Basic HTML Version
SOP4 – IMAC Instrumentation
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Ballast Cycle is selected from Piping screen – users cannot affect Sample Cycle from
Piping screen
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Sample Cycle is selected from Sample Screen – users cannot affect Ballast Cycle from
the Sample Screen
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Both Ballast and Cycles are displayed on
both
Piping and Sampling Screen
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Selected cycle is shown as a gradient gray/white, unselected cycles are shown solid light
gray
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Whenever Ballast and Sampling Cycles are not the same, buttons represented by selected
Ballast and Sampling Cycle (on both Piping and Sampling Screens) blink red/gradient
gray to note the ‘mismatch’
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Ballast and Sampling cycle selections on both Piping and Sampling Screen are confirmed
by a dialog box
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The disposition of the telegraph selection from both the Piping and Sample screens are
logged to the database, but the Piping screen telegraph selection is uniquely treated as
representative of the operator’s intent, such that differences in the expected valve line up
and the actual valve line up during a sampling event are automatically noted in event
reports.
5.3.3. Pump Controls
Both ballast pumps shall be operated from the HMI. They can be controlled in two ways – flow
control mode or RPM mode. A switch on the pump control groups located on the Piping screen
and the Pump screen allows users to toggle between the two modes. While in flow control
mode, the user sets/adjusts a set point representing a desired flow rate, and the system modulates
the pump to maintain that flow rate at the system flow meter associated with that pump. When
in RPM mode, the user sets/adjusts a set point representing a desired pump RPM, and the system
will operate the pump at that speed without regard to flow rate.
Adjustments to the set point are made using screen control buttons which raise or lower the set
point. These controls are represented as up and down arrows next to the set point display. The
flow set point is always displayed in cubic meters per hour (i.e. the units are not selectable
between metric and standard units).
The system will transition from flow control to RPM mode (and vice versa) in a bumpless
fashion. Functionally, the system will set the RPM set point to be equal to the current pump
RPM when switching from flow control to RPM mode, and set the flow control set point to be
equal to the current measured flow rate when switching from RPM mode to flow control mode.
The system shall also feature remote control of the Mud Proportioning Pump. A Mud Pump
Control group shall be included on both the Piping and Pump screens which shall feature remote
start/stop of the pump, and a pump speed control scheme similar to that described above for the
main ballast pumps. Users shall be able to set and adjust the speed of the Mud Pump using
incremental increase and decrease buttons. The Mud Pump control group shall also offer
indications of actual motor speed (expressed as frequency in Hertz), actual motor load, and
digital status indicators for local/remote operation, Running/Stopped status, and Fault Status.