K-Detect-iON

1. Introduction

The K-Detect-iON sensor is an advanced, self-calibrating standalone device specifically designed to monitor flammable gas types in stationary systems. With a user-settable Slave ID offering 254 combinations and factory calibration, this sensor provides enhanced convenience and reliability. With a recommendation of one sensor per rack for comprehensive monitoring, the K-Detect-iON sensor is an indispensable tool for critical facilities. The sensor can be configured to detect different gases based on specific customer needs. It is listed to UL2075 and is a calibration-free flammable gas sensor designed to detect the presence and measure the concentration of flammable gases in non-hazardous critical facilities from 0-100% LEL. Patent Pending.

2. All about K-Detect-iON

2.1 Certifications and Calibrations

• ETL listed to UL 2075
• IEC60068-2-30, IEC 60068-2-6, IEC 61000-4-4, IEC 61000-4-5, IEC 61000-4-6
• Compliant with EMC directive (EU) 2014/30 - EN50270:2015, EN55032:2015, EN55035:2017
• Compliant with Low Voltage Directive (EU) 2014/35 - EN61010:2010
• REACH compliant
• RoHS 3 compliant

2.2 Sensor Metrics

2.3 Technical Specification

2.4 Environmental Specification

• Hydrogen (H2)
  Operating temperature range: -40°C to 75°C (-40°F to 167°F)
  Humidity (operating and storage): 0 to 100% RH (non-condensing)
• Methane (CH4)
  Operating temperature range: -40°C to 70°C (-40°F to 158°F)
  Humidity (operating and storage): < 90% RH (non-condensing)

2.5 Physical Specifications

The K-Detect-iON sensor features a steel enclosure for industrial grade use. It offers flexible mounting options including OU rack, DIN rail, or wall mountable configurations. The dimensions are 71mm (2.79") x 70.5mm (2.77”) x 30 mm (1.18"), and it weighs 193g (0.43lb).

2.6 Parts of the K-Detect-iON Sensor

• RJ45 Port: Used for communication with the Base Unit (currently not used).
• LED Status Light: Indicates operational status.
  • Warning: Amber
  • Down: Red
  • Fault: Red
  • Normal Condition: Green
• Gas Cap: A protective cover for the sensor, ensuring durability and protection from external elements.
• Configurable output relays:
  • A: Relay A - Alarm
  • C: Relay C - Fault
  • B: Relay B - Alarm
• Mounting hole: Allows for flexible installation according to user preferences. Refer to section 6.2 for mounting options.

Terminal Block: This block comprises terminals for various connections:

• Terminal 1: 12 to 24V DC power input
• Terminal 2: (B-) Connection
• Terminal 3: (A+) Connection
• Terminal 4: Ground (GND)

Rotary Encoder: A user interface component that can be rotated to input or adjust settings, facilitating user interactions with the sensor's configuration. It supports user-settable addresses out of 254 combinations.

3. System Architecture

The K-Detect-iON sensor is the core of the system architecture, operating on a direct power supply ranging from 12 to 24V DC. It is designed for monitoring gas levels and interfaces directly with an INDUSTRIAL CONTROLLER (ICS) or Modbus Controller, enabling efficient control and monitoring within industrial environments. The sensor features three normally open relays, providing additional control capabilities and allowing the system to actuate external devices or processes.

4. CH4 Gas Detection: Cross Sensitivity and Precautionary Measures

Cross-sensitivity occurs when a gas sensor responds to gases other than its target gas. This is important in environments with multiple gases. Careful management is required for accurate detection and system reliability. Gas contaminants can also affect sensor performance and longevity.

Gas Contaminants to Consider:

• H2S (Hydrogen Sulphide)
• SOx (Sulphur Oxides)
• Cl2 (Chlorine)
• HCl (Hydrogen Chloride)

Gases Cross-Sensitive to Methane (CH4):

• Methane (CH4)
• Hydrogen (H2)
• Carbon Monoxide (CO)
• Propane (C3H8)
• Ethylene (C2H4)
• Ethane (C2H6)
• Hexane (C6H14)
• Benzene (C6H6)
• Toluene (C7H8)
• Xylene (C6H4)
• Ammonia (NH3)
• Hydrogen Sulphide (H2S)
• Acetaldehyde (C2H4O)
• Formaldehyde (CH2O)
• R-22
• R-134a
• R-404A
• R-410A

Precautions for Effective Operation:

1. Exposure to silicone vapours: Silicone vapours can coat the sensor's surface, irreversibly inhibiting sensitivity. Avoid areas with silicone adhesives, hair grooming materials, or silicone rubber/putty.
2. Highly corrosive environment: High density exposure to corrosive materials can affect the sensor.
3. Contamination by alkaline metals: Contamination by alkaline metals, especially salt water spray, may cause sensor drift.
4. Operation in zero/low oxygen environment: Sensors require approximately 21% ambient oxygen to function properly. They cannot operate in a zero or low oxygen atmosphere.
5. Excessive exposure to alcohol: High concentrations of alcohol (e.g., 10,000 ppm or more) for extended periods can saturate the sensor's filter.
6. Lighter gas exposure test: This sensor's filter blocks iso-butane (a common lighter gas component), making this test unsuitable for verifying its sensing capabilities.

5. H2 and Other Flammable Gas Detection

Hydrogen (H2) and other flammable gases pose significant safety risks in industrial and commercial settings. Reliable detection systems provide early warnings and ensure safety compliance. The K-Detect-iON sensor is inherently immune to siloxanes and poisoning.

Flammable Gases and Accuracies:

6. Implementation

This section provides practical guidance on deploying the K-Detect-iON sensor technology, covering installation, integration, testing, and commissioning processes. It aims to prepare users for effective sensor deployment.

6.1 Preparation

Before installation, ensure all essential materials and devices are readily available:

• Devices Needed: K-Detect-iON sensor
• Tools Needed: Modbus cables, Screwdriver, Screws, bolts and nuts for mounting.
• Things to check: Ensure no visible damage on devices, verify network cable functionality, and prepare the installation location.

Adhering to these guidelines will contribute to a successful and trouble-free installation process.

6.2 Mounting Installation Guidelines

The sensors offer flexible mounting solutions:

Important Note: For safety and functionality, the unit must be grounded to an earth ground. Connect the grounding wire to an enclosure mounting hole using a screw and washer for a reliable connection. Proper grounding is essential for Electrostatic Discharge (ESD) protection and optimal performance. Ensure compliance with local electrical and safety codes.

• DIN Rail: Ideal for secure, space-efficient mounting with compatible enclosures or control panels.
• 0U Rack: Allows for efficient and organized rack-based installation, conserving valuable rack space.
• Wall Mount: Perfect for affixing units to walls, optimizing placement within your environment.
• Magnetic: Offers the convenience of magnetic attachment, making it easy to position components as needed.

7. Setting Up

7.1 Securing Wires in Screwless Terminal Blocks

1. Push and hold the orange tab: Use a finger or a precision flat screwdriver to push the orange tab towards the terminal. This action opens the contact, creating space for the wire.
2. Insert the wire: While holding the orange tab, fully insert the stripped end of the wire into the terminal block. Ensure the wire is properly stripped and aligned. Use a solid wire with a gauge ranging from 16 to 24 AWG for optimal compatibility.
3. Release the tab: The spring will secure the wire in place, ensuring a firm connection.
4. Gently tug the wire: Confirm that the wire is securely held within the terminal block.

7.2 Powering up the K-Detect-iON

The K-Detect-iON sensor can be powered via a direct current (DC) source, accommodating voltages from 12 to 24 volts. This ensures compatibility with common industrial DC power systems.

Terminal Block Connections:

• Terminal 1: 12 to 24V DC power input
• Terminal 4: Ground (GND)

Note: Refer to section 7.1 for detailed instructions on inserting wires into the terminal block.

Important Note: The device requires a minimum warm-up period of 2 days in a clean environment to ensure accurate readings. After the warm-up period, perform a power cycle to ensure optimal operation.

7.3 Standalone RS485 Connection (Modbus)

Below is the wiring configuration for the terminal block used to connect the sensor to your platform via RS485:

Terminal Block:

• Terminal 1: 12 to 24V DC power input
• Terminal 2: (B-) Connection
• Terminal 3: (A+) Connection
• Terminal 4: Ground (GND)

Note: Refer to section 7.1 for instructions on inserting wires into the terminal block.

Setting the Slave ID Address: Refer to the rotary encoder image. A pointer indicates the set value. The Slave ID is set to hexadecimal. For example, setting the rotary encoder to '1' and '2' results in a Slave ID of '12'.

Important Note: Combinations of 0 and 0, or F and F are not functional. Ensure these are avoided.

7.3.1 Default Modbus Connection Settings

7.3.2 Default Relay Threshold

Relays are triggered based on the flammable gas reading, expressed as a percentage of Lower Explosive Limit (%LEL). By default:

• Relay A and B thresholds are set for CH4.
• Relay C is set as the Fault relay.

Note: Sensor type and threshold values can be customized using the Modbus table in Section 7.4.

7.3.3 Default Relay State

The default relay state refers to its initial position when no external power or signal is applied (Normally Open or Normally Closed).

A power cycle is required after applying changes.

7.3.4 Relay Delay

Relay delay is the intentional time interval between the activation signal and the actual switching action of the relay.

7.3.5 Relay Minimum Running Time

This defines the minimum duration a relay remains active after being triggered.

7.4 Modbus Table

The Modbus table details the registers for sensor data and configuration:

NOTE: To apply changes to Modbus connection settings, refer to the provided register addresses (40002, 40003, 40004, 4007, 4008, and 40023). A reboot is required if changes are made to Parity, Baud Rate, or Relay Default State. The 40041 register shows relay status using a bitwise system: Relay 1=1, Relay 2=2, Relay 3=4. Energized relays add their values to the total displayed.

7.5 Connecting K-Detect-iON to Fire Alarm

To connect the K-Detect-iON sensor to two fire alarm wires in a terminal block for a series connection, follow these crimping steps:

1. Prepare the wires: Strip insulation from the ends of the fire alarm wires to expose copper conductors. Ensure both wires have the same stripped length for a secure connection.
2. Insert into the Ferrule: Take a 16-24 AWG ferrule connector and insert both stripped wire ends. Ensure wires are fully inserted and aligned within the ferrule.
3. Crimp the Ferrule: Place the ferrule into the crimping tool, align it in the correct slot, and squeeze firmly to secure the connection. The ferrule should hold both wires tightly.
4. Verify the Crimped Connection: Check the crimped ferrule for a secure and solid connection; wires should not be loose or able to slip out.
5. Connect to the Terminal Block: Insert the crimped ferrule into the designated terminal block for the K-Detect-iON sensor. Refer to Section 7.1 for detailed instructions on securing the ferrule.

8. Testing

8.1 Periodic Bump Testing of Sensors

Periodic bump testing confirms proper operation and integration with safety systems. It is recommended at least annually, or during initial system setup. For gas calibration, Calgas cylinders and a 2.5 LPM regulator are typically used.

Required equipment: Gas sensor, Gas Bump Adapter (AX-GAS-BUMP), Gas tubing, Gas valve regulator (300ml/min), Gas cannister.

Procedure:

1. Prepare Workspace: Ensure proper ventilation.
2. Prepare the sensor: Remove the gas cap by rotating counter-clockwise and replace it with the gas bump adapter, rotating clockwise until secure.
3. Connect tubing: Connect one end of the gas tubing to the adapter and the other end to the gas cannister. Connect the gas sensor to the controller and wait for warm-up.
4. Secure Gas Cylinder: Ensure the gas cylinder is securely mounted and stable.
5. Perform the Bump Test: Gradually open the cylinder valve for controlled gas flow (do not fully open). Let gas flow until the sensor detects it. Monitor sensor readings.
6. Stop Gas Flow: Close the cylinder valve.
7. Verify the Sensor Response: Check that sensor readings respond to gas exposure and trigger alerts if configured. Refer to Section 8.4 for Modbus testing.
8. Maintenance: If the sensor passes the bump test, consider it operational. Note any errors or values from the status register before contacting the manufacturer if issues arise.

8.2 Bump & Calibration gases for CH4

Use synthetic air with approximately 20% VOL oxygen, simulating natural environments. Preheat the sensor for at least 2 days before testing. Maintain a low flow rate. CH4 Gas Cylinder: 50% LEL - 17L steel (Compatible with 6000 Series Multiflow). See: https://www.calgas.co/biosystems-54-9079-equivalent

Note: Results may differ when using target gas mixed with other gases.

8.3 Bump & Calibration gases for H2 & other flammable gas detection

Use zero air or recommended gas mixtures for consistent background gas. Suggested flow rate for the gas valve regulator is 300 mL/min.

H2 Gas Cylinder: 50% LEL - 34L steel (Compatible with 6000 Series Multiflow). See: https://www.calgas.co/50lel-hydrogen-341

Note: Results may differ when using target gas mixed with other gases.

8.4 Testing via Modbus

Regular assessment of gas sensor performance via Modbus communication is crucial for system dependability and functionality. This involves using Modbus commands to read or write data from device registers.

General Guide for Modbus Testing:

Requirements:

• Modbus Master Device or Software (e.g., Modbus Poll, QMod Master)
• K-Detect-iON sensor

Procedure:

1. Identify device registers: Consult the Modbus Table (Section 7.4) to find specific registers for reading or writing data (e.g., sensor reading, status).
2. Confirm Modbus device address: Ensure you know the unique address of the device on the Modbus network.
3. Check communication settings: Refer to sections 7.3.1 to 7.4 for settings like baud rate, stop bits, and parity. Configure your Modbus master software with these same settings.
4. Connect the Modbus Master: Physically connect your Modbus master (computer or controller) to the sensor via the terminal block (Terminal 2: (B-) Connection, Terminal 3: (A+) Connection). Refer to Section 7.1 for wire insertion guidance.
5. Launch Modbus master software: Create a new connection to the sensor.
6. Configure Connection: Enter communication parameters and set a unique slave ID using the rotary encoder. Enter this ID into your Modbus Master configuration. Note: Slave ID is hexadecimal. Identify the Modbus register address (e.g., 30002 for VOC sensor), enter it with quantity and scan rate. Input the correct data type for accurate real-time values.
7. Identify Relay Register: Determine the Modbus register address for the relay you wish to trigger (e.g., 40007 for Relay A). Check if it's a discrete input, coil, or holding register.
8. Write the Modbus Command: In the Modbus master software, find the function code for writing to a discrete output. Enter the Modbus Slave ID, register address, and the command value to trigger the relay.
9. Send Modbus Command: Trigger the relay by sending the command from the Modbus Master to the Slave device. Monitor the response to ensure successful triggering.
10. Verify the Relay State: Check the physical state of the relay on the Modbus Slave device.
11. Triggering Relay using gas bump test: Identify the sensor value to test (e.g., H2). Assign it to a relay (e.g., H2 to Relay A threshold). Set the threshold value in Modbus address 40005 (e.g., 10% LEL for H2). Apply gas to the sensor and observe if the H2 value increases past the threshold, triggering Relay A.