MC30-R2
Doc. N°
MO-0462-ING
Copyright 2012
FW: 1290.37.01.x
Date
06.09.2022
Rev.
1
Pag.
10
of
38
3. Functions and Settings (Function)
The relay is provided with two groups of setting
“
” and “
”.
Group Functions
T>, I>, I>>, IH, Io>, Io>>, IoH, BF, IRF, RCL, Osc, Comm, LCD.
T>, I>, I>>, IH, Io>, Io>>, IoH, RCL.
3.1 - T> (F49) - Thermal Image protection level
FuncEnab
→
Enable
[Disable / Enable]
Options
→
No Param
No Parameters
TripLev
→
Tal
50.00
%Tb
(50.00
110.00)
step 1
%Tb
→
Tst
100.00
%Tb
(10.00
100.00)
step
1
%Tb
Timers
→
No Param
No Parameters
Description of variables
FuncEnab
: If disable the function is disactivated.
Tal
: Thermal prealarm temperature.
Tst
: Reset level.
Warming-
up is computed proportionally to the square of the largest phase current “
I
”.
-
Allowed overloading time
(See Curve)
The trip time delay “
t
”
of the thermal element, depends on the warming-up time constant
“
tw
”
, on the previous thermal status (Ip/In)
2
, on the admissible continuous overload (Ib) and, of
course, on the actual load (I)
tw
=
Warming-up time constant
(1-60)min.
I
=
Largest of the three phase currents
Ip
=
Preheating current: Steady-State Current corresponding to the thermal status
existing at the moment when the current is increased to the overload value “I”
Ib
=
Continuously admissible current
(50-130)%In, step 1%In
In
=
Rated primary current of phase C.Ts
n
=
Natural logarithm
Reset takes please when the simulated temperature drops below the programming level [Tst].
An alarm signal is issued when the computed warmi
ng exceeds the set percentage “
Tal
”
of the Full
Load temperature “
Tb
”.
:
where
(Ib/In)
(I/In)
(Ip/In)
(I/In)
tw
t
2
2
2
2
−
−
=
n
