Cap Feeder Jam Detection specification should start with the real closure.
Many cap feed problems are not mechanical failures but undetected changes in cap flow. Jam detection can monitor chute fullness, bowl level, elevator demand and cap present signals so operators can clear issues before the capper stops repeatedly.
For a better buying decision, the useful comparison is not only hopper size or headline speed. It is how the feeder behaves with your closure, how the capper receives the cap and how easy the line is to run after changeover.
The safest specification route is to start with real closures, target output, line photos and the exact point where the cap must be presented. That avoids choosing a feeder on a generic speed figure that does not match the cap or capper.