Programmable logic controllers (PLC’s) and human-machine interfaces (HMI) are the cornerstones of modern automation. These systems serve as the brains of an industrial machine and ensure the various aspects of the machine are running correctly. Depending on the size of the machine, several large PLC’s might be used or just one on a much smaller machine. These critical devices can become very expensive, so it is important to select the proper one for your machine.
In this blog, we would like to explore a somewhat newer technology that is designed to save money. A variable frequency drive, or VFD, is designed to control the speed of an electric motor to match the immediate needs of an application. Many of these motors operate at 100% speed all the time even if it is not necessary. A VFD is used to alter the total amount of energy being sent to the motor by monitoring various inputs and determining whether to increase or decrease the amount of energy being sent to a motor.
For example, if you are running a machine and need to pump coolant throughout it, then the pump motor may run continuously at 1,000 RPM. However, if production has slowed or if the machine is operating much cooler than usual then running the motor at that rate is wasteful. Placing VFD within the system, along with other sensors, will determine if the pump needs to be slowed down and automatically adjust the energy being sent to the motor. During slower production times, the pump motor may be reduced to only 600 RPM thereby saving energy.
The great thing about motors is that the energy savings are non-linear, meaning that a reduction of speed from 1,000 RPM to 600 does not reduce energy consumption by 40%. There is a cubic relation to energy savings meaning that a VFD placed in the system will consume 60% x 60% x 60% = 22% of energy than at 1,000 RPM. For this scenario, the VFD will save nearly 80% of the money spent on energy when running at a reduced speed (detailed article here).
When motors are designed into a system, one is selected that is powerful enough to handle the largest task or load. Basically, it is done to make sure the motor is not met with a significant challenge. Without a motor controller of some kind, the system will run full speed even if it is excess. Most of the time it is probably not necessary and therefore wastes energy and, therefore, money.
The importance of a VFD system is how it helps save significant money over time. Efficiencies produced by the VFD are such that the system will likely pay for itself in a relatively short amount of time. The primary areas of savings come from a reduction of:
- Energy consumption of the system itself
- Maintenance needs because the VFD protects the mechanical function of the motor
- Downtime as the system can ensure speed adjustments for the operation.
MISUMI is proud to announce our partnership with Mitsubishi Electric Automation in the North American market. We are the first e-catalog industrial supplier to offer Mitsubishi so that customers can get a quote and place an order directly on our website. This saves customers time by ensuring fast access to crucial lead time and pricing information.
While MISUMI aims to save customers valuable time, Mitsubishi is focused on saving customers money with their products. While they offer some of the best PLCs, HMIs, encoders and other industrial products, their VFDs are also designed to reduce energy consumption.
Thinking about adding a VFD to your production line? MISUMI offers the very best VFD’s from Mitsubishi Electric Automation. We are also a one-stop-shop to install a VFD system as we offer high-quality Belden VFD cable to ensure peak performance and various types of motors.