Installation guide

22 Raymarine DSM400 Digital Sounder Module
2.7 Ground connection
Power input cable
Your DSM400 Digital Sounder Module is designed for use on
boat’s with a ‘negative’ ground system and is not intended for
use on boat’s with a ‘positive’ ground system.
It is important that an effective RF ground is connected to the
system. A single ground point should be used for all equipment.
You can ground the sounder unit by connecting the drain wire
(shield) of the power input cable to the boat’s RF ground.
If you need to extend the wire, the extension wire should be an 8
mm braid or AWG 10 multi-stranded cable. If your boat does not
have and RF system, connect the drain wire to the negative
battery terminal.
The boat’s DC power system should be either:
• Negative ground, with the negative battery terminal
connected to the boat’s ground, or,
• Floating, with neither battery terminal connected to the
boat’s ground.
Transducer cable
To ensure an efficient ground for the transducer cable(s) you
should carry out the following:
1. Gather the external shield wires from the transducer cable(s)
and twist the free ends together.
2. Insert these twisted ends into the connector of the ground
spur.
3. Using a suitable tool, crimp the twisted ends into the ground
spur connector.
Terminal Function Color
+ Battery positive Red
Ground Shield (drain wire) No insulation
- Battery negative Black
POWER
GROUND
Br Wh Gr
Red Screen Black
D10992-2
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DSM400 Installation Guide.book Page 22 Tuesday, November 4, 2008 4:53 PM