WEG SRW 01, User Manual

Page: 92 / 148

Parameterization
5-46 | SRW 01
5
The estimated motor temperature is stored in form of voltage on an RC circuit throughout the motor monitoring.
Therefore, by turning off the SRW 01 the motor temperature is kept on the RC circuit, which in its turn simulates
the motor cooling process. When the SRW 01 is energized again, the thermal image is updated from the RC circuit
voltage, provided that P642 = 0.
The Figure 5.23 on page 5-46 presents all the tripping class curves considering service factors (S.F.) of 1.00 and
1.15.
Class 45
Class 40
Class 35
Class 30
Class 25
Class 20
Class 15
Class 10
Class 5
Current
x In
F.S.=1.00
F.S.=1.15
1
10
100
1000
Time
t(s)
1x
2x
3x 4x 5x
6x
7x
8x
9x
10x
9x 8x 7x 6x 5x 4x 3x 2x
1x
Figure 5.23: Tripping classes for cold motor protection