Technical description
3 Supporting functions
3.3 Cold load pick-up and inrush
current detection
VM259.EN007
VAMP 24h support phone +358 (0)20 753 3264
153
No activation because the current has not been under the
set I
dle
current.
Current dropped under the I
dle
current level but now it
stays between the I
dle
current and the pick-up current for
over 80ms.
No activation because the phase two lasted longer than
80ms.
Now we have a cold load activation which lasts as long as
the operation time was set or as long as the current stays
above the pick-up setting.
Figure 3.3-1 Functionality of cold load / inrush current feature.
Parameters of the cold load & inrush detection function
Parameter
Value
Unit
Description
Note
ColdLd
-
Start
Trip
Status of cold load detection:
Cold load situation is active
Timeout
Inrush
-
Start
Trip
Status of inrush detection:
Inrush is detected
Timeout
ILmax
A
The supervised value. Max. of
I
L1
, I
L2
and I
L3
Pickup
A
Primary scaled pick-up value
Idle
A
Primary scaled upper limit for
idle current
MaxTime
s
Set
Idle
xIn
Current limit setting for idle
situation
Set
Pickup
xIn
Pick-up setting for minimum
start current
Set
80
ms
Maximum transition time for
start recognition
Pickupf2
%
Pick-up value for relative
amount of 2
nd
harmonic, I
f2
/I
f1
Set
Set = An editable parameter (password needed)