VLT Aqua Drive Lab # 3
(Process Closed Loop Operation)
Introduction
In this lab you will set up a VLT Aqua drive to simulate a closed loop pumping application.
When a VFD is set up for “closed loop operation”, it requires a set-point and some sort of
feedback from the system. The feedback will come from a 0-10 volt pressure transducer. The
drive will receive the start/stop signals by means of a SCADA system. The VFD will have one
relay output programmed to indicate when it is running at set-point pressure. A normally
closed over pressure switch is also wired back to the drive that will shut it down in the event
of a failure. For this lab, you will use the switch box found in your demo case to simulate the
SCADA signals. The instructor will explain how the switch boxes work before you begin the
lab
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4/29/15 2:47 PM