Braking Resistors 03.2004
6SE7087-7CX87-2DA0 Siemens AG
4-2 Unité de Freinage / Braking Unit SIMOVERT MASTERDRIVES
4.1 Definitions of the power ratings
Braking unit with external resistor Braking unit with internal resistor
P20 = Rated Power P20 = Rated Power
P3 = Peak Power = 1.5
× P20 P3 = Peak Power = 1.5 × P20
PDB = 0.25
× P20 = Steady State Power Rating PDB = 0.03 × P20 = Steady State Power Rating
P
t[s]
0 3 20
23
90
0
P3
P20
PDB
1.5
1
0.25
P
t[s]
1.7 2.5
72.5
0
0
P3
P20
PDB
1.5
1
0.03
Fig. 4-1 Load characteristics of the braking units