Your two-way machine works with three limits: the maximum per cash-in transaction (previously set in the admin), the maximum per cash-out transaction, and the amount up to which you'll accept cash-outs with zero-confirmations (with SMS redemption enabled above this).
If your machine is one-way, you can set the cash-in transaction limit using just the -a argument below.
For examples of usage, run in your DigitalOcean droplet's terminal:
To set a $1000 limit for cash-in, $500 limit for cash-out, and zero-confirmation cash-out transactions for $200 and under, run:
ssu-limits -a 1000 -d 500 -z 200
To set just a cash-in limit for $1000, run:
ssu-limits -a 1000