
IPC402x-UM-2209-1-2.x.x (en)
Ensto Protrol AB
Phone: +46 31 45 82 00
Alfagatan 3
internet: www.protrol.se
431 49 Mölndal, SWEDEN
46
e-mail: [email protected]
8.5 Detector Settings
– Detector n
8.5.1 Overcurrent
IPC402x has two overcurrent steps that operate independently of each other. Overcurrent
Enable
means
that both steps are activated. The start signal is common. This means that
START
overcurrent is generated
by either step 1 or step 2 starting. The overcurrent function measures the RMS value of all phases. Inverse
time characteristics can be activated for step 1 using the parameter
Enable
.
The
START
signal is generated if the current in a phase exceeds the set levels,
Level 1
or
Level 2
.
TRIP
overcurrent is generated after the set time delays,
Delay 1
or
Delay 2
. If the setting
Input qualifier
is
selected to any input, 1-16, no
TRIP
output signal and message to remote control will be created until there
is voltage on the selected input within set time,
Event delay
. However, the internal event is always
generated.
If inverse time characteristics is used,
Delay 1
is ignored and is replaced with a calculated delay time
according to IEC 60255,
𝑡 = 𝑇𝑀𝑆 × (
𝑘
(
𝐼
𝐼
𝐿𝑒𝑣𝑒𝑙 1
)
𝛼
− 1
)
Where
TMS
is a parameter of own choice and
k
and
α
are defined by the choice of inverse curve according
to the following table.
Curve type
k
𝜶
Standard inverse
0,14
0,02
Very inverse
13,5
1
Extremely inverse
80
2
Long inverse
120
1