Thytronic DMC3S, Руководство пользователя

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78
DMC3S - Manual - 08 - 2021
— Breaker monitoring
Preface
A variety of diagnostic, measurement and control functions are provided:
• The relay determines the position of the breaker by monitoring the status of auxiliary contacts 52a
and 52b. This information enables the user to issue the open/close commands in complete safety.
• An approximate threshold for the wear of the breaker's poles can be set; when the sum of the in-
terrupted currents ( S I or S I
2
) or the number of opening commands violates this threshold, an alarm
signal is issued. This function enables the user to schedule maintenance.
• The relay determines the opening time by monitoring the status of auxiliary contacts 52a and 52b; if
it is too high, an alarm signal is issued.
Operating logic
By convention, the status of auxiliary contact 52a corresponds to the position of the breaker (52a
open = breaker open), while that of 52b is opposite to the position of the breaker (52b open = breaker
closed); the two auxiliary contacts must be mapped to two logical inputs.
To do so, the functions
52a
and
52b
must be configured in the menu Set \ Input board inputs \ Input
IN1-1...(Input IN1-6) .
The said logical inputs must be programmed with Direct logic and the activation/deactivation timers
IN1 tON
,
INx tON
,
IN1 tOFF
and
INx tOFF
must be zeroed and set to
DIRECT
operating
logic.
BREAKER CONTROL
Two output relays can be programmed to open and close the breaker; to do so, set the parameters
CBopen-K
and
CBclose-K
in the menu Set \ Breaker monitoring \ Associated relays-LEDs ; the
position of the breaker can be displayed by assigning the status to two LEDs (parameters
CBopen-L
and
CBclosed-L
).
All parameters are common to the two calibration configurations.
OPENING COMMAND BREAKER DIAGNOSTICS
The breaker diagnostic function uses a variety of criteria to estimate the wear of the breaker.
1) Opening command count (
ModeN.Open ON
). When the set threshold is violated (
N.Open
) an
alarm signal is issued, which can be assigned to a final relay and/or indicator LED.
2) Opening load command count (
ModeN.MnvLoad ON
). When the set threshold is violated
(
N.MnvLoad
) an alarm signal is issued, which can be assigned to a final relay and/or indicator
LED.
3) Opening no load command count (
ModeN.MnvNoLoad ON
). When the set threshold is vio-
lated (
N.MnvNoLoad
) an alarm signal is issued, which can be assigned to a final relay and/or
indicator LED.
4) Sum of interrupted currents at each pole (
ModeSumI ON
). When the set threshold is violated
(
SumI
) an alarm signal is issued, which can be assigned to a final relay and/or indicator LED..
5) I
2
t sum of interrupted currents at each pole (
ModeSumI ON
). The protection calculates the sum
of the specific pass-through energy I
2
t on the basis of the measurement of the phase currents at
the time of the open command, and using the user programmable breaker opening time specifical-
ly provided for calculating I
2
t (
tbreak
). When the set threshold is violated (
SumI^2t
) an alarm
signal is issued, which can be assigned to a final relay and/or indicator LED..
6) Duration of open command (
Mode-tOpen ON
). The protection measures the time between
the trip command of a protection function, selected in relation to the associated final relay
(
Ktrig-break
), and acquisition of the breaker open status. When the set time period is exceeded
(
tbreak>
) an alarm signal is issued, which can be assigned to a final relay and/or indicator LED..
Fun-CB-position.ai
Towards CB diagnostic
TR
IP
PI
NG M
AT
RI
X
(LE
D)
52a ON/OFF
t
break
0 T
t
break
CB monitoring
Opening transition
52b ON/OFF
52a
52
52b
+ U
AUX
- U
AUX
52a
52b
Binary input INx
T 0
INx t
ON
T 0
n.o.
n.c.
INx tON Logic INx tOF F
INx t
OFF
Binary input INx
T 0
INx t
ON
T 0
n.o.
n.c.
INx tON Logic INx tOF F
INx t
OFF
=1
Functional diagram of the breaker position monitoring function