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A typical application for these bell transformers is short-time use, i.e. bells, gongs, door openers or remote control switches in residential buildings.
The standard EN 61558 distinguishes between transformers for short-time loading and those for permanent loading. This means that clear requirements for bell transformers are defined. A bell transformer must maintain 100 % of its rated power for 1 minutes or 20 % for 5 minutes, without shutting down.
Siemens bell transformers are protected against short circuit or moderate overload by a PTC resistor. If a disconnection occurs, the bell transformer must be switched off for approx. 30 minutes to cool down the PTC resistor.
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.
The transformers are IMQ and VDE approved – this ensures safety in use.
The electronic power supply unit provides a 24 V DC supply to systems with an operational voltage of 85 to 265 V AC or 85 to 300 V DC. The device operates in the lower class for minimum power supply with a safety extra-low voltage. In the event of short circuits and high capacitive loads, the power supply unit detects the overcurrent as soon as it is activated and shuts down immediately. It switches back on after 2.5 seconds. The electronic power supply unit is suitable for supplying the 5TT7 1 GSM alarm modules within a supply voltage range of 150 to 230 V AC. Power supply units for direct voltages with rectifiers are used to supply gongs, bells, door openers, switching relays, remote control switches, Insta contactors or for safety extra-low voltage systems (SELV) in continuous operation. They are protected against short circuit or moderate overload by a PTC resistor. If tripped, the power supply unit must be switched off for approx. 30 minutes to allow the PTC resistor time to cool down.
Electronic power supply unit
Power supply units with bridge rectifiersThe power supply units are IMQ and VDE approved. This ensures continuous operation
Bells and buzzers are typically used in residential buildings and non-residential buildings, such as shops, offices, banks, etc. They are used to indicate alarm states or for general acoustic signaling.
Bells and buzzers are used as modular installation devices in distribution boards. These devices are designed for short-time use in compliance with IEC 62080.
Reliable device protection through PTC; for protection against overload and short circuits.
The socket outlets for mounting in distribution boards acc. to DIN 43880 and on standard mounting rails acc. to DIN 60715 have since become standard in modern switchgear assemblies/distribution boards. They are used for tasks such as the connection of plugin communication devices in communication distribution boards, in switchgear assemblies for maintenance purposes or in private plants for the occasional use of devices with heavy starting and separate fusing. The socket outlet range complies with a number of different standards and is available according to the standards of the following countries: VDE for Germany, CEE7 for Belgium/France, CEI for Italy and UL for USA.
In distribution boards with 55 mm mounting depth the socket outlet can only be used without the hinged lid. The lids can be retrofitted on all devices. To make installation easier, the touch-protected terminals L, N and PE are located on the side of the socket outlet.
In plant sections where equipment is still current-carrying, even after the main switch has been disconnected, this must be indicated acc. to DIN VDE 0105-1 and IEC/EN 60204-1/ DIN VDE 0113-1. Yellow socket outlets are used for these applications.
By pulling on the hinges, the hinged lid stays open at more worldwide application. than 180°. This facilitates manual insertion of connectors.