What is the proof switch, under speed and under adjust ingredient menu on the HI 3010?

What is the HI 3010 filler/dispense proof switch, under the adjust ingredient/speed menu? Please explain why I would use a proof switch and timer.

Proof switches are used and available for the fast, slow feed, and discharge gates. Proof switches are physically attached to a valve or gate so when the valve changes state the switch will also change state.

If you have an application with fast and slow feed you could use a proof switch to indicate the valve is operating correctly. Also this same application can have a proof switch on the discharge gate to insure there is correct operation during fill and discharge.

There are timers associated with each proof switch. Every switch operation opens and closes at different rates. You should monitor the proof switch by setting a timers to a duration slightly longer than you would consider normal. You may need to adjust these timer settings to stop intermittent nuisance alarms.