Furuno LH-3000CG Operator's Manual page 16

1. INSTALLATION
Floating ground
The LH-3000 has a floating ground. What this means is that the heat sink ground is floating
and will not ground batteries if they are connected to the ship's chassis. To maintain a
floating ground:
1. Use a stereo plug when connecting a 4 ohm speaker to the external speaker plug.
Connect it as shown in the illustration below.
2. Do not connect any of the output connectors on the rear panel to the ship's ground.
3. SP outputs are floating and must not be connected to either battery or the rear panel.
Use a normal two conductor insulated speaker wire for the horn speaker.
Siren mode switch (for LH-3000-CG)
To use the siren mode function, connect a toggle switch whose specifications are as shown
below to the burglar alarm terminal.
LH-3000C
ALRM
Toggle switch specifications
Circuit:
Switching function:
Rating:
Insulation resistance:
Voltage breakdown:
Contact resistance:
8
Do not use for battery -
use for ship's earth only
Stereo plug
J3
4
5
SPDT (3P)
ON-OFF-ON
6A, 250 VAC
500 VDC, 100 Mohms min.
1500 VAC (one minute)
less than 20 Mohms max.
SIREN
OFF
ALARM
Alarm SENSOR