Set 
Unblock
= 
Off
(Set to 
NoRestart
 if Unblocking scheme with no alarm for loss of guard is to be
used.
Set to 
Restart
 if Unblocking scheme with alarm for loss of guard is to be used)
Set 
tSecurity
= 0.035 s
Set 
DeltaI
= 10 %IB
Set 
DeltaU
= 5 %UB
Set 
Delta3I0
= 10 %IB
Set 
Delta3U0
= 5 %UB
13.1.3.3  Permissive underreaching scheme
M13869-25 v4
Set 
Operation
= 
On
Set 
SchemeType
= 
Permissive UR
Set 
tCoord
= 0 ms
Set 
tSendMin
= 0.1 s
Set 
Unblock
= 
Off
Set 
tSecurity
= 0.035 s
13.1.3.4  Permissive overreaching scheme
M13869-34 v4
Set 
Operation
= 
On
Set 
Scheme type
= 
Permissive OR
Set 
tCoord
= 0 ms
Set 
tSendMin
= 0.1 s (0 s in parallel line applications)
Set 
Unblock
= 
Off
Set 
tSecurity
= 0.035 s
13.1.3.5  Unblocking scheme
M13869-43 v4
Set 
Unblock
= 
Restart
(Loss of guard signal will give both trip and alarm
Choose 
NoRestart
 if only trip is required)
Set 
tSecurity
= 0.035 s
13.1.3.6  Intertrip scheme
M13869-62 v5
Set 
Operation
= 
On
Set 
SchemeType
= 
Intertrip
Set 
tCoord
= 50 ms (10 ms + maximal transmission time)
Table continues on next page
Section 13 1MRK 505 393-UEN B
Scheme communication
284 Line differential protection RED650 2.2 IEC
Application manual