ABB Distribution Protection Unit 1500R
1-4
Protective Functions
9/99
website:www.abb.com/papd
Phase Instantaneous Overcurrent
Element 50P-2 (3I>>2) - Level 2, Mid
set
The 50P-2 function operates when the level
of any phase current exceeds the pickup
level. 50P-2 is used to establish an additional
layer of instantaneous overcurrent protection.
The pickup level of 50P-2 is set as a multiple of the 51P pickup. The timing of the 50P-2 is set strictly as definite time
(see Table 1-4). The 50P-2 pickup is often set higher than the 50P-1 and used to trip faster than the 50P-1 or for
recloser Lockout. See “Reclosing” later in this section. The 50P-2 pickup and time delay are all set in the Primary,
Alternate 1, and Alternate 2 settings groups. For the 50P-2 element to operate the “Trip” contact, it must be selected in
the “Master Trip Output” mapping (see “Programmable Master Trip Contact” later in this section). 50P-2 is set by factory
default to operate the “Trip” contact.
50P-2 tripping can be enabled or disabled in each step of the reclose sequence. See the “Reclosing” Section for more
details. It can also be supervised (torque controlled) by mapping the “PH3” logical input to a physical input for external
supervision or Logical Output for internal supervision. See the “Logical Inputs” Section for programming instructions.
When the two phase 50P tripping function is selected, the 50P-2 element trips only when two or three phases exceed
the pickup setting and does not operate for single phase faults. See also “Two Phase 50P Tripping” later in this section.
50P-1 Parameter
Range/Curve
Time Dial
Increment
Pickup
0.5 to 20 x 51P setting
- - -
0.1x
Instantaneous Curves
Standard
No Delay
- - -
Inverse Instantaneous
1 to 10
0.1
Short Time Inverse
1 to 10
0.1
Short Time Ext. Inverse
1 to 10
0.1
Definite Time
0 to 9.99
0.01
See Table 5-1 for the 50P-1 factory default settings.
Table 1-3. 50P-1 (3I>>1) Characteristics
50P-2 Parameter
Range/Curve
Increment
Pickup
0.5 to 20 x 51P setting
0.1x
Definite Time
0 to 9.99 seconds
0.01 sec.
The 50P-2 element is disabled in the factory default settings.
Table 1-4. 50P-2 (3I>>2) Characteristics
The 50P-1 element tripping can be
enabled or disabled in each step
of the reclose sequence. See
“Reclosing” later in this section for
more details. It can also be
supervised (torque controlled) by
mapping the “PH3” logical input to
a physical input for external
supervision or Logical Output for
internal supervision. See the
“Programmable I/O” Section for
programming instructions. When
the two phase 50P tripping function
is selected, the 50P-1 element
trips only when two or three phases
exceed the pickup setting and does
not operate for single phase faults.
This is applicable where
instantaneous tripping for single phase to ground faults is not desired (see “Two Phase 50P Tripping” later in this
section).
When the circuit breaker is closed by an external source such as a control switch or SCADA, the 50P-1 can be disabled
from tripping for a “Cold Load Time”. See the “Cold Load Time” Section for more details.
Two Phase 50P (3I>>) Tripping
The Two Phase 50P tripping is used to increase sensitivity and improve clearing time for three phase, phase to phase,
and two phase to ground faults on the main section of radial distribution lines. The two phase 50P tripping mode is not
sensitive to single phase to ground faults. When the two phase 50P mode is enabled in the Primary, Alternate 1, or
Alternate 2 settings groups, the 50P-1, 50P-2, and 50P-3 elements will trip only for two or three phase faults. The 50N-
1, 50N-2, and 50N-3 ground instantaneous overcurrent elements will still operate for single phase to ground faults
where the ground current exceeds the 50N-1, 50N-2, and 50N-3 pickup settings. Two Phase 50P tripping is disabled in
the factory default settings. Refer to Application Note AN-24
.
