BRTSys Modbus Salinity Sensor Adapter Datasheet

1 Introduction

The Modbus Salinity Sensor Adapter is designed to work with a Salinity probe to form a complete Salinity sensor. It uses the electrical conductivity method for its measurement. This adapter has a BNC connector for attaching the Salinity probe. A 2-point calibration method is used to calibrate the adapter and probe and allows measurements of salinity between 1 ppt and 120ppt with a precision of 1ppt. These adapters and probes are suitable for use in applications such as aquaculture fishponds, shrimp ponds, sea water applications, nutrient tanks, water treatment plants, and swimming pools.

1.1 Features

• Salinity Sensor Adapter to integrate with cell constant K=10 Salinity probe with BNC connector
• Measures Salinity range of 1ppt to 120ppt with linearized output and 1ppt resolution
• 2 Point calibration
• Implements Modbus RTU protocol
• High report rate of every 5 seconds
• Low power consumption 5V-91mW
• Operating temperature range: 0°C to +70°C
• Flush mount and DIN Rail Mount options

Visit https://brtsys.com/resources/ for more information.

Certifications: CE, FCC, REACH, RoHS Compliant

2 Part Numbers / Ordering Information

3 Specifications

4 FCC Compliance Statement

This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:

1. These devices may not cause harmful interference, and
2. These devices must accept any interference received, including interference that may cause undesired operation.

NOTE: The equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If the equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Re-orient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.

To maintain compliance with FCC's RF exposure guidelines, at least 20cm of separation distance between the device and the user's body must be always maintained.

FCC Radiation Exposure Statement

This device complies with FCC radiation exposure limits set forth for an uncontrolled environment and it also complies with Part 15 of the FCC RF Rules. This equipment must be installed and operated in accordance with the instructions provided, and the antenna(s) used for this transmitter must be installed to provide a separation distance of at least 20 cm from all persons and must not be co-located or operating in conjunction with any other antenna or transmitter. End-users and installers must be provided with antenna installation instructions and consider removing the no-collocation statement.

Caution

Any changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

The FCC logo is displayed.

5 Hardware Features

The Modbus Salinity Sensor Adapter features:

• BNC Connector: For connecting the Salinity Electrode Probe (not included).
• System Status LED Indicator: Provides visual feedback on the device's status.
• RJ12 Port: Modbus data and power interface port.
• Flush Mount Slot: Allows for direct mounting on a wall or flat surface.
• DIN Rail Plate: For mounting on a standard DIN rail using an optional mount set.

6 Sensor Adapter Configuration and Installation

Please visit https://brtsys.com/resources/software/utility-tools to access the Modbus Configuration Utility guide on how to configure the device name, device address and termination settings before using it for your specific application.

6.1 Connection Diagram for Standard Modbus Power Supply

The diagram shows a Modbus network setup:

• Device 1 (Modbus Host Controller): Connected via Twisted Pair Cable.
• Device 2 (Modbus Device): Connected via RS485-RJ11 Cable or RS485-JST Cable.
• Device 3 (Modbus Device): Connected via RS485-RJ11 Cable or RS485-JST Cable.
• Connections include RS485 A, RS485 B, Ground, and 9-24VDC VIN.

Setup Instructions:

1. Use a Cat5e/Cat6e RJ45 Twisted Pair Cable to connect the Modbus controller (Host) to the network for RS485 communication and power.
2. Connect each Modbus device to the network using either an RS485-JST cable or an RS485-RJ11 cable, as provided with the device.
3. BRTSys Modbus devices have built-in bus termination resistors. These resistors can be enabled or disabled by using the BRTSys Modbus Configuration Utility. When installing the device as the last device on the bus, these terminations may be used to terminate the bus.

6.2 RS485-RJ11 Cable(30cm)

The RS485-RJ11 cable has an RJ11 connector on one end and an RS485 Modbus interface on the other. The pin configuration is as follows:

7 Mounting Instructions

7.1 Flush Mount

The device can be flush mounted directly on a wall or any flat surface using 2 M3.5*16mm (thread) screws.

A diagram shows the adapter with screw holes labeled '2xM3.5*16mm'.

7.2 DIN Rail Mount

The device can be mounted on a DIN Rail using the LDSBus DIN Rail Mount set. This set is optional and includes the bracket and mounting screws.

A diagram shows the adapter mounted on a DIN Rail.

8 Modbus Registers

The following table details the Modbus registers for the adapter:

9 Mechanical Dimensions

All dimensions are in millimetres.

Diagrams show the top, side, and bottom views of the adapter with dimensions:

• Top View: Length 117.6mm, Width 42.9mm.
• Side View: Height 29.7mm.
• Bottom View: Mounting hole spacing 60.0mm.

10 System Status LED Indicators

The system status LED indicates the device's operational state:

Note:

1. For reliable communication, ensure that the power supply and the RS485 termination settings are correct.
2. Ensure that the Modbus address and baud rate are configured correctly before deployment.

11 Probe Selection

The following specifications are recommended for selecting a Probe:

• Detection Range: 1ppt to 120ppt
• Cell Constant: K=10
• Connector: BNC

For more information on calibration, please refer to the Modbus Configuration Utility User Guide.

For information related to probes recommendation and selection criteria, please refer to LDSBus Probe Specifications.

12 Contact Information

Refer to https://brtsys.com/contact-us/ for contact information.

System and equipment manufacturers and designers are responsible to ensure that their systems, and any BRT Systems Pte Ltd (BRTSys) devices incorporated in their systems, meet all applicable safety, regulatory and system-level performance requirements. All application-related information in this document (including application descriptions, suggested BRTSys devices and other materials) is provided for reference only. While BRTSys has taken care to assure it is accurate, this information is subject to customer confirmation, and BRTSys disclaims all liability for system designs and for any applications assistance provided by BRTSys. Use of BRTSys devices in life support and/or safety applications is entirely at the user's risk, and the user agrees to defend, indemnify, and hold harmless BRTSys from any and all damages, claims, suits, or expense resulting from such use. This document is subject to change without notice. No freedom to use patents or other intellectual property rights is implied by the publication of this document. Neither the whole nor any part of the information contained in, or the product described in this document, may be adapted, or reproduced in any material or electronic form without the prior written consent of the copyright holder. BRT Systems Pte Ltd, 1 Tai Seng Avenue, Tower A, #03-01, Singapore 536464. Singapore Registered Company Number: 202220043R.

Appendix A – References

Document References

• Modbus Configuration Utility User Guide
• LDSBus Probe Specifications

Acronyms and Abbreviations

Appendix B – List of Figures and Tables

List of Figures

• Figure 1 - Modbus Salinity Sensor Adapter Hardware Features
• Figure 2 - Modbus Salinity Sensor Adapter - Connection Diagram
• Figure 3 - RS485-RJ11 Cable(30cm)
• Figure 4 - Modbus Salinity Sensor Adapter Flush Mount
• Figure 5 - Modbus Salinity Sensor Adapter DIN Rail Mount
• Figure 6 - Modbus Salinity Sensor Adapter Dimension – Top View
• Figure 7 - Modbus Salinity Sensor Adapter Dimension – Side View
• Figure 8 - Modbus Salinity Sensor Adapter Dimension – Bottom View

List of Tables

• Table 1 - Part Numbers / Ordering Information
• Table 2 - Modbus Salinity Sensor Adapter Specifications
• Table 3 - Modbus Salinity Sensor Adapter Hardware Features
• Table 4 - RS485-RJ11 Cable(30cm) Pin Configuration
• Table 5 - Modbus Registers
• Table 6 - System Status LED Indicators

Appendix C – Revision History

Document Title: Modbus Salinity Sensor Adapter Datasheet

Document Reference No.: BRTSYS_000187

Clearance No.: BRTSYS#108

Product Page: https://brtsys.com/product-category/adapters/

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