ABB Distribution Protection Unit 1500R
6-6
Programmable Input and Output Contacts
9/99
website:www.abb.com/papd
Programmable Outputs
All logical outputs except “ALARM” are a logical 0 when the DPU1500R is in a “the normal” state.
Logical Output Types
The programmable logical outputs (or sometimes called alarms) as listed below can have two different types of outputs
for the same function. The first type is a non-sealed-in type. This type of logical output will be a logical 1 (logical output
asserted) when the condition is present and a logical 0 (logical output de-asserted) when the condition ceases. It is
sometimes referred to as a “real time” output. The second type is a sealed-in type. This type of logical output will be a
logical 1 (logical output asserted) when the condition is present and will remain a logical 1 when the condition ceases.
The Sealed-In Outputs are reset by any of the following methods:
1.
The front panel MMI “C” (clear) button is depressed once within a 5-second period. The user will eventually
be prompted to reset seal-ins. See Section 5 for details.
2.
The Sealed In Alarms cam be reset with WinECP by selecting the Control - Resets Menu, and choosing the
Sealed In Alarms command. The Sealed In Alarms can be reset individually, or all at once. See Section 8 for
more details.
3.
Depending on the communications protocol
contained in the DPU1500R, a command is
issued to reset the individual seal-in outputs or
all seal-in outputs.
An example of where seal-in bits are applied: The
DPU1500R is connected directly onto a Modbus
communications network and a Programmable Logic
Controller (PLC) is also on the network. The PLC obtains
fault information from the DPU1500R over the Modbus network for certain restoration scheme. If the fault bit, 51P (3I>) for
example, sensed by the PLC was a real time bit, the PLC would never see the change. The seal-in bit, 51P* (3I>*) can
be used to alert the PLC to a fault even after the fault has extinguished. Once the PLC is finished with the logical output
bit 51P* (3I>*), it can reset the bit to a logical 0 via the communication network. This eliminates hard contact wiring
between the relay and the PLC and assure that the PLC will always see a fault.
Some of the alarms listed below will have duplicate elements. For example, 50P-1 (3I>>1) and 50P-1* (3I>>1*). Notice
that an asterisk (*) follows one of the elements. This is the indication of a logical output that is of the seal-in type as
described above.
Table 6-2: Logical Output Definitions
——:
Entry not used.
TRIP:
Breaker Trip Output. This output follows the action of the physical output contact “Trip”. It is
activated by all of the overcurrent protective elements that are enabled. TRIP is also activated
by the logical input OPEN and operates when the relay is asked to perform a manual circuit
breaker trip by either the front panel MMI or remote WinECP program. See Section 1 under
“Master Trip Contact Dropout” for details on dropout operation of this logical output.
CLOSE:
Breaker Close Output. This output is used by the DPU1500R recloser as the breaker close
output. It must be assigned to the physical output that is connected to the circuit breaker
close coil. CLOSE is also activated by the logical input CLOSE and operates when the relay
is asked to perform a manual circuit breaker close by either the front panel MMI or remote
WinECP program. The CLOSE logical output will become a logical 1 when when the DPU1500R
issues a CLOSE command. CLOSE will remain a logical 1 until the Close Fail Timer expires or
the 52A and 52B contacts indictate that a circuit breaker close state exists.
ALARM:
Self Check Alarm. This output is normally a logical 1, and indicates that the DPU1500R is
functioning normally. When the output is a logical 0, the DPU1500R has failed. This output is
also linked to the physical “Self Check Alarm” contact and the red front panel “Fail” target.
Abbreviation
Description
