407 / 582
BETA Switching
Transformers, Bells and Socket Outlets
4
AC3 4 ... 4AC3 6
transformers for permanent loads
10/5
Siemens ET B1 · 10/2008
10
■
Overview
These transformers up to 63 VA provide a safety extra-low voltage
(
SELV) for the supply of control circuits, switching relays and
Insta contactors in continuous operation as an AC voltage/
current supply for 8, 12 or 24 V AC.
Siemens transformers for permanent loads are protected
against short circuit or moderate overload by a PTC resistor. If a
disconnection occurs, the transformer must be switched off for
approx. 30 min to allow the PTC resistor to cool down.
EN 61558-2-2 specifies that the difference between the non-loaded
output voltage and the output voltage loaded with the rated load
for transformers for permanent loading must not exceed 10 %.
This requirement places the highest demands on the design of
this type of transformer. It can only be met by using high-quality
core materials and a core design with an extraordinarily high
efficiency, such as type EI according to DIN 41302.
■
Benefits
•
The transformers with 24, 40 and 63 VA cores are molded,
which means that they are hum-free and suitable for installation
in sound-sensitive distribution boards
•
Reliable device protection through PTC; provide longstanding
protection against overload and short circuits
•
The transformers are IMQ and VDE approved – this ensures
safety in use.
■
Technical specifications
4
AC3 408 4AC3 516 4AC3 524 4AC3 540 4AC3 616 4AC3 624 4AC3 640 4AC3 663
Standards
EN 61558-2-2
Approved acc. to
EN 61558-2, IMQ
Rated operational power P
s
VA 8
16
24
40
16
24
40
63
Rated short-time power
p.f. = 0.5; t = 10 s
VA 10
18
27
48
18
27
48
80
Rated operational voltage U
e
V AC 230
Operating range
at 50/60 Hz
× U
e
0.9 ... 1.1
Rated frequency
Hz 50
Range of operating frequency
Hz 48 ... 62
Rated secondary voltage U
sec
V AC 8
2
× 4
8
2
× 12
In series connection
V AC No
8
No
24
Rated secondary current
I
sec
•
At 4 V
A AC No
2
× 2
No
•
At 8 V
A AC 1
2
3
5
No
•
At 12 V
A AC No
2
× 0.67 2 × 1
2
× 1.67 2 × 2.62
•
At 24 V
A AC No
0.67
1
1.67
2.62
Rated power dissipation P
V
•
In no-load operation
VA 3.5
10.3
8.0
13.8
8.0
13.1
8.3
23.0
•
At rated load
W 2.6
4.6
2.7
6.9
3.6
6.3
5.7
10.0
Hum-free
Core molded
No
Yes
No
Yes
Safe isolation
Creepage distances and clearances
mm 3
Insulation class
B
Test voltage, 50 Hz 1 minute
Primary against secondary winding
kV
4
Terminals
± screw (Pozidriv)
1
Conductor cross-sections
•
Rigid
mm
2
1 ... 6
•
Flexible, with end sleeve, min.
mm
2
0.75
Permissible ambient temperature
In operation
°C -10 ... +40
Permissible humidity
% 80
Degree of protection
Acc. to EN 60529
IP20
Safety class
Acc. to EN 61140/ VDE 0140-1 II
© Siemens AG 2008