BusinessPhone Communication Platform 4.0
Installation Instruction ASB 150 02

## Door Interface Unit (DIU) (BFY BS 10101/1)

### Installation

The DIU is an interface connected via one or two extension lines to the ELU-A of the exchange and via a set of wires to the door phone. The DIU should be mounted indoors on a dry wall. The door phone can be of any commercially available type as long as it meets the requirements listed in the System Overview (1555-ASB 150 02 Uen) under “Technical Data for DIU”.

### Connection

The wires to the speaker and microphone should be led via two twisted pairs in a separate cable. Caution when connecting a polarity-dependant microphone. Check polarity on connector x1. Make the connections to the door bell button, door opener and key lights etc in another cable. This is to minimise disturbances on the microphone line. The wires to the door opener carry more current and should have a diameter greater than 0.6 mm. The length between door phone and DIU should be less than 50 m. The length between door phone and exchange should be less than 500m.

The connector X18 is used for speech connection between DIU and exchange. The connector X17 is used to activate the door opener. If the door opener wiring already exists the X17 connection can be omitted and the connection X12 leads to an existing button.

Pressing the door phone button (connection X5) activates the DIU and the programmed extension rings (see Facility Description, 15534-ASB 150 02 Uen). The interface stays active for the preset time selected under "C" and shuts off after this time has elapsed.

### Adjustments of DIU

The microphone level is factory set, but under certain conditions the line attenuation can exceed expectations resulting only in one way speech connection or clipping of the voice between extension and door phone. In this case cautious change of microphone level setting has to be performed. The potentiometers range is

- If the voice in the speaker of the door phone sounds too dim or is clipped, turn the mic potentiometer screw two turns counter clockwise. Speak into the telephone microphone and verify that the speaker sounds loud and clear enough other wise repeat the procedure.
- No voice connection to the speaker of the telephone.Turn the mic potentiometer screw two turns clock wise. Speak into the door phone microphone and verify that it is heard in the hand set of the telephone otherwise repeat again.

### Settings on the board

Revision: A © Ericsson Enterprise 2003