Siemens SINAMICS PERFECT HARMONY GH180 Function Manual page 70

Advanced Motor Protection and RTD Protection Functions
6.15 Device 49T - Machine Thermal Model - Variable Parameter Thermal Overload
Keypad Parameter Text
Tool Parameter Help Text
90% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
90% Speed Demand
100% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
100% Speed Demand
110% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
110% Speed Demand
120% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
120% Speed Demand
130% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
130% Speed Demand
140% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
140% Speed Demand
150% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
150% Speed Demand
160% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
160% Speed Demand
170% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
170% Speed Demand
180% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
180% Speed Demand
190% Speed k-Factor
Define Ratio of Max I to Infinite time trip I in Seconds at
190% Speed Demand
The k-Factor can be varied as a function of the demand to effectively change the value of
current at which the steady state value of the thermal capacity used is equal to 100%. Since
losses increase with increasing frequency, the current required to reach rated machine
temperature is likely to be lower at high speeds. A reduced k factor at higher demand settings
can be used to adjust the steady state value of thermal capacity used to account for such speed
effects. Adjustment of the k factor as a function of the speed demand can also be used to
account for decreased cooling effects at low speeds in cases where the cooling is diminished
at low speeds. Figure " Use of a Variable k-Factor in Variable Thermal Overload Protection
Function" shows an example of how to use the 20 parameters to define a k-Factor variation with
the demand setting. The values of the parameters are given in Table "Values of the k-Factor
Settings". Note that the programmed value at 190% demand is used at all speeds in excess of
190%.
68
ID Units Default
Value
7408
7409
7410
7411
7412
7413
7414
7415
7416
7417
7418
Advanced Motor Protection for Variable Speed Operation
Minimum - Maximum Value
1.15 0 - 1.5
1.1 0 - 1.5
1.06 0 - 1.5
1.02 0 - 1.5
0.99 0 - 1.5
0.95 0 - 1.5
0.91 0 - 1.5
0.87 0 - 1.5
0.83 0 - 1.5
0.79 0 - 1.5
0.75 0 - 1.5
Manual, AA, A5E46373908A