C-212 Parameter Reference 
AC30 series Variable Speed Drive 
Stack Inv Time 
Parameters::Motor Control::Stack Inv Time 
 
The purpose of the inverse time is to automatically reduce the drive current limit in response to prolonged overload conditions. 
 
For a short time given by Short Overload Time, the drive is able to provide the Short Overload Level 
For a long time given by Long Overload Time, the drive is able to provide the Long Overload Level 
 
These 2 protections work in parallel, the output limit current  is the maximum value if Inv Time Active = False.  If Inv Time Active = True, the 
current limit is determined by Long Overload Level 
the current limit is not yet ramped down. If already ramped down, the current limit is due to the long overload. 
 
When the maximum overload value is reached, the inverse time current limit is ramped down. The rate at which the inverse time current limit is 
ramped to the Inv Aiming Point is defined by Inv Time Down Rate. When the overload condition disappears, the inverse time current limit is ramped 
up. The rate at which the inverse time current limit is ramped to the maximum value is defined by Inv Time Up Rate. 
 
% Are all referring to drive/stack ratings. 
 
100% Stk Current 
 
0343 
 
Parameters::Motor Control::Stack Inv 
Time 
x.x 
 
0.0 to 10000.0 
 
A 
 
NEVER 
 
Stack rating in rms amps corresponding to 100% stack current 
Long Overload Level 
 
0344 
 
Parameters::Motor Control::Stack Inv 
Time 
x. 
 
0 to 200 
 
% 
 
NEVER 
 
Overload value in % of the stack amps for long overload condition(*) 
Long Overload Time 
 
0345 
 
Parameters::Motor Control::Stack Inv 
Time 
 
 
0.000 to 100000.000 
 
s 
 
NEVER 
 
Maximum duration under long overload condition (typically 60s)