STWA1
12050-0701-00
Page
3 / 4
www.ziehl.de
5
Connecting diagram
See operating manual of ZIEHL current relays type STW.
Attention!
There may only one conductor be lead through the transformer!
Attention!
The connecting cable can be extended up to 50 m. When laying parallel to
power cables use twisted or shielded cables.
Attention!
The polarity of the current transformer output (white marking on the cable) must be
observed only if several current transformers are connected in series to increase the
sensitivity.
5.1 Tips
Limit too high
(current in wire too low):
•
Loop through wire several times
Limit too low
(small loads shall not be recognized)
•
Connect a resistor (0,25 W / 200 V) in parallel to the current transformer STWA1(H)
➢
- - resistor 750 Ohm = enhancement by factor 2x
➢
- - resistor 330 Ohm = enhancement by factor 4x
➢
- - resistor 150 Ohm = enhancement by factor 10x
Because of high tolerances we recommend to determine the best value by try out.
6
Technical data
Input / primary conductor
Rated thermal continuous current Icth
AC 100 A
Thermal rated short-time current Ith
AC 300 A for 10 s
Rated frequency
50/60 Hz
Max. Operating voltage Um
0.72 kV
Output
Max. output voltage U at Icth = 100 A
200 V peak (not limited)
Max. short circuit current I at Icth = 100 A
140 mA eff.
Test Conditions
EN 61010-1
Type test voltage
AC 2500 V 50 Hz 60 s
Installation conditions
Permissible ambient temperature
-25 °C ... +70 °C