7300w² Monitor Instruction Manual
All WaterWatch² sensors and Expansion Boxes communicate with the monitor using the ModTechw²
Protocol. This is a modified Modbus Protocol and has been specifically developed to take advantage
of the advanced features and diagnostics designed into the w² range of sensors.
Note: These sensors can
NOT
be used with other monitors that are not included in the w² family.
All sensors within the w² family of instruments are connected to the 7300w² Monitor using the same 4 wire
configuration, however some slight variations may occur with specific sensors. Always check the manual
supplied with the sensor to ensure the correct termination is applied.
•
RED and BLACK wires provide the 12VDC supply to the sensor and the communication ground.
•
WHITE and GREEN provide data communication.
A maximum of two sensors can be directly connected to the standard 7300w² Monitor, however additional
sensors can be added using optional Expansion Boxes available separately.
Remove the 4-way connector from the 7300w² Monitor by pulling downwards to disconnect for easy access
to the connections. Connect the sensor cores as follows:
(Terminals from left to right on the 4 way connector)
Term 1 (Left)
-
RED (+12V)
Term 2
-
Black (0V) and Drain
Term 3
-
White (Data A)
Term 4 (Right) -
Green (Data B)
Always connect the screen drain wire with the Black (Term 2). Illustration Left shows drain wire and Black
wire connected together, and covered in Black Heat shrink.
Always use Bootlace ferrules when terminating the sensors to ensure a good connection to the terminals.
4.4.5 Extending Sensor Cables
Sensors are usually supplied with 10m cables (longer cables can be provided on request). These cables can
be extended to a maximum length of 100m. To ensure optimum performance, we advise the use of Partech
ModTechw² cable for extensions. Partech can supply Junction Boxes to allow for easy termination of cable
extensions. These should be used on all installations where the cable length from the sensor to the monitor
exceeds 20M (Partech Junction Boxes include on-board filtering for long cable lengths). Junction Boxes are
also useful for local connection of sensors close to the sample point. This permits easier replacement of
sensors without the need to pull back cables to the monitor. The Junction Box has an on-board terminator
switch that can be activated to terminate the network if the sensor is to be removed for long periods.
When joining cables, ensure the connection is fully waterproof. Any moisture ingress can effect the
performance of the sensor and monitor. Always ensure the earth screen is continued when making joints.
ModTechw² Cable specification:
•
2 Twisted Pair: Red/Black (Power) and Green/White (Data) with Screen and Drain wire
•
Cores 24AWG (0,22mm²) 7 x 0,20mm
•
Outer Insulation: PUR Polyurethane Blue (RAL5003), Diameter – 5mmØ
224081IM Issue 22 Issue Date 27/03/2018
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