voltage sequence measurement functions (CMSQI and
VMSQI) and IEC 61850 generic communication I/O
functions (MVGAPC) are provided with measurement
supervision functionality. All measured values can be
supervised with four settable limits: low-low limit, low
limit, high limit and high-high limit. The measure value
expander block (RANGE_XP) has been introduced to
enable translating the integer output signal from the
measuring functions to 5 binary signals: below low-low
limit, below low limit, normal, above high limit or above
high-high limit. The output signals can be used as
conditions in the configurable logic or for alarming
purpose.
Insulation supervision for gas medium function
SSIMG
GUID-0692CD0D-F33E-4370-AC91-B216CAAAFC28 v7
Insulation supervision for gas medium (SSIMG) is used
for monitoring the circuit breaker condition. Binary
information based on the gas pressure in the circuit
breaker can be used as input to the function. In addition,
the function can be used with an analog value of gas
pressure and temperature of the insulation medium and
binary inputs. The function generates alarms based on
received information.
Insulation supervision for liquid medium SSIML
GUID-3B1A665F-60A5-4343-85F4-AD9C066CBE8D v8
Insulation supervision for liquid medium (SSIML) is used
for monitoring the oil insulated device condition. For
example, transformers, shunt reactors, and so on. Binary
information based on the liquid level in the circuit
breaker can be used as input to the function. In addition,
the function can be used with an analog value of liquid
level and temperature of the insulation medium and
binary inputs. The function generates alarms based on
the received information.
Circuit breaker condition monitoring SSCBR
GUID-E1FD74C3-B9B6-4E11-AA1B-7E7F822FB4DD v14
The circuit breaker condition monitoring function
(SSCBR) is used to monitor different parameters of the
breaker condition. The breaker requires maintenance
when the number of operations reaches a predefined
value. For a proper functioning of the circuit breaker, it
is essential to monitor the circuit breaker operation,
spring charge indication or breaker wear, travel time,
number of operation cycles and estimate the
accumulated energy during arcing periods. Each SCCBR
function instance is made to be used with a 1-pole, 1-
phase breaker.
Event counter with limit supervison L4UFCNT
GUID-13157EAB-1686-4D2E-85DF-EC89768F3572 v6
The Limit counter (L4UFCNT) provides a settable
counter with four independent limits where the number
of positive and/or negative flanks on the input signal
are counted against the setting values for limits. The
output for each limit is activated when the counted
value reaches that limit.
Overflow indication is included for each up-counter.
Running hour-meter TEILGAPC
GUID-464FB24F-B367-446C-963A-A14841943B87 v2
The Running hour-meter (TEILGAPC) function is a
function that accumulates the elapsed time when a
given binary signal has been high.
The main features of TEILGAPC are:
• Applicable to very long time accumulation (≤ 99999.9
hours)
• Supervision of limit transgression conditions and
rollover/overflow
• Possibility to define a warning and alarm with the
resolution of 0.1 hours
• Retain any saved accumulation value at a restart
• Possibilities for blocking and reset
• Possibility for manual addition of accumulated time
• Reporting of the accumulated time
Estimation of transformer winding insulation life
LOLSPTR
GUID-CDE89397-8E99-4873-9701-FF642101A308 v2
Estimation of transformer winding insulation life
(LOLSPTR) is used to calculate transformer winding hot
spot temperature using the empirical formulae. It is also
used to estimate transformer loss of life from the
winding hot spot temperature value. The transformer
winding insulation is degraded when the winding hot
spot temperature exceeds certain limit. LOLSPTR gives
warning and alarm signals when the winding hot spot
temperature reaches a set value.
Hot spot temperature calculation requires top oil
temperature at a given time. This value can either be a
measured value taken through sensors or the one
calculated by the function. This decision is made based
on the top oil temperature sensor quality. Top oil
temperature calculation is done using the method
explained in IEC 60076-7 standard.
Inputs required for hot spot temperature calculation
are:
• Transformer oil time constant
• Winding time constant
• Loss ratio at different tap positions
• Ambient temperature around the transformer
The oil and winding time constants can be calculated by
the function based on transformer parameters if the
inputs are not available from the transformer
manufacturer.
Ambient temperature to the function can either be
provided through the sensor or monthly average
ambient temperature settings. This decision is made
based on the ambient temperature sensor quality.
Additionally, LOLSPTR function provides difference
Generator protection REG670
1MRK 502 074-BEN M
Hitachi Power Grids 43
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