General Provisions - Nuclear Power Plant Instrumentation and Control Systems for Safety and Security - page 20

The equipment family is usually oriented for
performance of a set of typical functions, which can
be selected, gathered in various combinations, and
customized according to tasks of the specific I&C
system. The design of hardware and application
software of SHC is supported by relevant tools
and supports software, recommended or supplied
by the еquipment family designer.
The equipment family can be a product of a
certain manufacturer or a set of items, gathered
and adapted by supplier. Marketing policy of
еquipment family designers can provide one or
several options of use for building SHC:

Having a set of aggregate modules, supporting
structures, basic programs, instrumentation tools
and typical methods, and using them during as-
sembling of SHC for various I&C systems, they
do not register and advertise this set (having all
features of equipment family) as a public platform,
using it only for development of their own SHCs .
Many companies actively use such an ap-
proach for meeting individual users' needs, build-
ing relevant equipment families. Development
was preceded by researches, which detect real
problems and needs of a certain group of users,
then on their basis technical requirements able
to efficiently meet these needs, are developed.
Due to the considered ideology, optimal set of
equipment and availability of all required types
of provisions, this platform is more valuable for
the end user, than a simple set of its components.
In the composition of equipment family more or
less external components are also used: standards,
technologies, design automation facilities, mar-
keting initiatives, infrastructure of tracking and
maintenance, etc. For platform will to gain a real
value, all its components should be compatible
and well combined with each other.
WDPF-II - equipment families of Westing-
house Electric Company intended for building
distributed I&C systems with a wide choice of
applied use. In WDPF-II a long experience of
development and operation of earlier generation
equipment in power units with Pressurized Wa-
ter Reactors (PWR), manufactured by the same
company, is accumulated.
Lower level is based on several operating
stand-alone devices- Distributed Processing
Units (DPU). Each DPU contains two redundant
microprocessor controllers and a set of input-
output modules of analog and discrete signals.
Controller is implemented on the basis of proces-
sor architecture IA-32 (Intel Corporation) and
contains microprocessor, flash-memory, random
access memory, watch dog. Input-output modules
are connected to both controllers. DPU captures
information about parameters of technological

• Delivery of separate items from the
equipment family; in this case integration
of equipment family components and adap-
tation of SHC for performance of speciied
functions (including, when required, com-
pleting a set with items of another manu-
facturer) are performed by the customer
(end user or organization that assembles
and supplies of SHC to the end user).

• Supply as a basic part of SHC; in this

case the supplier (and also the designer of
equipment family) integrate of those com-
ponents of hardware and software, that are
directly speciied in contract; adaptation for
performance of speciied functions (design
of application software and its integration
with a basic part of SHC) is performed by
the customer.

• Supply as a complete SHC; in this case the

supplier (equipment family designer) him-
self determines components of hardware
and software required for performance of
functions speciied by the end user, de-
velops application software and performs
integration of all component parts and test-
ing of SHC. The end user obtains a fully
debugged and tested “turnkey” SHC.

Some organizations prefer not provide free
access to developed documentation and hardware.