GE L30 Instruction Manual page 270

5.6 GROUPED ELEMENTS
usually not critical. This delay will provide security against spurious neutral current during switch-off transients and
external fault clearing.
• CURRENT DIFF DTT: This setting enables and disables the sending of a DTT by the current differential element on
per single-phase basis to remote devices. To allow the L30 to restart from master-master to master-slave mode (very
important on three-terminal applications),
• CURRENT DIFF KEY DTT: This setting selects an additional protection element (besides the current differential ele-
ment; for example, distance element or breaker failure) which keys the DTT on a per three-phase basis.
For the current differential element to function properly, it is imperative that all L30 devices on the pro-
tected line have exactly identical firmware revisions. For example, revision 5.62 in only compatible with
NOTE
5.62, not 5.61 or 5.63.
5
5-126
must be set to "Enabled".
CURR DIFF DTT
L30 Line Current Differential System
5 SETTINGS
GE Multilin