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Bay Compressor Controller vs. OEM Controllers
Clearly Superior
At Bay Controls, we believe we offer the best compressor control system on the market. When compared to the OEM Controllers there really is no comparison – the Bay system is clearly superior in every important control category. When it comes to performance, reliability, energy efficiency and system management, the better controller is the Bay product.
To understand the root of why Bay systems are better, it is important to grasp a key concept: in the world of compressors, Bay Controls is a control technology company, while the OEM’s primary focus is on compressor manufacturing. The difference is crucial. Bay has spent decades refining its control products and innovating new control features; the result is that no company can offer a better compressor control solution.
The Details
A Bay control system really does outperform an OEM Controller in just about every important measurement. Here are some of the more compelling differences between the two systems:
Pressure Control: One key objective of the Bay control strategy is to maintain a constant pressure setpoint in the plant air header, as close to the final point of use as possible. The OEM’s strategy instead maintains a constant pressure at the compressor discharge. The Bay method results in tighter pressure regulation of the compressed air system, allowing the operating pressure to be lower without risk of plant upset. Often an OEM controlled plant air system varies 5 to 10 psi as the demand for air fluctuates. After retrofitting the compressors with Bay controllers, the same plant can operate with less than 1.0 psi variance in plant pressure.
Additionally, since many OEM Controllers read and react to individual discharge pressure, the pressure measured is often different for each compressor. As a result, separate controllers actually may be unloading and loading their compressors at the same time. The system may never stabilize as the controls continue to counteract each other, reacting artificially to each others control actions instead of true changes in plant demand. The resulting inefficiencies can add 2% to the total energy cost of the compressor system. By design, the Bay approach – measuring actual system pressure and modulating a single compressor at a time – never suffers from this counterproductive condition.
Anti Surge Control: The Bay anti-surge control function uses the relationship of mass flow and polytrophic head to predict the surge point under all operating conditions. Since every compressor has slightly different operating characteristics, this function is precisely tuned for each unit in a system. The result is an accurate model of the compressor’s surge curve, which means that a Bay controlled compressor will provide the maximum throttle range without surge while operating at any discharge pressure and any inlet temperature and pressure condition. The OEM Controllers use a simple fixed minimum flow setpoint based on motor current. Bay controlled compressors usually have double the throttle range, without blow-off or surge, when compared to typical OEM installed controls. Depending on plant demand and system operating characteristics, this major improvement in minimum throttle (and thus reduced blowoff) can result in substantial energy savings.
Distributed Capacity Control: When a multiple compressor system is involved, the Bay distributed capacity control (DCC) method is more efficient than the OEM Controllers load sharing approach. With OEM load sharing, each compressor is throttled equally, which mean that it is rare for any compressor to operate at its most efficient setting. In comparison, with the Bay DCC approach, one compressor modulates its load while all other compressors are operated at their maximally efficient full load state. In a system with three or more compressors operating simultaneously, Bay’s distributed capacity control can save up to 2% of the system’s energy costs.
DCC Reliability: The Bay Controls DCC system is designed with reliability as a central feature. Using a redundant multi-master system means that any Bay compressor controller can assume command of the DCC system at any time. If the current Leader controller cannot properly perform the leadership function (due perhaps to a communication problem or faulty system pressure transmitter), one of the other controller’s in the network will automatically assume command.
Compare this to the typical OEM controller, which uses a personal computer running Microsoft Windows or a dedicated master controller to direct the compressor network. If the master controller fails or needs to be restarted, all the individual OEM controllers revert to inefficient independent control. Clearly, the Bay approach is superior.
Network Flexibility: Bay systems are designed to work with all makes and models of air compressors. This flexibility allows all compressors in a system to operate under the same Bay control network and seamlessly participate in a distributed capacity control scheme. In contrast, many OEM controllers are designed only for centrifugal compressors, and requires additional equipment to interface with different compressor types.
Can they even network with non-OEM compressors?
Bay can and has controlled and networked every type of air compressor!
Management Productivity: Bay has developed a comprehensive set of control and management software products which complement the functionality of the control system. Whether it is an internal plant network, or an internet based solution, Bay network software offers unmatched levels of control, monitoring and data reporting. The OEM Controllers simply cannot offer the same amount of sophistication and capability in this area.
The Bottom Line
Real world examples prove that the Bay control system outperforms the OEM Controller. In cases where OEM systems have been replaced with Bay controllers, the resulting energy savings range from 8% to 15%. In today’s world of seemingly ever increasing energy prices, this amount of energy use reduction is substantial.
Our products not only save our customers money due to their superior features, but they also retain their value because they are designed to be compatible with future updates. Bay has a proven control strategy that has remained consistent for decades. In comparison, IR, Cameron, Atlas Copco, Elliot and other compressor OEMs seem to frequently change control approaches and hardware, requiring costly replacement of old systems when they suddenly become obsolete. A Bay system will be a productive part of any compressed air system for many years after installation.
Replacing an OEM Controller with a Bay control product is relatively simple. Typically, the Bay system installs in about a day and uses most of the existing instrumentation; an additional pressure transmitter to read plant pressure is often the only extra equipment needed.
In the final analysis, the OEM Controllers provide little beyond the essential controls needed to operate a centrifugal compressor. Bay offers a fundamentally different and more comprehensive approach, focusing on optimal operation of an entire compressor system in terms of precision, reliability, energy efficiency, management and return on investment.
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