13 Technical Specifications  
 
 
 
Operating time  IDMT characteristic shape   As per clause 5.2 of IEC60255-
50 ms whichever is greater      
DT operation   ± 5% or 55 ms whichever is greater** 
** Reference condition  Currents applied at 2x pick-up level or  
higher 
CB Fail 
I.   
Operating time  DT operation   ± 5% or 55 ms whichever is greater 
   
CBF Reset   <40 ms* 
   
Reset current  Setting ± 10% 
* Note :  Filtering time (typically 25ms) is added when CBF initiated by external Binary input 
Note:  As per IEC60255-151 clause 5.2 (assigned error 5%), the tolerances are calculated as below. 
Value of characteristic quantity as multiple of setting value (Gs) 
Limiting error as multiple of an assigned error  2.5  1.5  1 
Percentage for time accuracy claim       
 
Operating conditions 
I.   
Relative humidity  Humidity (RH) 95% maximum 
II.   
Operating temperature range   -25 ºC to +55 ºC   
III.   
Storage temperature range  -25 ºC to +70 ºC  
I.   
AC current input terminals   M3.5 threaded terminals for ring lug connection. Suitable up to 4 mm
2  
 
II.   
Auxiliary & input/output 
Terminals  
M3 threaded terminal connection. Suitable up to 2.5 mm
2  
 
 
III.   
Tightening torque for M4/M3 
screws 
IV.   
Rear communication terminal  
Two wire connection. Suitable up to 2.5 mm
2
Mechanical & Environmental specification
 
I.   
II.   
III.   
2.1.1  Standards Compliance 
 
SR. 
TYPE TEST   STANDARD  TEST SPECIFICATION/METHOD 
1.  Impulse, Dielectric and Insulation tests 
1.1  Impulse voltage test 
IEC 60255-27:2005  
(incl. corrigendum 2007) 
Test voltage  5kv, 1.2/50 µV 
Energy  0.5 J 
Polarity  +ve and –ve 
No. of impulses  3 on each polarity 
Duration between impulses