The ACS310comes standard with two independent, built-in PID controllers for regulatingpressure, flow or other quantities on the basis of the actual need. The secondPID controller can eliminate the need for an external PID controller, and helpsto improve the quality of the process, save energy and up-front costs.

Pump and fan control (PFC)switches auxiliary pumps on and off, as required by capacity changes.Auto-change function alternates between pumps to keep the duty times of thepumps equal. With PFC feature, one drive is able to control several pumps orfans in parallel. An Auto-change function (when enabled and with theappropriate switchgear) equalizes duty time between the pump motors.Auto-change periodically increments the position of each motor in the rotation- that is, the speed-regulated motor becomes the last auxiliary motor, and thefirst auxiliary motor becomes the speed-regulated motor, etc. Interlocksfunction enables the drive to detect if any of the pumps are unavailable (ex.switched off for maintenance), in which case, the next available pump is started,instead.

Soft pump and fan control(SPFC) is used for pump and fan alternation applications where lower pressurepeaks are desirable when a new auxiliary motor is connected online. SPFC is aneasy way to implement soft starting of direct on line auxiliary motors. Themain difference between traditional PFC and SPFC is the way SPFC connectsauxiliary motors online -- with a flying start, while the motor is stillcoasting. Thus, in some cases, SPFC makes it possible to soften the start-upcurrent while connecting auxiliary motors online. This is why lower-pressurepeaks on the pipelines and pumps also may be achieved. SPFC control requiresthe Auto-change function, and the appropriate switchgear.

The ACS310comes standard with advanced pump protection functions such as Pipe Fill, apre-programmed control method to start a pump system and fill the pipelines.Pipelines are filled smoothly with water, before closed-loop control isactivated. Pump Cleaning executes pre-programmed cleaning sequence for pump atdrive start or when required with some other source, like digital inputs orcurrent/torque limits. Pump Cavitation function allows supervision of pumpinlet and outlet pressure through external sensors. The Pump Protectionfunction can be used to generate an alarm on the display, provide protectionduring the event, or trip the drive on a fault.

Variable frequency drives(VFDs) save energy, compared to other flow-control methods such as throttling.There are additional efficiencies achieved through monitoring, analyzing andoptimizing VFD system operation. In combination these features contribute toreal energy efficiency and value.

ABB drives have built-in energy efficiency countersthat calculate the energy savings of the application in kWh and MWh -- the costof the energy saved in a local currency; and the carbon dioxide (CO2) emissionsequivalent of the energy saved. The ACS310 includes other advanced energyefficiency features, like the built-in statistical tool Load Analyzer, whichsaves process data, such as current and torque values that can be used toanalyze energy efficiency of the pumping process. The energy optimizeroptimizes the flux so that the total energy consumption and motor-noise levelare reduced when the drive operates below the nominal load. The totalefficiency of the drive system can be improved by up to 10 percent, dependingon load torque and speed.

Usefulapplications include: motor speed control in various conveyor applications;pressure and temperature control like that used in ventilation systems; flowcontrol in pumping systems; and different kinds of level-control applications.

ACS310 Pump & Fan AC Drive