Walchem WCT400 Series Instruction Manual

Walchem WCT400 Series Instruction Manual Manual pdf 4 page image

11.0 INTRODUCTIONThe Walchem WCT400 Series controllers offer conductivity and watermeter-based control of coolingtower water, control of corrosion/scale inhibitor feed, and with the WCT410 models, control of twobiocide pumps. The inhibitor pump may be selected to operate in one of the following modes:Feed and BleedFeed and Bleed with LockoutFeed as a percent of BleedFeed as a percent of TimeFeed based on a Water Contactor inputFeed based on a Paddlewheel water meter inputThe WCT series cooling tower controllers are supplied with a temperature compensated carbonelectrode with a cell constant of 1.0. The controllers are microprocessor driven industrial type withon/off control outputs. A timed sample mode may be selected, and on small towers can reduceinstallation costs by eliminating the need for a sampling bypass line. An optional isolated 4-20 mAoutput that is proportional to the conductivity reading is available for all models.Any set point may be viewed without interrupting control. Each set point change will take effect as soonas it is entered. An access code is available to protect set point parameters, while still allowing settingsto be viewed.The model WCT410 biocide outputs are scheduled on a user selectable 1, 2, or 4 week cycle. Eachbiocide output is independent and may be programmed for one add per day. (in 1, 2 or 4 week cycle) orup to 10 times per day (in daily cycle). It is possible to add both chemicals in the same day, however, asa safeguard they will not occur at the same time. Biocide outputs may use independent pre-bleeds andlockout times. All outputs are interlocked with a flow switch input.An alarm relay is provided with WCT410 models. It is triggered by:Low Conductivity readingHigh Conductivity readingNo Flow situationBleed TimeoutSensor ErrorTemp ErrorOur unique USB feature provides the ability to upgrade the software in the controller to the latestversion.An advanced USB capability option is available. The Config file feature allows you to save all the setpoints from a controller onto a USB flash disk, and then import them into another controller, making theprogramming of multiple controllers fast and easy. The data logging feature allows you to save the last2 month’s readings and events to a USB flash disk.