Functions
2.4 Backup Overcurrent
SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011
91
Time Delays
The time delays are set specifically for each element:
50-B2 DELAY
,
67-B2 DELAY
addess
2624
50N-B2 DELAY
,
67N-B2 DELAY
addess
2627
50-B1 DELAY
,
67-B1 DELAY
addess
2614
50N-B1 DELAY
,
67N-B1 DELAY
addess
2617
51-B TD IEC
,
67-TOC TD IEC
addess
2634
(IEC characteristic)
51N-B TD IEC
,
67N-TOC TD IEC
addess
2639
(IEC characteristic)
51-B TD ANSI
,
67-TOC TD ANSI
addess
2635
(ANSI characteristic)
51N-B TD ANSI
,
67N-TOC TD ANSI
addess
2640
(ANSI characteristic)
They are determined by the time grading chart created for the power system. If used as emergency overcurrent
protection, shorter tripping times are advisable as this function is only activated in the case of the loss of the
local measuring voltage.
The times for the ground current elements can be set shorter, according to a separate time grading chart for
ground currents.
You can set additional time delays for definite-time elements with IEC characteristic.
51-B AddT-DELAY
,
67-TOC AddTDel.
addess
2636
51N-B AddTdelay
,
67N-TOC AddTDel
addess
2641
Instantaneous Tripping via Binary Input
Binary input
„>5X-B InstTRIP“
allows you to bypass the time delays. The binary input applies to all ele-
ments collectively.
You can specify for each element whether instantaneous tripping takes effect. The setting applies collectively
to the corresponding phase and ground element.
50-1
, 3I0>
address
2628
50-2
, 3I0>>
address
2618
50N
, 3I0p
address
2644
The following settings are possible:
• If set to
YES
, the element trips instantaneously when the binary input is activated.
• When set to
NO
, the set time delays take effect.