The company was concerned about finding a drive to replace an obsolete unit. The new drive needed to fit into an existing cabinet to avoid the cost and time of building a replacement.
ABB value provider APDS recommended installing an ABB general purpose drive – the ACS480 – which is said to have a compact physical size and low power rating range (0.75 to 22 kW), making it an ideal fit for fans, pumps, mixers, conveyors and compressors most commonly found in the food and beverage industry.
The ABB drive is also said to be facilitating more consistent end-product quality by applying closed loop control to the blending process. As the soft water pump feeds four blending cells, it is critical that the water pressure remains constant.
The closed loop control is provided by a PID (Proportional-Integral-Derivative) controller. This is included in the VSD software, which is inserted within the control loop so that the loop can be tuned to ensure stable and accurate control. PID control is a mathematical algorithm that is used to control a range of parameters, such as flow and pressure, according to ABB.
A pressure transducer in the water tank also feeds a signal to the VSD. As the pressure of the water varies, the pump’s speed is adjusted accordingly. This provides a constant flow of water into the system, ensuring the fruit juices are mixed to the right consistency every time. The VSD’s control keypad, also known as an assistance control panel, also offers Framptons more intelligence on the process.
Tom Dowson, site services manager at the Shepton Mallet facility, comments: “Since the drive was installed, we haven’t had to do anything with it – it has simply done exactly what it is supposed to. An added benefit, however, is how much process information we are now able get from the drive, using the keypad. As a result, fault finding is now faster and more efficient.
“Previously, if the pump wasn’t running as expected, or if the water flow rate wasn’t as high as required, we would have to put an amp meter inline and measure the current from it. With the ABB drive, that information is displayed on the screen.”
Dowson adds: “Around 80-90% of the site’s electrical consumption is used to power pumps or move product, so it’s critical these applications are as efficient as possible. We fit drives on all equipment rated over 75 kW and are also in the process of upgrading our existing IE2 motors to ABB IE4 high efficiency motors.”