ABB Relion REG670, Technical Manual

Page: 765 / 1298

avoid unnecessary operation during shorter voltage deviations from the target value,
and in order to coordinate with other automatic voltage controllers in the system.
TCMYLTC and TCLYLTC are an interface between TR1ATCC and TR8ATCC and
the transformer load tap changer. More specifically this means that it receives
information from TR1ATCC or TR8ATCC and based on this it gives command-
pulses to a power transformer motor driven on-load tap changer and also receives
information from the load tap changer regarding tap position, progress of given
commands, and so on.
TCMYLTC and TCLYLTC also serve the purpose of giving information about tap
position to the transformer differential protection T2WPDIF and T3WPDIF.
14.4.10 Technical data
Table 447: TCMYLTC and TLCYLTC technical data
Function Range or value Accuracy
Transformer reactance (0.1–200.0)Ω, primary -
Time delay for lower
command when fast step
down mode is activated
(1.0–100.0) s -
Voltage control set voltage (85.0–120.0)% of UBase ± 0.25 % of U
r
Outer voltage deadband (0.2–9.0)% of UBase -
Inner voltage deadband (0.1–9.0)% of UBase -
Upper limit of busbar voltage (80–180)% of UBase ± 0.5% of U
r
Lower limit of busbar voltage (70–120)% of UBase ± 0.5% of U
r
Undervoltage block level (50–120)% of UBase ± 0.5% of U
r
Time delay (long) for
automatic control commands
(3–1000) s ± 0.2% or ± 600 ms
whichever is greater
Time delay (short) for
automatic control commands
(1–1000) s ± 0.2% or ± 600 ms
whichever is greater
Minimum operating time in
inverse mode
(3–120) s ± 0.2% or ± 600 ms
whichever is greater
Line resistance (0.00–150.00)Ω, primary -
Line reactance (-150.00–150.00)Ω, primary -
Load voltage adjustment
constants
(-20.0–20.0)% of UBase -
Load voltage auto correction (-20.0–20.0)% of UBase -
Duration time for the reverse
action block signal
(30–6000) s ± 0.2% or ± 600 ms
whichever is greater
Current limit for reverse
action block
(0–100)% of I1Base -
Overcurrent block level (5–250)% of I1Base ± 1.0% of I
r
at I≤I
r
± 1.0% of I at I>I
r
Level for number of counted
raise/lower within one hour
(0–30) operations/hour -
Table continues on next page
1MRK502052-UEN B
Section 14
Control
759
Technical manual