For example, if you have something that draws 20 amps, and you use it for 20 minutes, then the amp-hours used would be 20 (amps) x .333 (hours), or 6.67 AH. The 20 Hour Rate is the accepted AH rating time period for batteries used in solar electric and backup power systems (and also for nearly all Deep Cycle batteries).
âYes, sir, a stop payment on a check is only valid for six months.â I asked if there was any way I could cancel the check permanently. âYes sir, you can renew your stop payment six months from now. For an additional $30.â At this point, I was getting agitated.
Report Abuse. Unless otherwise marked, checks go stale 6 months from the date on the check. US Treasury checks are marked as valid for one year however if your state refund check has not such markings it went stale back in September. You'll have to return it to the state and ask to have it reissued. Source(s): Used to work in the banking industry.