Bosch PRAESENSA, Installation Manual

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100 en | End-of-line device | PRA-EOL PRAESENSA
2019.11 | V1.00 | Installation manual Bosch Security Systems B.V.
10.5.2 Wiring
The end‑of‑line device must be connected to the end of a loudspeaker line, to monitor the full
length of the line. All loudspeakers connected to that line must be wired in a loop‑through
arrangement, without branches. The end‑of‑line device is then connected to the last
loudspeaker using the supplied connection wire.
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To do so:
1.
Cut (1) the supplied connection wire with the thermal fuse in two halves.
2. Connect the two wires to the 100 V or 70 V loop‑through connection of the loudspeaker,
with the thermal fuse at the loudspeaker side:
–
This is the primary side of the loudspeaker transformer.
– The polarity is not important for the end‑of‑-line device, but it is good practice to
connect the wire with the thermal fuse to the positive loudspeaker terminal.
– The thermal fuse is to disconnect the end‑of‑line device and its wires from the
loudspeaker line in case of fire. This prevents that the loudspeaker line might be
shorted in case the wire insulation melts.
3. Cut the wires (2) to the required length for connection to the end‑of‑line device, feeding
the wires through the strain relief slot (3) in the plastic housing:
–
The end‑of‑line device uses a 2‑pole push wire connector.
– The stripped wire ends must be inserted into the connector completely, up to the
insulation, to prevent that the wires can be touched.