Basler Electric BE1-700 - Manual (Page 184)

EMBEDDED LOGIC SCHEMES FOR BE1-700C
700C-5051-A-BE (Basic Overcurrent Protection) Logic Scheme
This logic scheme provides basic time and instantaneous overcurrent protection. Phase, neutral, and
negative-sequence protective elements are included. Functions such as virtual breaker control and virtual
switches (43) are not enabled in this scheme but can be activated through BESTlogic. This scheme can
be applied as feeder protection, transformer overcurrent protection, bus overcurrent differential protection,
etc.
700C-OC79-A-BE (Overcurrent Protection with Reclosing) Logic Scheme
This logic scheme provides time overcurrent elements and both high-set and low-set instantaneous
overcurrent elements for phase, neutral and negative-sequence protection for any overcurrent application.
Automatic reclosing is included and is initiated (RI) by a protective trip or by an external reclose initiate
contact. This scheme is ideal for protecting radial distribution feeders that require automatic reclosing
such as with overhead construction.
EMBEDDED LOGIC SCHEMES FOR BE1-700V
700V-OUVF-A-BE (Over/Undervoltage and Voltage Protection) Logic Scheme
This logic scheme provides basic voltage and frequency protection. The scheme is well suited for 3-phase
bus over/undervoltage protection including phase rotation, and underfrequency load shedding.
700V-VF79-A-BE (Voltage Protection with Reclosing) Logic Scheme
This logic scheme provides voltage and frequency protection and includes network reclosing with
separate pilot and time delay reclose initiates. The scheme is well suited for basic distributed generation
protection, 3-phase bus over/undervoltage protection including phase rotation, underfrequency load
shedding with rate of change supervision, and network reclosing applications such as replacement of
Astand-alone@ automatic reclosing, voltage and sync angle detection products.
DETAILS OF PREPROGRAMMED LOGIC SCHEMES
The following paragraphs expand on the individual preprogrammed logic schemes for the BE1-700 series
of products. The application features of each logic scheme are broken down into their separate protection
elements and described in detail. The integration of protection and control elements and alarm elements
are also described in detail. Although it is not discussed in each paragraph, the reader should be aware
that the application of an independent, overlapping, backup zone of protection is recommended for a
complete protection design.
The preprogrammed protection logic scheme begins with the application intent of the design. Next, the
protection elements are discussed, followed by protection and control integration and alarm information
specific to the preprogrammed design. Unique references for the scheme, including one-line and logic
diagrams and program codes are included.
Preprogrammed logic can be a starting point or an ending point for the protection engineer depending on
how closely the logic meets engineering requirements. These logic schemes were created by applications
personnel from the utility industry and are easily modified to meet specific user needs. For applications
assistance, contact your local Basler Electric representative.
700C-5051-A-BE (BASIC OVERCURRENT) LOGIC SCHEME (BE1-700C)
This logic scheme is intended for applications requiring three-phase and neutral non-directional
overcurrent protection. While not as elaborate as the other preprogrammed schemes, this logic scheme
provides an excellent base on which to create a custom scheme for a specific application.
The components of this logic scheme are summarized in Tables 8-1 through 8-4. A diagram of the logic is
shown in Figure 8-1. Figure 8-2 shows a one-line drawing for the Basic Overcurrent logic scheme. Table
8-5 shows the logic settings and equations.
8-2 BE1-700 Application 9376700990 Rev M