3 SETUP AND USE
3-50
JAM TIME DELAY” setpoints will then be disregarded
by the relay.
Note: These features are not recommended for use
with systems that experience overloads as part of
normal operation.
3.14 Short Circuit Setpoints
The Short Circuit protective function provides overriding
protection for any large phase current. Complete pro-
tection from phase-to-phase and phase-to-ground
faults is provided with this feature. This feature is ac-
tive at all times, including during motor starts, unless
the "SHORT CIRCUIT TRIP LEVEL" is set to OFF. The
setpoints are in SETPOINTS mode, page 1.
The phase current short circuit trip level can be set
from 4 to 12 times motor full load current. The trip can
be instantaneous or can be delayed by up to 20.5 sec-
onds to facilitate coordination with system switchgear.
If this feature is not desired the "SHORT CIRCUIT TRIP
LEVEL" setpoint should be set to "OFF". If this is done
the relay will disregard the "SHORT CIRCUIT TIME
DELAY" setpoint.
CAUTION! When using this feature be certain that
the interrupting device can safely open to break the
short circuit duty. Otherwise this setpoint must be
set to OFF. Other means of interrupting fault cur-
rents must then be used (e.g. fuses).
3.15 Immediate Overload Alarm Level
Setpoint
The Immediate Overload Alarm Level setpoint is found
in SETPOINTS mode, page 1. It is adjustable from
1.01 XFLC to 1.50 XFLC. An output relay activation
will occur immediately when the average phase current
goes over the setpoint value. This function can never
cause latched (manual reset) relay operation.
An Immediate Overload Alarm will not be issued when
the motor is started. This function is only active when
the motor is in the run mode.
3.16 Stator RTD Setpoints
The 269 is ordered with one of the following RTD types:
100 ohm platinum, 10 ohm copper, 100 ohm nickel, or
120 ohm nickel. A message on page 2 of Setpoints
may be examined to determine the type of RTD built
into the relay.
It is possible to operate the 269 without connecting any
RTDs to it. A setpoint on page 2 of Setpoints asks the
question:
ARE THERE ANY RTDsARE THERE ANY RTDs
CONNECTED? NOCONNECTED? NO
if the answer is “NO”, the 269 hides all RTD related
Setpoints and Actual Values thus making it easier to
program for the application.
The 269 relay displays temperatures in either Celsius
or Fahrenheit depending on the RTD Message Display
setpoint. If Fahrenheit option is chosen the increment
can vary between 1 and 2 due to the conversion from
Celsius to Fahrenheit and the rounding of the result.
NOTE: CARE MUST BE TAKEN NOT TO ENTER
CELSIUS VALUES FOR SETPOINT PARAMETERS
WHEN IN FAHRENHEIT MODE AND VICE-VERSA.
The 269 relay has 6 sets of 4 terminals available for the
connection of RTDs to monitor the temperature of the
stator windings. If fewer than 6 RTDs are to be used
they must be connected to the lowest numbered RTD
connections on the rear of the relay. The stator RTD
setpoints are found in SETPOINTS mode, page 2. The
"# OF STATOR RTDS USED" setpoint should be cho-
sen to represent the number of RTDs actually con-
nected to the motor stator windings. Thus if 3 RTDs
are connected to the stator, the "# OF STATOR RTDS
USED" setpoint should be set to 3, and the 3 RTDs
must be connected to the terminals for RTD1, RTD2,
and RTD3 (terminals #1-12).
There are individual trip and alarm setpoints for each
RTD. A relay activation will occur when any one of the
RTD temperatures goes over its corresponding setpoint
value. The maximum stator RTD temperature at any
time will be used for relay thermal calculations. Activa-
tion will occur when at least two stator RTDs go over
their corresponding setpoints. This is the case when the
“Stator RTD Voting” scheme is in effect. Other RTDs
are not affected by the voting feature. Trip relay activa-
tion for other RTDs will occur when any one of the RTD
temperatures goes over its setpoint value. This is also
the case for stator RTDs if voting is defeated. Stator
RTD alarms, high alarms and other RTD Alarms are
also issued based on individual RTD setpoints. The
maximum stator RTD temperature at any time will be
used for relay thermal calculation.
When the relay is in ACTUAL VALUES mode the tem-
perature readings from all of the RTDs may be dis-
played. If no connection has been made to any RTD
terminals, the display for that RTD will be "no RTD". If
the answer to the question “ARE THERE ANY RTDs
CONNECTED?” is “NO”, the display will show “NO
RTDs ARE CONNECTED TO THE 269PLUS”. If the "#
OF STATOR RTDS USED" setpoint is stored as 3, only
the maximum temperature from RTD1, RTD2, and
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