Auto Tuning of the PI Controllers
With auto tuning of the PI controllers, the drive monitor how the system reacts on corrections made by the drive – and learns from it, so that precise and stable operation is achieved quickly.
Gain factors for PI are continuously changed to compensate for changing characteristics of the loads. This applies to each PI controller in the 4-menu sets individually. Exact P and I settings at start-up will not be necessary, which lowers the commissioning costs.
Pipe Fill Mode
The controlled (closed loop) filling of pipes prevents water hammering, bursting water pipes or blown off sprinkler heads. This feature is useful in irrigation systems, water supply systems, etc.
End of Pump Curve Detects Breaks and Leakage
The “End of curve” function triggers an alarm, shuts off the pump, or performs another programmed action whenever a pump is found running at full speed without creating the desired pressure – a situation that can arise when a pipe breaks or leakage occurs.
Sleep Mode
Sleep Mode keeps pump wear and power consumption to an absolute minimum. In low flow situations, the pump will boost the system pressure and then stop.
Monitoring the pressure, the VLT® AQUA Drive will restart when the pressure falls below the required level.
Dry Pump Protection Lowers Maintenance Costs
The VLT® AQUA Drive constantly evaluates the condition of the pump, based on internal frequency/power measurements. In case of low power consumption at high speed – indicating a no flow or low flow situation – the VLT® AQUA Drive can be programmed to stop.
Two-step Ramps
Fast acceleration of the pumps to the minimum frequency prevents submersible borehole pumps from excessive wear and damage. They are quickly brought up to minimum speed from where the normal ramp takes over.
The two-step final ramp prevents check valves to close unintended and create water hammering.
Sensorless Pressure or Flow Control
Sensorless pressure or flow control is a patented VLT® feature that allows pump manufacturers to control the constant head (pressure) or flow levels without the use of sensors.
The cost and time of installing, cabling and maintaining pressure and flow transducers are eliminated. Reliability also is increased, as no additional components or connections can cause malfunction.
Payback Time Indication
One of the major reasons for applying a VLT® drive is the very short payback time due to energy savings. The VLT® AQUA drive comes with a unique feature which continuously shows the remaining payback time for the investment.
The user enters the specific energy price, the investment and the load profile for the application – the drive makes the calculation and provides the result. All this is easily done with the Danfoss Drives energy calculation PC software, VLT® Energy Box.
Preventive Maintenance Function
20 preventive maintenance events can be scheduled based on the Real Time Clock, running hours or operating hours. Items can be user-defined words/messages, for example ”Service pump 1.”
Complete Motor Control for the Water Business with VLT® AQUA Drive
A complete package of complementary products is available with the VLT® AQUA Drive:
• A broad range of soft starters
• Decentral drive solutions
• 5% and 10% passive AHF harmonic filters
• dU/dt and sine wave filters
Software
• MCT 10 PC software tool for drive supervision and programming
• MCT 31 PC software tool for harmonic calculations
• VLT® Energy Box for calculation of energy savings
Service
Danfoss service organisation is present in more than 100 countries – ready to respond whenever and wherever you need, around the clock, 7 days a week.
