User guide

UNITY DAU Installation & Maintenance Manual
Speaker Circuits
Unity has two speaker Circuits, A & B. to fully comply with the requirements of EN60849 the speakers
should be wired in an interleaved pattern, so if one circuit fails messages can still be heard in the areas
covered (note it is accepted practice to only place one speaker in an office, as long as the connecting
corridor is on the other circuit).
Each output of UNITY can support 30W of speakers, this is typically five 6W speakers, ten 3W speakers
or twenty 1.5W Speakers.
6W speakers are generally fitted in noisy offices or reception areas, 3W speakers are usually used in
corridors, and 1.5W speakers in small rooms or open plan offices.
Caution Speaker circuits carry 100V AC
Disconnect before servicing to prevent Shock hazard.
Speaker Circuits on Unity are DC monitored.
Suitable speakers for Unity MUST have a thermal fuse to disconnect the speaker if it is in the
area in fire and a DC blocking capacitor fitted, typically the capacitor is 2.2uF 250V DC.
The wiring goes through each speaker, and in the last speaker the end of line resistor. Each circuit can
have 2 spurs, the DAU is provided with two end of line resistors per circuit, both must be fitted to avoid
faults being shown on the panel. If only one spur is used per circuit, one resistor resides in the panel;
one resistor resides in the last speaker on the circuit.
Before connecting the speaker lines to UNITY count the number of speakers and note the tapping they
are set at, (most manufacturers will supply speakers at the maximum tapping, or at the half power
tapping) this value should not exceed the 30W rating of the UNITY DAU for a single circuit.
Document DCC UND 7001-01 Rev 1 June 2005 Page 10 of 17