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Whilst every effort has been made to ensure the accuracy of our data sheets at the time of publication, we reserve the right to supply equipment in line with current design specifications and recommend that critical parameters are checked at the order stage.


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Switching Modules

Elvox Audio Door Entry Expansion Modules Series 839

Elvox 839 Series Expansion Modules

This range of switching modules is used whenever it is necessary to add more door stations to a single door system (drawings c2328, c2633 and c1961). It is possible to cascade these 2 and 3 door modules (839/302 and 839/303) to connect additional doors stations by connecting one of the door station terminals of one switching module to the input (PSU) terminal of a second switching module and so on. A combination of one 303 and one 302 or of three 302s in cascade will give a maximum of four door stations operating in the system. This combination of switching modules should at first glance connect up to five door stations but one set of door station contacts is used each time one switching module is connected to another. The maximum number of door stations that can be operated by connecting three 303s in series is, therefore, seven. If more door stations are required, ie. more switching modules are needed in a system, then the switching modules must be connected in a different way (see drawing 'multi-door PM839RO'). This drawing shows 12 entrance panels connected to a cascade of 302 and 303 switching modules. The fact that an existing conversation between a handset and door station will be interrupted as soon as another door station is called, means that the more door stations that are connected, the more impractical such a method of working may become. The total volume of traffic at any one time is, therefore, an important factor when using this type of configuration.

For busy, multidoor systems, the use of the video switching module 6592, which does not have call interruption, but uses 'busy' lights instead or one of our concierge switchboards should be discussed with our technical sales staff.

  • Compact size.
  • DIN rail or surface mounting.
  • Terminal safety covers.
  • Many applications.
  • Type 839/302 - Used when a second door station is required. It switches the power of the PSU to whichever door station is last called. 8-DIN case.
  • Type 839/303 - Used to connect three door stations to the PSU. It switches the power of the PSU to whichever door station is last called. 8-DIN case.
  • Type 839/837 - Used for 1+1 wire DE system (1common wire + 1 wire per handset) with 2 door stations. Connects to either PSU 6837 or PSU 837/OCT. 12- DIN case.
  • Type 839/402 - Used for 2 door stations and switchboard Type 152. 8- DIN case.

# 68 : Mod 09/03/09