摘要 |
A system and method for automatically adjusting an ORVR-compatible Stage II vapor recovery system to maintain the air-to-liquid (A/L) ratio within desired tolerances or limits to meet regulatory and/or other requirements. An air flow sensor (AFS) or vapor flow meter measures the amount of recovered vapor for a dispensing point to calculate the recovery efficiency of the system in the form of the A/L ratio. Volume or flow rate measurements can be used. ORVR fueling transactions are either minimized or excluded from the A/L ratio, so that the A/L ratio is not artificially lowered due to a blocked or altered recovery. The A/L ratio is then compared to a desired or nominal A/L ratio. Adjustments to the recovery system are made within prescribed safety tolerances if the A/L ratio differs from the desired ratio.
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