Thermal Overload Protection T> (49F) - VAMP 140 Operation And Configuration Instructions

VAMP 140
2.2.5.
16
Overcurrent and earth-fault relay
Technical description
Setting parameters of second harmonic blocking:
2.Ha (68)
Parameter: Value:
If2> 10...100
t_f2 0.05...300.0
S_On
Enabled;
Disabled
S_Off
Enabled;
Disabled
T_On
Enabled;
Disabled
T_Off Enabled;
Disabled
Measured and recorded values of second harm. blocking:
2.Ha (68)
Parameter: Value: Unit: Description:
Measured IL1H2.
values
IL2H2.
IL3H2.
Recorded Flt
values
EDly
Thermal overload protection T> (49F)
The overload function protects the line against thermal
overload. The thermal stress can be supervised by means of a
thermal image, which can be calculated from the standard
heating expression according to IEC 60255-8:
−
2
I I
τ
= ⋅
t ln
−
2
I ( k *
where:
t =
τ =
I =
ln =
Ip =
k =
I =
n
Vamp 24h support phone +358 (0)40 573 6316
Unit: Default:
% 10
s 0.05
- Enabled Start on event
- Enabled Start off event
- Enabled Trip on event
- Enabled Trip off event
% 2. harmonic of IL1, proportional
to the fundamental value of IL1
% 2. harmonic of IL2
% 2. harmonic of IL3
% The max. fault value
% Elapsed time as compared to the
set operating time; 100% =
tripping
2
p
2
I )
n
trip time
thermal time constant of cable
average RMS value of three measured
phase currents
natural logarithm
preload current (corresponds to the heating
level reached)
factor for allowed continuous overload
rated current
VAMP Ltd
Description:
Setting value If2/Ifund
Definite operating time
VM140.EN011