Frequency drives are an integral part of any modern and efficient production. And this is understandable, because using of VFDs provides obvious benefits - reducing energy consumption and automatic process control, high accuracy of maintaining the value of the technological parameter and minimizing the overspending of raw materials, reducing the cost of repairing motors and moving control elements (valves, gates, dampers).
But on the other hand, frequency drives are sensitive to poor-quality power supply and voltage drops. Often the technological process is interrupted just because the converter stops, and restarting it can take from 5 seconds to several minutes. And all this leads to losses, billets damage and lower profits.
The AT27 frequency drives have a solution - this is the advance of the AT27. In the event of a power failure, the motor will stop, but the AT27 VFD will continue to monitor the motor speed. What is the benefit of this event? During restoring the voltage in the network or triggering the automatic throw-over circuit-breaker, it doesn`t take time to restore the system, the AT27 is already in operation and carries out the work according to the task. No emergency stops and stress for staff on duty!
We`ll tell a little about the physical features of the advance of AT27. If the input voltage fails in this mode, the AT27 reduces the frequency of the output voltage, thereby putting the motor into generator mode. The systematic motor stops, and the frequency drive maintains the voltage across the DC link capacitors in the operating range.
You may say: “Nothing special. In this mode of operation of the “engine – VFD” system, it is possible only until the demagnetization of the motor, and this doesn`t exceed several seconds for powerful motors. "
I'll bet here. Advance AT27 has a small but extremely valuable feature - the permanent magnetization of the motor in the process of lowering the frequency, which significantly extends the "survivability" and allows you to wait for the restoration of power supply.
Advance work of the AT27 is the key to reliable and non-stop operation of your technological process, even with a complete loss of input voltage!