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  • New item   -29.83€USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET
    New item   -29.83€USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET 1
    New item   -29.83€USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET 2
    New item   -29.83€USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET 3

    USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET

    Code: CNVT-USB-RS485-SET
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  • Product description

    USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET

    CNVT-USB-RS485-SET – Sentera Controls USB to Modbus RTU (RS485) converter with all the necessary connecting cables. On the computer it works as a standard Windows COM port, so Sentera controllers, sensors and modules can be monitored and configured directly from a laptop.

    Key idea:
    This is a service tool for the installer's bag: you arrive at the site, plug the converter into USB, connect to the Modbus line with an RJ45 cable – and see all of the device's registers. The kit already includes both UTP cables and a USB extension, so there is nothing extra to look for.
    Interface
    USB 2.0 (A type) → RS485
    Protocol
    Modbus RTU, 4 800–230 400 b/s
    Power supply
    5 VDC from USB, up to 20 mA
    Scope of delivery
    Converter + USB extension cable + 2 UTP cables

    Operating principle

    The converter is plugged into the computer's USB port (a 0.5 m USB extension cable is included in the kit) and is installed in the system as a standard Windows COM port. The RJ45 socket is connected to a Sentera device or a Modbus RTU (RS485) line: with an RJ45–RJ45 cable to -M and -H type products with a socket, with an RJ45–bare wire cable to terminals A and /B. Only contacts 3–4 (A) and 5–6 (/B) are used in the socket, while 1, 2, 7 and 8 are not connected, so the converter does not power the connected device – it is itself powered from USB (5 VDC, up to 20 mA).

    Communication: 2-wire RS485 bus for up to 256 nodes, speed 4 800–230 400 bps, parity none / even / odd, 7 or 8 data bits, 256 B input and output buffers. Two green LEDs indicate transmit (TX) and receive (RX).

    Result – the device registers are visible and editable in 3SModbus or another Modbus program, and the RS485-side protection (±16 kV ESD per HBM; ±8 kV contact / ±30 kV air discharge per IEC 61000-4-2; ±4 kV EFT per IEC 61000-4-4; ±2.5 kV 1.2/50 µs surge per IEC 61000-4-5) allows safer connection to lines already operating on site.

    Benefits CNVT-USB-RS485-SET?
    One inexpensive tool lets you commission, check and reconfigure any Sentera Modbus RTU device on site – without a BMS and without additional power.

    Technical specifications

    Product type USB–Modbus RTU (RS485) converter with cables (kit)
    Manufacturer / code Sentera Controls / CNVT-USB-RS485-SET
    Power supply 5 VDC via the USB connector, Imax 20 mA
    USB USB 2.0, A type
    RS485 connection RJ45: 3–4 – A, 5–6 – /B; 1, 2, 7, 8 – not connected
    Bus 2-wire RS485, up to 256 nodes
    Sparta 4 800–230 400 bps
    Parity / data bits none, even, odd / 7 or 8
    Buffers 256 B input, 256 B output
    RS485 protection ±16 kV ESD (HBM); ±8 kV contact, ±30 kV air (IEC 61000-4-2); ±4 kV EFT (IEC 61000-4-4); ±2.5 kV 1.2/50 µs (IEC 61000-4-5)
    Indication Green LED1 – transmit (TX), green LED2 – receive (RX)
    Operating system Installed as a standard Windows COM port
    Scope of delivery converter, USB-A cable with a socket (0.5 m), UTP cable with RJ45 plugs at both ends (U502GYXXXRJ8RJ8) and a UTP cable with an RJ45 plug at one end and bare wire ends at the other (U502GYXXXRJ8W05)
    Dimensions 22.5 × 21 × 42.5 mm
    Protection class IP30 (EN 60529)
    Operating environment -10…+60 °C, 5–85 % rH
    Weight 50 g net (kit)
    Compliance LVD 2014/35/EU, WEEE 2012/19/EU, RoHS 2011/65/EU

    Manufacturer documentation

    ✔ Recommended by Elektrotechnikos sprendimai

    Original manufacturer documentation – technical data, wiring diagrams and installation instructions.

    Main functions

    • Virtual COM port – the computer sees the converter as an ordinary serial port – suitable for 3SModbus and other Modbus programs.
    • Power from USB – no additional power supply is needed.
    • Wide choice of baud rate and format – 4 800–230 400 bps, none / even / odd parity, 7 / 8 bits – also communicates with non-Sentera Modbus equipment.
    • TX / RX LED – you can see at a glance whether data is being exchanged with the device.
    • RJ45 socket – connected with the same UTP cable as Sentera PoM devices.
    • Line protection – ESD and overvoltage protection on the RS485 side.
    • Complete cable set – An RJ45–RJ45 cable for -M and -H type products, and an RJ45–wire-end cable for -F, -G and -H type products with terminals, plus a 0.5 m USB extension cable.

    Where is it used?

    • Commissioning and tuning of Sentera controllers, sensors and modules
    • Setting the Modbus address, baud rate and parity before connecting to the BMS
    • Troubleshooting a Modbus RTU line
    • Firmware update and register reading via 3SModbus
    • Laboratories, training, control panel manufacturing
    • Addressing many Sentera devices before commissioning on site
    • Checking a working BMS line and finding address conflicts

    On-demand operation

    For ventilation unit commissioning engineers.
    One kit has cables for devices with an RJ45 socket and for terminal-type Sentera devices – nothing to look for on site.
    For the control panel manufacturer.
    In the workshop, pre-addresses and tests Sentera devices before the panel is shipped.
    For training centers and laboratories.
    A ready-made kit for the workstation: converter, USB extension cable and both UTP cable types.

    Practical application

    If a ventilation unit being commissioned has both an -M type Sentera transmitter with an RJ45 socket and a terminal-connected -G type device, then with the CNVT-USB-RS485-SET you connect both using the kit cables and, via 3SModbus, before connecting to the BMS, set different Modbus addresses and the same baud rate within the 4 800–230 400 b/s range.

    Application guide: how it is used in practice

    CNVT-USB-RS485-SET is always connected between the computer and a Modbus RTU device – only what you connect to differs:

    Site What is connected Result Installer's note
    Sentera device with an RJ45 socket (-M, -H types) UTP cable RJ45–RJ45 → converter RJ45 The device is visible in the 3SModbus program, parameters can be changed The device needs a separate power supply – the converter does not power it via RJ45
    Device with terminals A, /B (-F, -G, -H types) UTP cable RJ45–bare wire ends → terminals A and /B Communication without an RJ45 socket on the device Check the A and /B polarity – if reversed, there will be no communication
    A working BMS Modbus line The converter is connected to line A, /B Line devices can be monitored and address conflicts found The computer must not send requests together with the BMS master controller
    Control panel manufacturing / test bench Converter + PoM-powered device Devices are pre-addressed and tested in the workshop Give each device a unique Modbus address

    How to choose a USB–Modbus converter

    Scope of delivery Recommended model
    Converter only – UTP cables are already on hand CNVT-USB-RS485-V2 (converter)
    Converter + 0.5 m USB extension cable + 2 UTP cables (RJ45–RJ45 and RJ45–wires) CNVT-USB-RS485-SET (kit) ← this model
    Rule: if you have no UTP cables or work with Sentera devices of different types (RJ45 and terminals) – choose CNVT-USB-RS485-SET; if you make the cables yourself – CNVT-USB-RS485-V2 is enough.
    When to choose another solution: for permanent remote monitoring over the internet instead of a computer – Sentera internet gateways DIG-M-2, SIG-M-2, DIGWM or SIGWM (SenteraWeb).

    Pros

    • USB-powered
    • Windows COM port – compatible with common Modbus software
    • Wide choice of baud rate and parity
    • TX / RX indication
    • RS485 protection against ESD and overvoltage
    • Small and lightweight
    • All cables included

    Cons / limitations

    • It does not power the connected device through the RJ45 – the device needs its own power supply
    • Galvanic isolation is not specified in the datasheet
    • IP30 – indoors and for use with a computer only
    • Intended for configuration and diagnostics; for permanent remote monitoring – the DIG-M-2 or DIGWM internet gateway

    Safety and installation notes

    • When connecting to live equipment, follow the site's electrical safety requirements; connection to the terminals is to be made by a qualified specialist.
    • When connecting the RJ45-to-wire cable, check the A and /B polarity.
    • Use in an environment of -10…+60 °C and 5–85 % rH.
    • A single Modbus segment must not have two master devices at the same time.

    Quick selection guide

    USB 2.0
    Modbus RTU
    RS485
    RJ45
    IP30
    Kit with cables
    Suitable when you need:
    • to commission and tune Sentera Modbus RTU devices from a computer;
    • to set the Modbus address and communication parameters;
    • to diagnose RS485 line communication problems.
    Check before use:
    • whether the device has an RJ45 socket or terminals A, /B – the cable depends on it;
    • whether the device has its own power supply;
    • whether the PC has Windows and a free USB-A port.
    Important reminder: CNVT-USB-RS485-SET is a configuration and diagnostic tool – for permanent remote monitoring use a Sentera internet gateway.

    FAQ

    Does the transmitter power the connected device?
    No, RJ45 contacts 1, 2, 7 and 8 are not connected, so the device needs its own power supply.
    Which software should I use?
    Compatible with Sentera 3SModbus or any Modbus RTU software running through a Windows COM port.
    How many devices can be seen on one line?
    The RS485 bus supports up to 256 nodes, and each device must have a unique Modbus address.
    What cables are included in the set?
    The kit includes a 0.5 m USB extension cable, a UTP cable with RJ45 on both ends and a UTP cable with RJ45 on one end and bare wire ends on the other.
    What is the difference between V2 and SET?
    The converter is the same, but the SET kit additionally includes a USB extension cable and two UTP cables.
    Which communication parameters can be set?
    The speed is selected within 4 800–230 400 bps, parity none, even or odd, data bits – 7 or 8.

    USB–Modbus RTU (RS485) converter kit with cables | USB 2.0 | RJ45 | 5VDC via USB | IP30 | Sentera Controls | CNVT-USB-RS485-SET

    Sentera CNVT-USB-RS485-SET – a USB to Modbus RTU (RS485) converter with cables for configuring and diagnosing Sentera devices: Windows COM port, 4 800–230 400 b/s, RJ45, USB-powered, IP30.

    Illustrative image may have been created using AI. The appearance of the product may differ slightly from the image shown. Please refer to the technical specification.

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