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STATION MASTERª 2000 Engineering Specifications
This specification covers a complete and operational automatic duplex pump control and alarm system responding to the ________________ level as shown on the plan drawings.
The controller shall accept a single analog input signal over a user definable, field configurable range. To reduce exposure to corrosive environments and ensure the control system's reliable, long-term operation, the controller shall have a sealed, user-friendly, graphical interface. The interface shall be comprised of a rotary knob, switches and five columns of ultra-bright, daylight-viewable red LEDs. Four 40-segment, 4" columns of LEDs shall show the process tank level, the pump on and off control bands, and the high and low alarm setpoint bands. All LEDs within a control band shall be illuminated when operating under normal power. A fifth LED column shall indicate the controller's configuration, status, and active alarms. Alarms shall consist of high alarm, low alarm and input signal out of range. Monitor functions shall include control power and normal system operation. The controller shall contain an internal annunciator and an external alarm driver that activate on an alarm condition. The controller shall contain an integral 'silence' key and an external silence input. Discrete LEDs shall show the activation of the differential pump control stages.
The controller shall provide easy, convenient indication and adjustment of the operating setpoints and controller configuration without the need for tools. For ease of operation and configuration, multiple indicating columns are required. Controllers that provide fewer columns, thus limiting the viewing of relevant and necessary station information, are specifically precluded by this specification.
The control circuits shall be forced OFF by activation of the external inhibit input or upon power loss. Upon power restoration, or removal of the inhibit input, the controller shall enable its outputs in an adjustable time-step sequence as required to meet the demand.
The controller shall continuously indicate the status of the selected alternation sequence, pumping direction, and control modes. The controller shall provide 1st On/1st Off, Fixed, and Auto Rotate alternation sequences and selectable Pump-Up or Pump-Down programming.
Integral span, offset, and damping adjustments shall be easily adjustable. The controller shall have the ability to select from 1 to 40 seconds of input signal averaging/damping. The controller shall have a configurable security lockout feature.
The controller shall be powered by 12-30 VDC. When operating on main power, the controller shall charge an optional, external electrolyte gel-cell battery. Upon loss of power, and when provided with the battery, the controller shall revert to a low-power mode. When applied as an RTU and operating on battery backup, the controller shall continue to provide communication with the host controller.
The controller shall contain a level simulation function that allows manual manipulation of the displayed process variable. While simulating, the controller shall display both the actual process level and the simulated level.
The controller shall provide isolated 5 and 24 VDC for direct power/excitation of a compatible level sensing transducer. The controller shall contain a galvanically isolated analog input, two optically isolated digital inputs, and five digital outputs. The analog input shall accept a nominal 0-5 VDC or 4-20 mADC signal. Three digital outputs shall be individually fused solid-state switches with zero-voltage turn-on and zero-current turn-off. Two discrete outputs shall be provided for common alarm and controller monitor. The controller shall contain an RS-232 communication port and have capabilities for connection to a SCADA (Supervisory Control And Data Acquisition) system. The complete assembly shall be designed for use in UL508 Industrial Control Panels. All job connections shall be at drop-cage type removable terminals.
It is the specific intention of this functional requirement that a standard controller shall be provided with features as described herein. Additionally, this controller shall be a fully-integrated assembly. That is, the furnishing of similar functions using multiple setpoint modules, a custom-configured programmable logic controller (PLC) or extensive relay/timer logic to accomplish control sequences, etc., is specifically precluded by this specification and is not acceptable. The controller shall be a Contegra STATION MASTER 2000.