18 August 1998
10. SYSTEM CONFIGURATION.
a. The total number of I/O points estimated for all systems establishes a starting point for
determining the relative size of the UMCS. System hardware configuration will follow the guidelines
established in Chapters 3 and 4. The number of field equipment panels will be determined by:
The number of I/O points per system.
The maximum number of I/O points per field equipment panel.
b. User requirements will be evaluated to determine the need for Central/Island Station backup
operation or the need for operator workstations in multiple locations. The final system configuration to be
documented in the contract drawings and specifications will be determined as part of the design process.
c. Once the configuration of the UMCS has been established, the location of the Central Station and
Island Stations will be determined. The location of the Central Station and Island Stations is influenced
by the location of the physical plant operating personnel, availability of communication media, available
space and power, and future applications. The Central Station and Island Stations will not be located in
close proximity to large electrical loads, rotating machinery or other sources of vibration, or in dirty air
d. After the locations of the Central Station and Island Stations have been established, the
placement and minimum required quantity of field equipment panels and the data transmission system
requirements and routing will be determined.
11. DATA COMMUNICATION CONSIDERATIONS. The data transmission equipment selection and
communication media layout will be coordinated with the communications office for review and comments
in accordance with the guidelines described in Chapter 10. The data transmission system configuration
will be clearly defined in the contract documents. Data transmission system installation and maintenance
costs, coordinated with the communications office, will be used in preparing the cost estimate. The
selection of the data transmission system will be based on a life-cycle cost analysis of data transmission
system types using current cost data for their installation and maintenance. The topology of the data
transmission system and the detailed layout will be based on the guidelines presented in Chapter 10.
12. INTERCOMMUNICATIONS. The designer will determine whether the facility operating personnel
require an intercommunication system in conjunction with the UMCS. Hand held FM transceivers may, in
many cases, be used as an intercom system. An intercommunication system will require a dedicated pair
of wirelines or optical fibers from the Central Station/Island Station to each intercom station in addition to
UMCS communication media.
13. FIELD HARDWARE LOCATION. The location of field equipment panels will be determined in
accordance with the following guidelines:
a. Field equipment panel locations will be outside the equipment rooms, where practicable, and
selected such that the ambient conditions are between 50 degrees F and 90 degrees F and 10 to 85
percent relative humidity. Field equipment panels located in areas exceeding these ranges will have
enclosures with heating or cooling devices to provide the proper environmental conditions.
b. Field equipment panels will be located within close proximity to equipment rooms in order to
minimize field wiring.
14. EQUIPMENT MODIFICATIONS.