ACIS-3 (Closed-Loop Control with NOx Sensors)
The ACIS-3 Closed-Loop Control system utilizes NOx sensors for pre-SCR and post-SCR NOx values, which it then uses to adjust urea injection to constantly achieve a specific NOx target. It continuously monitors urea injection rate and compares to the desired rate and adjusts accordingly. NOx targets of 25 ppm or greater, concurrent with low ammonia slip, can be maintained with the ACIS-3 control system.
Operator interface is via a powerful yet simple HMI with graphical representation of the entire emission system. An operator can see at a glance critical operating information such as temperatures, NOx measurements, injection rate, exhaust pressure, etc.
ACIS-II (Closed-Loop Control with Electrochemical Analyzer)
The ACIS-II Closed-Loop Control system has an on-board measurement of post-SCR NOx values, which it then uses to adjust urea injection to constantly achieve a specific NOx target. NOx targets of 5 ppm or lower, with concurrent low ammonia slip, can be maintained with the ACIS-II control system.
Like the ACIS-3, the ACIS-II has a powerful HMI which makes monitoring and setting up the system simple.