SIRIUS 3RV2 motor starter protectors 
  4.5 Configuration 
SIRIUS Innovations 
System Manual, 01/2011, A8E56203870002-03 
397 
Operating conditions 
3RV2 motor starter protectors are climate-proof. They are intended for use in enclosed 
spaces in which no severe operating conditions prevail (e.g. dust, caustic vapors, hazardous 
gases). If they are to be installed in dusty and damp spaces, suitable enclosures must be 
provided.  
3RV2 motor starter protectors can be supplied from above or below. 
Ambient temperatures/Derating 
The permissible ambient temperatures, maximum switching capacity, tripping currents, and 
other limiting conditions relevant to application are listed in the technical data. Technical 
information is available on the Internet 
(http://www.siemens.com/automation/service&support
). 
3RV2 motor starter protectors are temperature-compensating according to IEC 60947-4-
1/VDE 0660 Part 102 in the temperature range from –20 °C to +60 °C. At temperatures from 
+60 °C to +80 °C, the upper set value of the setting range has to be reduced by a specific 
factor in accordance with the table below. 
Table 4- 5  Ambient temperatures for 3RV2 motor starter protectors 
Reduction factor for the upper set value 
Ambient temperature in °C 
Current ranges 
0.11 to 20 A 
Current ranges 
17 to 32 A 
+60  1.0  1.0 
+65  0.87  0.97 
+70  0.94  0.94 
+75  0.81  0.90 
+80  0.73  0.86 
In accordance with the table, the reduction factor is 13% at 70 °C. This factor is so low that 
due to the overlapping of the current setting ranges there are no gaps before the next setting 
range. This means that at 70 °C the available current range goes from 0.11 A to 32 A.  
 
 
Note 
Ambient temperatures > 40 A 
The 36 A and 40 A versions are compatible for use in ambient temperatures of up to 40° C 
maximum. 
 
Special application environments 
SIRIUS components have been approved by a whole range of bodies for various sectors 
(shipbuilding, etc.). An up-to-date list of approvals appears in Chapter 20 of the Siemens 
Low Voltage LV1 Catalog, and more information, as well as an option to download 
certificates, can be obtained on the Internet 
(http://www.siemens.com/automation/service&support
).