Why Bus is Better: In conventional installations a bundle of power and signal wires is run from the PLC or control station to each actuator. For example, an electric actuator with just two auxiliary limit switches could have as many as 9 wires run to it. Multiply that by the number of actuated valves in the system and you can see how complex it can get. And the more features the actuator has the more wires that have to be connected to it. In multiple automated valve applications the number of wires can run into the hundreds.
Real Cost Savings: The industry standard cost for discreet wiring (design, conduit, wire, installation etc.) is $8.00 per foot, versus $2.00 per foot with Bus Technology. In a system with 20 actuators installed an average of 200 feet from the PLC, the installation cost savings would be $24,000 for a system using Hayward's Bus Technology. And remember that this is just the savings on the installation cost alone. Think of what it will cost to maintain and troubleshoot a maze of hundreds of individual wires, a cost that would not exist with Hayward's Bus Control System.
Application Flexibility: Applications that are well along in the design stage can still take advantage of Hayward's Bus Control System. In both a conventional and Bus system installation, the computer interfaces with a PLC. The PLC simply sequences the operation of valves and is already commonplace in most multiple valve systems. Therefore, there are no significant changes required to the main control station to take advantage of Hayward's Bus Technology.
Communication Protocols: Hayward Bus Technology also takes into account the different communications protocols required by PLC's from different manufacturers. In basic on/off applications the system "understands" all PLC's no matter what communications protocols the PLC uses: PROFIBUS, Modbus, Field Bus or others. And for modulating applications, Hayward can modify the Bus Control System for the specific communications protocol required by the PLC.
Electric or Pneumatic Automation: Hayward Bus Control Systems work with Hayward EVS Series Electric Actuators and Hayward Series PH or PK Pneumatic Actuators. The module for the electric actuator fits inside the actuator housing. The one for the pneumatic actuators is contained in a small housing that mounts directly to the actuator and provides power as well as signal to the actuators.
Pneumatic Bus Module Features: This module is housed in a transparent, screw on Lexan® housing that is rated NEMA 4, 4X and IP67. The large color coded visual indicator clearly displays the percentage that the valve is open or closed. Solid state inductive sensors located inside the enclosure provide reliable and accurate position sensing. This reduces wear on the mechanical switches and helps prolong their service life. The module features an integral solenoid valve and is available in brass or stainless steel construction. This solenoid is a high flow, low power consumption unit the pilot solenoid protected within the module enclosure. Solenoid power is provided directly form the AS-l or DeviceNet twisted pair, simplifying electrical connections. The module is available with a choice of either 120 VAC or 24 VDC operation and a manual override is standard on both. Auxiliary power must be provided to the solenoid for Foundation Fieldbus applications.
Electric Module Features: The electrical bus module is a plug-in type protocol module that allows for maximum flexibility. It mounts directly into the actuator housing and is completely contained within the housing. This eliminates the need for external additions to the actuator or any additional brackets. Several different protocol modules are available to handle all applications parameter requirements.
