SIRIUS 3RV2 motor starter protectors 
  4.9 Accessories 
SIRIUS Innovations 
System Manual, 01/2011, A8E56203870002-03 
417 
Undervoltage release with leading auxiliary contacts 
The undervoltage release with leading auxiliary contacts has the same function as the 
undervoltage release without auxiliary contacts.  
Additional functions: 
●  The auxiliary contacts ensure that the undervoltage release is only energized during the 
motor starter protector's ON time. 
●  The auxiliary contacts isolate the overvoltage release from the line on both sides when 
the voltage is disconnected or in the event of tripping, thereby preventing vagabond 
voltages from getting into the control circuit when the switch is set to OFF. This requires a 
conductive connection between outputs D2 and 08. 
●  Because the contacts are leading contacts, the power supply to the undervoltage release 
is assured before the remaining steps involved in switching on are carried out. 
4.9.5.2  Auxiliary release voltage ranges 
Table 4- 16  Undervoltage release voltage ranges  
Frequency 
Auxiliary release 
DC  50 Hz AC  60 Hz AC 
24 V  - 
110 V  120 V 
-  208 V 
230 V  240 V 
400 V  440 V 
415 V  480 V 
Undervoltage release  24 V 
500 V  600 V 
230 V  240 V 
400 V  440 V 
Undervoltage release with leading 
auxiliary contacts 
- 
415 V  480 V 
 
Table 4- 17  Shunt release voltage ranges 
Frequency 
Auxiliary release 
50/60 Hz AC 
100% ED 
1)
 
50/60 Hz AC; DC 
5 s ED 
2)
 
20 to 24 V  20 to 70 V 
90 to 110 V  70 to 190 V 
210 to 240 V  190 to 330 V 
350 to 415 V  330 to 500 V 
Shunt release 
500 V  500 V 
1) 
  The voltage range is valid for 100% (infinite) ON period. The response voltage lies at 0.9 of the lower limit of the voltage 
range. 
2)
  The voltage range is valid for 5 s ON period at 50 Hz/60 Hz AC and DC. The response voltage lies at 0.85 of the lower 
limit of the voltage range.