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Systems Engineering 13-17

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How accessible should the controls be?

Over-engineering or over-design should be avoided. This serious and costly mistake can be

made by engineers and company staff when planning technical system requirements. A staff
member may, for example, ask for a seemingly simple feature or capability without fully under-
standing its complexity or the additional cost burden it may impose on a project. Other portions
of the system may have to be compromised in order to implement the additional feature. An
experienced systems engineer will be able to spot this type of issue and determine whether the
tradeoffs and added engineering time and cost are really justified.

When existing equipment is going to be used, it will be necessary to make an inventory list.

This list will be the starting point for developing a final equipment list. Usually, confronted with
a mixture of acceptable and unacceptable equipment, the systems engineer must sort out what
meets current standards and what should be replaced. Then, after soliciting input from facility
technical personnel, the systems engineer develops a summary of equipment needs, including
future acquisitions. One of the systems engineer's most important contributions is the ability to
identify and meet these needs within the facility budget.

A list of major equipment is prepared. The systems engineer selects the equipment based on

experience with the products, and on customer preferences. Often some of the existing equip-
ment may be reused. A number of considerations are discussed with the facility customer to
arrive at the best product selection. Some of the major points include:

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Budget restrictions

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Space limitations

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Performance requirements

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Ease of operation

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Flexibility of use

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Functions and features

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Past performance history

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Manufacturer support

The goal here is the specification of equipment to meet the functional requirements of the project
efficiently and economically. Simplified block diagrams for the video, audio, control, data, and
communication systems are drawn. They are discussed with the customer and presented for
approval.

13.1.3c

Detailed Design

With the research and preliminary design development completed, the details of the design must
now be concluded. The design engineer prepares complete detailed documentation and specifi-
cations necessary for the fabrication and installation of the technical systems, including all major
and minor components. Drawings must show the final configuration and the relationship of each
component to other elements of the system, as well as how they will interface with other building
services, such as air conditioning and electrical power. This documentation must communicate
the design requirements to the other design professionals, including the construction and instal-
lation contractors.

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Systems Engineering

13-18 Standards and Practices

In this phase, the systems engineer develops final, detailed flow diagrams and schematics that

show the interconnection of all equipment. Cable interconnection information for each type of
signal is taken from the flow diagrams and recorded on the cable schedule. Cable paths are mea-
sured and timing calculations are made for signals requiring synchronization, such as video, syn-
chronizing pulses, subcarrier, and digital audio and/or video (when required by the design).
These timed cable lengths are entered onto the cable schedule.

The  flow diagram is a schematic drawing used to show the interconnections between all

equipment that will be installed. It is different from a block diagram in that it contains much
more detail. Every wire and cable must be included on the drawings.

The starting point for preparing a flow diagram can vary depending upon the information

available from the design development phase of the project, and on the similarity of the project to
previous projects. If a similar system has been designed in the past, the diagrams from that
project can be modified to include the equipment and functionality required for the new system.
New models of the equipment can be shown in place of their counterparts on the diagram, and
only minor wiring changes made to reflect the new equipment connections and changes in func-
tional requirements. This method is efficient and easy to complete.

If the facility requirements do not fit any previously completed design, the block diagram and

equipment list are used as a starting point. Essentially, the block diagram is expanded and details
added to show all of the equipment and their interconnections, and to show any details necessary
to describe the installation and wiring completely.

An additional design feature that might be desirable for specific applications is the ability to

easily disconnect a rack assembly from the system and relocate it. This would be the case if the
system where to be prebuilt at a systems integration facility and later moved and installed at the
client's site. When this is a requirement, the interconnecting cable harnessing scheme must be
well planned in advance and identified on the drawings and cable schedules.

Special custom items need to be defined and designed. Detailed schematics and assembly dia-

grams are drawn. Parts lists and specifications are finalized, and all necessary details worked out
for these items. Mechanical fabrication drawings are prepared for consoles and other custom-
built cabinetry.

The design engineer provides layouts of cable runs and connections to the architect. Such

detailed documentation simplifies equipment installation and facilitates future changes in the
system. During preparation of final construction documents, the architect and the design engi-
neer can firm-up the layout of the technical equipment wire ways, including access to flooring,
conduits, trenches, and overhead wire ways.

Dimensioned floor plans and elevation drawings are required to show placement of equip-

ment, lighting, electrical cable ways, duct, conduit, and HVAC ducting. Requirements for special
construction, electrical, lighting, HVAC, finishes, and acoustical treatments must be prepared
and submitted to the architect for inclusion in the architectural drawings and specifications. This
type of information, along with cooling and electrical power requirements, also must be provided
to the mechanical and electrical engineering consultants (if used on the project) so they can begin
their design calculations.

Equipment heat loads are calculated and submitted to the HVAC consultant. Steps are taken

when locating equipment to avoid any excessive heat buildup within the equipment enclosures
while maintaining a comfortable environment for the operators.

Electrical power loads are calculated and submitted to the electrical consultant and steps

taken to provide for sufficient power, proper phase balance, and backup electricity as required.

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Systems Engineering

Systems Engineering 13-19

13.1.3d Customer Support

The systems engineer can assist in purchasing equipment and help to coordinate the move to a
new or renovated facility. This can be critical if a great deal of existing equipment is being relo-
cated. In the case of new equipment, the customer will find the systems engineer's knowledge of
prices, features, and delivery times to be an invaluable asset. A good systems engineer will see to
it that equipment arrives in ample time to allow for sufficient testing and installation. A good
working relationship with equipment manufacturers helps guarantee their support and speedy
response to the customer's needs.

The systems engineer can also provide engineering management support during planning,

construction, installation, and testing to help qualify and select contractors, resolve problems,
explain design requirements, and assure quality workmanship by the contractors and the techni-
cal staff.

The procedures described in this section outline an ideal scenario. In reality, management

may often try to bypass many of the foregoing steps to save money. This, the reasoning goes, will
eliminate unnecessary engineering costs and allow construction to start right away. Utilizing in-
house personnel, a small company may attempt to handle the job without professional help. This
puts an added burden on the staff who are already working full time taking care of the daily oper-
ation of the facility. With inadequate design detail and planning, which can result when using
unqualified people, the job of setting technical standards and making the system work then
defaults to the construction contractors, in-house technical staff, or the installation contractor.
This can result in costly and uncoordinated work-arounds and—of course—delays and added
costs during construction, installation, and testing. It makes the project less manageable and less
likely to be completed successfully.

The complexity of a project can be as simple as interconnecting a few pieces of equipment

together to designing the software for an automated robotic storage system. The size of a techni-
cal facility can vary from a small one room operation to a large multimillion dollar facility.
Where large amounts of money and other resources are going to be involved, management is well
advised to recruit the services of qualified system engineers.

13.1.3e

Budget Requirements Analysis

The need for a project may originate with customers, management, operations staff, technicians,
or engineers. In any case, some sort of logical reasoning or a specific production requirement
will justify the cost. On small projects, like the addition of a single piece of equipment, money
only has to be available to make the purchase and cover installation costs. When the need may
justify a large project, it is not always immediately apparent how much the project will cost to
complete. The project has to be analyzed by dividing it up into its constituent elements. These
elements include:

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Equipment

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Materials

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Resources (including money and man hours needed to complete the project)

An executive summary or capital project budget request containing a detailed breakdown of
these elements can provide the information needed by management to determine the return on
investment, and to make an informed decision on weather or not to authorize the project.

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Systems Engineering

13-20 Standards and Practices

A capital project budget request containing the minimum information might consist of the

following items:

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Project name. Use a name that describes the result of the project, such as “control room
upgrade.”

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Project number (if required). A large organization that does many projects will use a project
numbering system of some kind, or may use a budget code assigned by the accounting depart-
ment.

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Project description. A brief description of what the project will accomplish, such as “design
the technical system upgrade for the renovation of production control room 2."

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Initiation date. The date the request will be submitted.

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Completion date. The date the project will be completed.

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Justification. The reason the project is needed.

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Material cost breakdown. A list of equipment, parts, and materials required for construction,
fabrication, and installation of the equipment.

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Total material cost.

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Labor cost breakdown. A list of personnel required to complete the project, their hourly pay
rates, the number of hours they will spend on the project, and the total cost for each.

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Total project cost. The sum of material and labor costs.

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Payment schedule. Estimation of individual amounts that will have to be paid out during the
course of the project and the approximate dates each will be payable.

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Preparer's name and the date prepared.

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Approval signature(s) and date(s) approved.

More detailed analysis, such as return on investment, can be carried out by an engineer, but

financial analysis should be left to the accountants who have access to company financial data.

Feasibility Study and Technology Assessment

In the case where it is required that an attempt be made to implement new technology, and where
a determination must be made as to weather certain equipment can perform a desired function, it
will be necessary to conduct a feasibility study. The systems engineer may be called upon to
assess the state-of-the-art in order to develop a new application. An executive summary or a
more detailed report of evaluation test results may be required, in addition to a budget estimate,
in order to help management make their decision.

Planning and Control of Scheduling and Resources

Several planning tools have been developed for planning and tracking progress toward the com-
pletion of projects and scheduling and controlling resources. The most common graphical
project management tools are the Gantt Chart and the Critical Path Method (CPM) utilizing the
Project Evaluation and Review (PERT) technique. Computerized versions of these tools have
greatly enhanced the ability of management to control large projects.

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Systems Engineering

Systems Engineering 13-21

13.1.3f

Project Tracking and Control

A project team member may be called upon by the project manager to report the status of work
during the course of the project. A standardized project status report form can provide consistent
and complete information to the project manager. The purpose is to supply information to the
project manager regarding work completed, and money spent on resources and materials.

A project status report containing the minimum information might contain the following

items:

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Project number (if required)

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Date prepared

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Project name

•

Project description

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Start date

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Completion date (the date this part of the project was completed)

•

Total material cost

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Labor cost breakdown

•

Preparer's name

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Change Control

After part or all of a project design has been approved and money allocated to build it, any

changes may increase or decrease the cost. Factors that effect the cost include:

•

Components and materials

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Resources, such as labor and special tools or construction equipment

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Costs incurred because of manufacturing or construction delays

Management will want to know about such changes, and will want to control them. For this

reason, a method of reporting changes to management and soliciting their approval to proceed
with the change may have to be instituted. The best way to do this is with a change order request
or change order. A change order includes a brief description of the change, the reason for the
change, a summary of the effect it will have on costs, and what effect it will have on the project
schedule.

Management will exercise its authority and approve or disapprove each change based upon its

understanding of the cost and benefits, and their perceived need for the modification of the orig-
inal plan. Therefore, it is important that the systems engineer provide as much information and
explanation as may be necessary to make the change clear and understandable to management.

A change order form containing the minimum information might include the following items:

•

Project number

•

Date prepared

•

Project name

•

Labor cost breakdown

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Systems Engineering