ABB Relion Technical Manual page 452

Section 12
Control
446
Bay 1
Disc 189 and 289 closed
WA1 not grounded
WA2 not grounded
WA1 and WA2 interconn
WA1
WA2
189 289
152
989
ANSI05000494 V1 EN
Figure 203: Data exchange between interlocking modules
When invalid data such as intermediate position, loss of a control IED, or input board error
are used as conditions for the interlocking condition in a bay, a release for execution of the
function will not be given.
On the local HMI an override function exists, which can be used to bypass the interlocking
function in cases where not all the data required for the condition is valid.
For all interlocking modules these general rules apply:
• The interlocking conditions for opening or closing of disconnectors and grounding
switches are always identical.
• Grounding switches on the line feeder end, for example, rapid grounding switches,
are normally interlocked only with reference to the conditions in the bay where they
are located, not with reference to switches on the other side of the line. So a line
voltage indication may be included into line interlocking modules. If there is no line
voltage supervision within the bay, then the appropriate inputs must be set to no
voltage, and the operator must consider this when operating.
• Grounding switches can only be operated on isolated sections for example, without
load/voltage. Circuit breaker contacts cannot be used to isolate a section, that is, the
status of the circuit breaker is irrelevant as far as the grounding switch operation is
concerned.
• Disconnectors cannot break power current or connect different voltage systems.
Disconnectors in series with a circuit breaker can only be operated if the circuit
breaker is open, or if the disconnectors operate in parallel with other closed
connections. Other disconnectors can be operated if one side is completely isolated,
Station bus
Bay n
Disc 189 and 289 closed
. . . WA1 not grounded
WA2 not grounded
WA1 and WA2 interconn
. .
189 289
152
989
1MRK 502 048-UUS A
Bus coupler
WA1 ungrounded
WA1 ungrounded
WA1 and WA2 interconn
WA1 and WA2 interconn
in other bay
289 189G
189
152
en05000494_ansi.vsd
Technical manual
289G