Wiring; Installation Of Sig.processor; Selecting Location - JRC JLN-900 Installation And Instruction Manual

1 General
The purpose of this section is to provide enough information to have a good and reliable
installation of the NJC-80 Sig.Processor in the JLN-900 Log system.
WARNING
This unit contains electrostatic sensitive devices.
Observe precautions for handling.
Note that this is only one of the manual sections needed for installation. A special and
completely stand-alone section prior to this describes the important issue of installing the
bottom parts and transducer. It should be noted that a good transducer installation is of
primary importance for achieving good performance of the log system. Selecting correct
transducer location shall be done in cooperation with JRC and JRC must approve the selected
location!
1

Wiring

Depending on how the order was placed, a ship's specific wiring diagram may be delivered
with this manual. If not, a typical wiring diagram is included.
In general, it is sufficient to fulfil some simple rules for having good electrical connections
within the system.
The Sig.Processor shall be firmly grounded to the ship's structure.
All wires shall be electrically shielded and all signal wiring shall be twisted pairs.
For IEC 61162-1/NMEA, a cross-section of 0.50 mm² is electrically sufficient, although
dimensions like 0.75 mm² or more are more common in shipyards.
2

Installation of Sig.Processor

2.1

Selecting location

An obvious requirement for selecting a good location is the standard 30 m cable to the
transducer. This cable must have no joints via any junction box of any kind, but be connected
directly from the transducer! The Sig.Processor is designed to operate in an environment
fulfilling the requirements specified in the section "Technical Specification". Recommended
conditions for the chosen location are listed below:
The location should be easily accessible for transducer replacement, calibration or other
service.
The location should be protected from weather and should offer a stable temperature not
outside the range 0 - 55°C.
The location should not expose the unit for excessive vibration levels.
The location should be far from electrical installations giving excessive electric and/or
magnetic fields, such as powerful electrical motors for ventilation, bow thrusters etc.
There must be a reasonably good way of laying the 30 m cable to the transducer in such a
way that it is possible to replace for transducer replacement.
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