Features
Automated PLC control system	Visual Indication of complete system with animation
Simultaneous control of valves & tank levels	Automatic calibration of valve Indicators
Local & remote control stations with safety interlocks	Upgradable to include Unloading Control, Engine monitoring & additional shipboard auxiliary systems.

Reliable and accurate ballast tank level measurement and control is important to the safe and efficient operation of a ship. The Marsh ballast level gauging system uses state of the art electronics coupled with the tried and true bubbler measurement system to provide cost effective, accurate and reliable level information and control to the ballast operator in a timely and effective manner.

The Human Machine Interface (HMI) consists of a number of custom designed screens displayed on two monitors that provide the Operator with information and allow them to ballast the ship. Following are the major screens:

Overview screen Overview 1 PORT side STBD side Overview 2 Discharge screen

Suction Screen Main Control Screen Strip control Screen Alarm Setup Screen

The Overview screen provides the Operator with a summary of the status of the levels and valve positions for the ship. This screen is designed to provide a quick visual indication of the levels of all the tanks as a bar chart and to identify any tanks in level alarm by means of color change. The Overview screen also shows the status of the Main and Stripping tank valves as colored boxes above each tank. If a valve is more than 5% open, the box displays "M" or "S" depending upon the Main and Stripping valve with yellow back round, otherwise the box is gray. This allows the Operator to quickly identify any open (i.e. not closed) tank valves. The overview screen consists of overview 1 & 2. Overview 1 displays both PORT & STBD side, by clicking anywhere on the picture takes you to the corresponding PORT or STBD side screen. Overview 2 screen displays the same information in full size bar chart.

The Discharge and Suction screens are similar in function and presentation. The Discharge screen displays data relating to the PORT & STBD side discharge function of the ship while the Suction screen displays data relating to the PORT & STBD side suction function of the ship. Each of the screens includes a number of indicators and control switches providing tank levels, valve position & status & valve control to open / close the valves.

The Main Control screen displays data relating to the PORT & STBD side Discharge ballast pump control while Strip control displays the data relating to the Suction ballast pump control. Each of the screens includes a number of valve indicators and associated control switches for each valve. The valves with long traveling time such as overboard Discharge, Sea suction and Crossover valves has a feature of being automatic open and close. By pressing ONCE the 90 % OPEN button of the associated valve will open the valve automatically until it reaches 90 % open. Similarly the valve is 90 % closed by pressing ONCE the 90 % CLOSE button. For safety reason, this automatic latching can be stopped any time by pressing the STOP button or the opposite action button. i.e. Automatic opening of the valve can be stopped either by pressing the STOP button or pressing the CLOSE button of the associated valve.

The Alarm Setup screen allows the Operator to easily adjust the alarm setpoints for the tank levels.

Part of this basic package, Marsh includes the new Calibration feature, each valve indicators can be calibrated to display 0 to 100 % regardless of potentiometer setting or voltage level of the valves and it is performed from the remote computer.

Please contact our system integration group for more details & to arrange a demo.

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