為了解決上述問題，ADD指令的使能輸入應(yīng)該來自一個(gè)跳變(單觸發(fā))線圈，如下面所述。在改良的電路里，%10001輸入開關(guān)控制–個(gè)跳變(單觸發(fā))線圈，%M0001的觸點(diǎn)接通ADD功能塊的使能輸入，每次掃描%M000使觸點(diǎn)%10001閉合-次。為了使%M0001觸點(diǎn)再次閉合，觸點(diǎn)%10001只能再次分來閉合。

ALLEN BRADLEY 1326AH-B540F-21 USPP 1326AHB540F21

ALLEN BRADLEY 1770-HT1 NSPP 1770HT1

ALLEN BRADLEY 1779-KP2 USPP 1779KP2

ALLEN BRADLEY 1397-802275-2R NSPP 13978022752R

FANUC A20B-1000-0180/?09A USPP A20B1000018009A

SIEMENS 6FX1-192-3AB00 USPP 6FX11923AB00

SIEMENS 6SE9-215-2BB40 NSFP 6SE92152BB40

WESTINGHOUSE 289B142A11 USPP 289B142A11

TEXAS INSTRUMENTS 500-2114A NSFP 5002114A

HEIDENHAIN CORP LC-191-F NSPP LC191F

CONTROL TECHNIQUES 75DMA300HAAAA NSPP 75DMA300HAAAA

MEASUREX 05435800 NSPP 05435800

MODICON AS-B984-100 USPP ASB984100

ALLEN BRADLEY 150-A35NB-ND-8L?4A USPP 150A35NBND8L4A

ALLEN BRADLEY 810-A20BZ USPP 810A20BZ

ROBO CYLINDER RCS-SMR-A-100-M?-700-T1-M NSPP RCSSMRA100M