Sel SEL-787 - Table 6.6 Setting Interdependency Error Messages

6.6
SEL-787 Relay Instruction Manual Date Code 20150130
Settings
Setting Entry Error Messages
Setting Entry Error Messages
As you enter relay settings, the relay checks the setting entered against the
range for the setting as published on the relay setting sheet. If any setting
entered falls outside the corresponding range for that setting, the relay
immediately responds
Out of Range and prompts you to reenter the setting.
In addition to the immediate range check, several of the settings have
interdependency checks with other settings. The relay checks setting
interdependencies after you answer
Y to the Saves Settings? prompt, but
before the settings are stored. If any of these checks fail, the relay issues a
self-explanatory error message, and returns you to the settings list for a
correction. Table 6.6 shows the settings interdependency error messages that
require some additional explanation and guidance.
Table 6.6 Setting Interdependency Error Messages
Error Message Setting/Function Correct the Condition
Tap(s) out of range,
enter values manually
a
Group settings, differential element
autocalculation of TAP1 and TAP2
Check:
0.1 • INOMn < TAPn < 6.2 • INOMn. (INOMn = 5 or 1
for 5 A and 1 A winding CT based on PARTNO). Should
either TAPn value violate this requirement, adjust the
affected TAPn to satisfy the check (n = 1 or 2).
Maximum-to-minimum
TAP ratio must be 7.5
a
Group settings, differential element
autocalculation of TAP1 and TAP2
Check:
[MAX (TAP1/INOM1, TAP2/INOM2)/MIN(TAP1/
INOM1, TAP2/INOM2)]  7.5.
Adjust TAP1 or TAP2 setting until the check is satisfied.
WnCT, REF1POL
Setting Combination
Invalid n =1or 2
Group settings, REF element REF Element is only available when setting WnCT := WYE
(n =1 or 2).
a
Relay forces MVA := OFF prior to this message.