Comelit ILS-2, Manual

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3.1 Connection to external devices
Figure 3-1: terminal block for connection to external devices
3.1.1 Connecting the Batteries / Power supply input
Figure 3-2: Ferrite core
ILS-2 must be powered by means of a 24 Vdc power supply unit with EN54-4 approval. The power supply must
be connected using the BATTERY terminals on board the terminal block, observing the correct polarity. The
minimum recommended size is 16 x 0.25 mm (18 AWG), or greater if the power supply unit is further than 5 m
away from the sensor.
A ferrite core is supplied to ensure correct electromagnetic compatibility (EMC). This core must be positioned
inside the unit and the power supply cables wound as shown in figure 3-2. The type of power supply unit required
depends on the speed of the fan used for the application; please refer to Table 11-2: Current Consumption vs Fan
Speed.
3.1.2 ACTION 2, ACTION 1 - Relay output
The voltage-free contacts of the relay ACTION (ACTION) will change status when the pre-alarm level is
exceeded. The Normally Open (NO) and Normally Closed (NC) contacts on the terminal block are available.
3.1.3 FIRE 2, FIRE 1 - Relay output
The voltage-free contacts of the relay FIRE (FIRE ALARM) will change status when the alarm level is
exceeded. The Normally Open (NO) and Normally Closed (NC) contacts on the terminal block are available.
3.1.4 FAULT 2, FAULT 1 - Relay output
In fault conditions, the FAULT relay will change status. The Normally Open (NO) and Normally Closed (NC)
contacts on the terminal block are available.
Note: NO/NC shown in the terminal block refers to the un-powered sensor status. In normal operating
conditions (power supply present) the NO contact is closed, while the NC contact is open.