Siemens siprotec 7SA6 User Manual

Technical Data
10-40 7SA6 Manual
C53000-G1176-C156
10.18 Thermal Overload Protection
Setting Ranges Factor k according to IEC 60255–8 0.10 to 4.00 (steps 0.01)
Time factor
τ 1.0 min to 999.9 min (steps 0.1 min)
Alarm temperaturerise
Θ
alarm
/Θ
trip
50 % to 100 % related to the trip
temperaturerise (steps 1 %)
Current alarm stage I
alarm
0.10 A to 4.00 A
1
) (steps 0.01 A)
1
) Secondary values based on I
N
=1A;forI
N
= 5 A they must be multiplied with 5.
Calculation
Method
Calculation method temperaturerise maximum temperaturerise of 3 phases
means of temperaturerise of 3 phases
temperature rise from maximum current
Tripping
Characteristic
seeFigure10-6
Drop-off
Ratios
Θ/Θ
trip
drop-off with Θ
alarm
Θ/Θ
alarm
approx. 0.99
I/I
alarm
approx. 0.95
Tolerances Relating to k · I
N
2%,or.10mA
1
); class 2 % according to
IEC 60 255–8
Relating to
Tripping time 3%,or.1s; class3%accordingto
IEC 60 255–8 for I/(k ·I
N
)>1.25
1
) Secondary values based on I
N
=1A;forI
N
= 5 A they must be multiplied by 5.
t τ
I
k I
N
⋅
-------------
èø
æö
2
I
pre
k I
N
⋅
-------------
èø
æö
2
–
I
k I
N
⋅
-------------
èø
æö
2
1–
-------------------------------------------------
ln⋅=
Tripping characteristic
t Tripping time
τ Temperature rise time factor
I Load current
I
pre
Previous load current
k Setting factor according to
IEC 60255–8
I
N
Rated current of protected object
Meaning of abbreviations:
for (I/k· I
N
) ≤ 8

Siemens siprotec 7SA6 Specifications

General

Brand	Siemens
Model	siprotec 7SA6
Category	Relays
Language	English