amp circuit!
90 seconds is going to require that the "specialized charger" have an embedded (second) EESU which can be slow charged via a wall socket, but provides the kick ass power to supply the entire charge in just 90 seconds.
I wonder if physical EESU module swap wouldn't be better.
But that wouldn't have the same sex appeal of a 90 second recharge, would it.
Even though the "specialized charger" takes, oh, 1/3 hour (20 minutes) using ~15A @ 120VAC, to be ready to provide the next 90 second full phaser blast.
Go DW Go - *economical* mass production