Siemens siprotec 7SJ63, Инструкция по эксплуатации

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Functions
6-104
7SJ63 Manual
C53000-G1140-C120-1
culated operating temperature falls below the warning level, thus allowing the protect-
ed equipment to be placed back into service.
The thermal warning level is given in % of the tripping temperature level (maximum
allowable operating temperature).
A current warning level is also available (
,$/$50
). The setting at address
corresponds to secondary amperes, of course, and should be set equal to, or slightly
less than, permissible continuous current (k * I
Nsec)
. The current warning level may be
used in lieu of the thermal warning level by setting the thermal warning level to 100 %.
Extension of Time
Constants The time constant programmed at address 4203 is valid for a running motor. For cy-
cling motors without external cooling, the motor loses heat more slowly. For a cycling
motor, the 7SJ63 takes the reduced heat loss into account by increasing the time con-
stant
τ
by a programmable factor k
τ
(set at address ). If no distinguishing of the
time constants is necessary (e.g. externally-cooled motors, cables, transformers, etc.)
the
.
τ
)$&725
is set at (Default Setting value).
Emergency Starting The drop-out time to be entered at address 4208 must be sufficient to allow the calcu-
lated operating temperature to decrease below the drop out level.
Motor Starting Rec-
ognition To ascertain whether or not a motor is starting, the motor currents are compared with
the setting at address
. If the motor currents exceed the setting at address ,
a motor starting condition is assumed. Information on how to set address is giv-
en in Subsections 6.1.3 and 6.8.2.
6.9.2.1 Settings for Thermal Overload Protection
In the list below, the setting range and default setting value for I ALARM is for a device
with a nominal current rating I
N
= 5 A. For a nominal current rating I
N
= 1 A, divide the
Setting Options values and Default Setting value by 5. Consider the current transform-
er ratios when setting the device with primary values.
Addr. LCD-Text Setting options Default Setting Comment
4201 FCT 49 OFF
ON
Alarm only OFF 49 Thermal overload protection
4202 49 K-FACTOR 0.10 ~ 4.00 1.10 49 (Service Factor k)
4203 TIME CONSTANT 1.0 ~ 999.9 min 100.0 min Time Constant
4204 49
Θ
ALARM 50 ~ 100% 90% 49 Thermal warning stage
4205 I ALARM 0.50 ~ 20.00 A 5.00 A Current warning stage
4207 K
τ
-FACTOR when
motor stops
1.0 ~ 10.0 1.0 K
τ
time factor for non-running
motor
4208
T EMERGENCY
10 ~ 15000 sec 100 sec Dropout time after emergency
start-up
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