Technical Data
4.4 Thermal Overload Protection (ANSI 49)
SIPROTEC, 7UM62, Manual
C53000-G1176-C149-7, Release date 03.2010
471
4.4 Thermal Overload Protection (ANSI 49)
Setting Ranges / Increments
Tripping Characteristic
Dropout Ratios
Tolerances
Factor k according to IEC 60255-8 0.10 to 4.00 Increments 0.01
Time constant τ 30 s to 32000 s Increments 1 s
Extension of Time Constant at Standstill 1.0 to 10.0 Increments 0.1
Thermal alarm Θ
Alarm
/Θ
Trip
referred to the tripping temperature
70 % to 100 % Increments 1 %
Current Overload I
Alarm
for I
N
= 1 A 0.10 A to 4.00 A Increments 0.01 A
for I
N
= 5 A 0.50 A to 20.00 A Increments 0.01 A
Nominal Overtemperature (for I
N
) 40 °C to 200 °C Increments 1 °C
Coolant Temperature for Scaling 40 °C to 300 °C Increments 1 °C
Limit current I
Limit
for I
N
= 1 A 0.50 A to 8.00 A Increments 0.01 A
for I
N
= 5 A 2.00 A to 40.00 A Increments 0.01 A
Emergency time
T
Emergency Start
10 s to 15000 s Increments 1 s
see also Figure 4-4
Θ/Θ
Off
Dropout with Θ
Alarm
Θ/Θ
Alarm
approx. 0.99
I/I
Warn
approx. 0.95
Referring to k · I
N
for I
N
= 1 A 2 % or 10 mA ; class 2 % acc. to
IEC 60255-8
for I
N
= 5 A 2 % or 50 mA ; class 2 % acc. to
IEC 60255-8
referred to Trip Time 3 % or 1 mA ; class 3 % acc. to
IEC 60255-8 for I/(k ·I
N
) > 1.25