Siemens SIRIUS 3RU - Page 77

Configuration
6.6 Application environment
SIRIUS 3RU thermal overload relays / SIRIUS 3RB electronic overload relays
Manual, 09/2016, A5E03656507420A/RS-AB/003
77
Ambient temperatures for 3RU21 overload relays
3RU21 thermal overload relays compensate temperature in the temperature range from –
40 °C to +60 °C according to IEC/EN 60947-4-1. At temperatures between
+60 °C and +70 °C, the maximum permissible operating current related to the rated
operating current must be reduced by a specific factor f in accordance with the table below
(I
max
= I
e
x f).
Table 6- 7 Ambient temperatures for 3RU21 overload relays (size S00/S0)
Ambient temperature in °C
Reduction factor applies for rated current ...
0.16 ... 20 A
22 ... 40 A
+60
1.0
1.0
+65
0.94
0.97
+70 0.87 0.94
Table 6- 8 Ambient temperatures for 3RU2136 overload relays (size S2)
Ambient temperature in °C
Reduction factor applies for rated current ...
8 ... 45 A
50 ... 80 A
+60 1.0 1.0
+65
0.94
0.97
+70
0.87
0.94
Table 6- 9 Ambient temperatures for 3RU2146 overload relays (size S3)
Ambient temperature in °C
Reduction factor applies for rated current ...
25 ... 32 A
40 ... 63 A
75 ... 100 A
+60
1.0
1.0
1.0
+65
0.94
0.95
0.97
+70
0.88
0.90
0.94