Siemens 7SK80 - Motor Restart Inhibit

Technical Data
4.11 Motor Restart Inhibit
SIPROTEC, 7SK80, Manual
E50417-G1140-C344-A5, Release date 11.2012
386
4.11 Motor Restart Inhibit
Setting Ranges / Increments
Restart Threshold
Tolerances
Influencing variables
Motor starting current relative to nominal motor current
I
Start
/I
Motor Nom.
1.1 to 10.0 Increment 0.1
Nominal motor current
I
Motor Nom.
for I
Nom
= 1 A 0.20 A to 1.20 A Increment 0.01 A
for I
Nom
= 5 A 1.00 A to 6.00 A
Max. permissible starting time T
START max.
1 s to 320 s Increments 1 s
Equilibrium time T
Equal
0.0 min to 320.0 min Increments 0.1 min
Minimum inhibit time T
MIN. INHIBIT TIME
0.2 min to 120.0 min Increments 0.1 min
Maximum permissible number of warm startups n
WARM
1 to 4 Increment 1
Difference between cold and warm startups n
COLD
- n
WARM
1 to 2 Increment 1
Extension of Time Constant at stop k
τ at STOP
0.2 to 100.0 Increment 0.1
Extension of Time constant at running k
τ at RUNNING
0.2 to 100.0 Increment 0.1
Where: Θ
RESTART
= Temperature limit below which restarting is possible
k
R
= k-factor for the rotor
I
STARTUP
= Startup current
I
MotNom
= Motor nominal current
T
start max
= Max. startup time
τ
R
= Thermal rotor time constant
n
cold
= Max. number of cold starts
Restart inhibit time 5 % or 2 s
Trip on rotor overload 5 % or 2 s
Power supply direct voltage in range 0.8 ≤ V
PS
/V
PSNom
≤ 1.15 1 %
Temperature in range –5 °C ≤ Θ
amb
≤ 55 °C 0.5 %/10 K
Frequency in the range from 25 Hz to 70 Hz
Frequency in the range of 0.95 ≤ f/f
Nom
≤ 1.05 (f
Nom
= 50 Hz or 60 Hz) 1 %
Frequency outside range of 0.95 ≤ f/f
Nom
≤ 1.05 Increased tolerances