GE MULTILIN 269 MOTOR MANAGEMENT RELAY Series, Инструкция по эксплуатации

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3 SETUP AND USE
3-58
3.24 Statistical Data Features
The model 269 relay offers a record of maximum RTD
temperatures and pre-trip current and RTD values. The
maximum RTD temperature data is found on page 2 of
ACTUAL VALUES mode and can be cleared to zero by
storing a YES in response to the "CLEAR LAST
ACCESS DATA?" question at the end of page 2. Pre-
trip motor current and temperature values are found in
ACTUAL VALUES mode, page 5. These values will be
updated only when a relay trip occurs. Note that if a
trip function setpoint is set to INST. (instantaneous) and
this type of trip occurs, the values for pre-trip current
will not be recorded exactly. This is because the relay
has tripped instantaneously and thus did not have
enough time to update the registers holding this infor-
mation. The pre-trip values can be cleared to zero by
storing a YES in response to the “CLEAR PRE-TRIP
DATA?” question at the end of page 5 of Actual Values.
Running hours and MegaWatt hours can be cleared to
zero by storing a value of YES in response to the
"START NEW COMMISSIONING?" question at the end
of page 4.
The running hours and MegaWatt hours data will reset
to zero after each reaching the number 65535.
If a 269 relay is to be taken out of service for mainte-
nance or testing purposes, the statistical data accu-
mulated by the relay may be copied to the new relay
replacing it. Simply record the information from page 4
of Actual Values and call the factory for a detailed pro-
cedure on transferring this information to the new relay.
The obvious benefit of this exercise is the ability of the
new relay to start with accurate data about the motor
and the system to maintain a continuity from relay to
relay during maintenance or testing of the original 269.
When the original relay is ready to be reinstalled, the
same procedure may be followed to transfer the accu-
mulated statistical data from the replacement relay to
the original 269.
3.25 Factory Setpoints
When the 269 relay is shipped, it will have default set-
points stored in its non-volatile memory. These values
are meant to be used as a starting point for program-
ming the relay and should be changed as each appli-
cation requires.
In the event of a non-volatile memory failure, which will
be detected by the self-test feature (see section 3.23),
the 269 relay will reload the factory setpoints but will
not provide motor protection.
A list of the motor current, RTD, and overload curve
setpoints is given in Table 3-6. For other factory set-
points see Tables 3-7 and 3-3.
3.26 Meter Option
The addition of a GE Multilin MPM meter to a 269 pro-
vides valuable voltage and power measurement. These
values are good for troubleshooting and protective
features.
In order to install the MPM, all connections to the meter
must be made. Then, on the 269 page 7 of Setpoints,
meter CT primary, VT ratio and VT secondary must be
programmed. These setpoints will be sent to the meter
via the communication link for meter calculations.
*** IMPORTANT *** Only after the above steps are
complete may the meter be brought on-line by chang-
ing the meter on-line setpoint (page 7) to YES. The 269
will then initiate communication with the meter and
actual values from the meter may be displayed.
A value for MegaWattHours from 0-65535 may be dis-
played in the Statistical data of Actual Values page 4.
Voltage, KWatts, KVARS, Power Factor, and Frequency
may be viewed on page 7 of Actual Values. These val-
ues may also be seen as their pre-trip levels on page 5
of Actual Values.
The Undervoltage trip and alarm levels determine the
threshold that voltage must fall below for an alarm or
trip condition to exist. The time delay set determines
the amount of time that these conditions must persist
before an actual trip or alarm occurs.
The Power Factor Lag and Power Factor Lead trip and
alarm levels determine the threshold that the power
factor must fall below for an alarm or trip condition to
exist. The time delay set determines the amount of
time that these conditions must persist before an actual
trip or alarm occurs.
Power Factor is commonly used for synchronous motor
protection. Ideally, synchronous motors run at unity
power factor. Conditions may exist where the power
factor drops below an acceptable level. This may be
caused by several factors, such as the loss of field to
the main exciter, accidental tripping of the field breaker,
short circuits in the field currents, poor brush contact in
the exciter, or loss of AC supply to the excitation sys-
tem.