Step 4 of the Six Steps to Optimizing your compressed air is to turn off your compressed air when it is not in use. This step can be done using two simple methods either by using manual controls such as ball valves or automated controllers such as solenoid valves. Manual controls are designed for long use and when switching on and off are infrequent. Ball Valves are one of the most commonly used manual shut offs for compressed air and other fluids.
Automated controllers allow your air flow to be tied into a system or process and turn on or off when conditions have been met. Solenoid valves are the most commonly used automated control device as they operate by using an electric current to open and close the valve mechanism within. Solenoid valves are some of the more versatile flow control devices due to the fact that they open and close almost instantaneously. Solenoid valves can be used as manual controls as well by wiring them to a switch or using simple programming on a PLC to turn the valve on or off using a button.
Some good examples of automated controllers are EXAIR’s Electronic Flow Controller (a.k.a. EFC) and EXAIR’s Thermostat controlled Cabinet Coolers.
The EFC system uses a photo eye to detect when an object is coming down the line and will turn on the air for a set amount of time of the users choosing. This can be used to control the airflow for all of EXAIR’s products. EXAIR’s Thermostat controlled Cabinet Coolers are used to control the internal temperature of a control cabinet or other enclosures. This is done by detecting the internal temperature of your cabinet and when it has exceeded a temperature which could damage electrical components it will open the valve until a safe temperature has been reached, then turn off.
By turning off your compressed air, whether it be with manual or automated controllers, a company can minimize wasted compressed air and extend the longevity of the air compressor that is used to supply the plants air. The longevity of the air compressor is increased due to reduced run time since it does not need to keep up with the constant use of compressed air. Other benefits include less use of compressed air and recouped cost of compressed air.
If you have questions about our compressed air control valves or any of the 16 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.
Cody Biehle Application Engineer EXAIR Corporation Visit us on the Web Follow me on Twitter Like us on Facebook
One of the most important aspect of an efficient compressed air delivery system is effective utilization of compressor controls. The proper use of compressor controls is critical to any efficient compressor system operation. In order to reduce operating costs, compressor controls strategies need to be developed starting with minimizing the discharge pressure. This should be set as low as possible to keep energy costs to a minimum.
The compressor system is designed with maximum air demand in mind. During periods of lower demand compressor controls are used to coordinate a reduction in output that matches the demand. There are six primary types of individual compressor controls:
Start/Stop – This is the most basic control. The start/stop function will turn off the motor in response to a pressure signal.
Load/Unload – The motor will run continuously, but the compressor unloads when a set pressure is reached. The compressor will then reload at a specified minimum pressure setting.
Modulating – Restricts the air coming into the compressor to reduce compressor output to a specified minimum. This is also known as throttling or capacity control.
Dual/Auto Dual – On small reciprocating compressors, this control allows the selection of either Start/Stop or Load/Unload.
Variable Displacement – Gradually reduces the compressor displacement without reducing inlet pressure.
Variable Speed – Controls the compressor capacity by adjusting the speed of the electric motor.
Most compressor systems are comprised of multiple compressors delivering air to a common header. In these types of installations, more sophisticated controls are required to orchestrate the compressor operation. Network controls link together each compressor in the system to form a chain. Usually, one compressor will assume the lead role with the others taking commands from the primary compressor. Some disadvantages of network controls include: only having the ability to control the compressors, cannot be networked with remote compressor rooms without a master control, and they generally only work well with compressors of the same brand due to microprocessor compatibility issues.
In more complicated systems, master controls can be used to coordinate all of the necessary functions to optimize the compressor system. Master controls have the ability to monitor and control all of the components within the system. The high-end master control systems utilize single point control logic with rate of change dynamic analysis in order to determine how the system will respond to changes. Changes on the demand side, supply side, or the ambient environment will all impact a compressor’s performance. An effective master control will be able to identify these changes and provide the most energy efficient response.
At the point of use, it’s always important to ensure you’re using a product that was engineered to reduce compressed air consumption. EXAIR’s line of Intelligent Compressed Air Products are available from stock to help you manage your overall operating costs.