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CAPITAL CONTROLS’ CAPTROL® Series 1451 Controller offers a host of features that make it uniquely suited to control schemes using two inputs such as disinfection,oxidation, and water quality monitoring and control. The standard output provides a 4-20 mA signal to control a broad range of chemical feed applications.Microprocessor-based digital electronics and digital alphanumeric displays simplify setup and operation. 

Microprocessor-based electronics automatically adjust a control valve or metering pump to maintain desired feed rates based upon input signals from the plant flow meter and/or residual analyzer, or water quality monitor. User-configurable control modes specific o automating chlorination, ammoniation water treatment applications, include flow proportioning, residual and compound loop control. For dechlorination with sulfur dioxide, dual input feed-forward control with an internal multiplier is available.


Push-button switches, conveniently located on the front panel, provide for rapid setup and simplified operation including manual positioning of the control valve or metering pump. Field conversion to any  control mode is accomplished by simple push-button mode commands selected. An internal battery protects setup parameters up to four days in the event of a power failure.


Control range adjustment of dosage (loop gain) on the flow input signal extends upwards to a ratio of 4:1 or down to zero permitting accommodation of an oversized flow meter, control valve, or metering pump. Dosage adjustment is automatic in the compound loop.

• Microprocessor-based
• Alphanumeric display data
• Fully field configurable
• Single loop backup in compound loop control
• Control with a long lag time

Microprocessor-based control provides precise control around a set point in compound loop by automatically adjusting process lag time for a change in flow rates. It also provides uninterrupted operation in the event that one compound loop input signal is lost by automatically transferring to single-loop control.
LED alarm indicators, mounted on the front panel for easy viewing, alert the operator to conditions of low or no plant water flow, and high or low deviation of residual beyond limits preset by the operator. Each alarm includes relay contacts for control of remote warning and control devices.
In a gas feed system, safe operation is enhanced through the provision of a discrete input for connection of high/low vacuum switches which close the control valve and cutoff gas feed, after a 30-second time-out, in the event of abnormal vacuum conditions. For plants requiring a backup operation, a duty/standby discrete switch input provides for operator selection of the active and backup system.

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