Data Transmission Unit

The TD-DTU series is positioned as “data acquisition + remote transmission” equipment. The TD-DTU-PRO page states support for multi-band 2G/4G, network adaptation for global regions, and optional GNSS; the TD-DTU-PLUS page states that it uses 4G Cat-1, supports 2G + 4G, and offers optional GNSS. Both representative models list 4G/Bluetooth. Local Bluetooth is suitable for nearby debugging or supporting communication, while the cellular network handles remote backhaul. 1. Cellular network: Confirm the country, carrier, frequency bands, SIM card, APN, and network sunset plan. “Global applicability” should not be interpreted as meaning that no module selection or frequency-band verification is required. 2. Remote transmission modes: The specifications confirm TCP Client, UDP Client, and MQTT Client, with support for TCP/UDP/MQTT and SSL. Platform address, port, certificate, and authentication parameters must be configured consistently for the project. 3. Power supply: PRO is rated for DC 9–36 V; PLUS is rated for DC 9–36 V and includes a 27,000 mAh built-in battery. PLUS is intended for acquisition/remote-transmission applications without an external power source. Actual battery life depends on acquisition frequency, network coverage, temperature, load, and battery condition. 4. Positioning: GNSS is listed as optional in the representative model specifications. When ordering, clearly specify whether positioning capabilities such as GPS/GLONASS/BDS/Galileo/QZSS are required.

Representative models provide 1×RS232 and 1×RS485, and the detail pages state that both can operate simultaneously, with a baud-rate range of 300–115200 bps. This interface combination covers various serial electricity meters, data collectors, controllers, and sensors. If the meter communicates through an optical interface, it can be paired with a standards-compliant TP series optical probe or another project-specific adaptation solution. 1. RS485: Suitable for multipoint bus devices. Confirm A/B/G wiring, termination resistance, bus length, address planning, and isolation/grounding requirements. 2. RS232: Suitable for point-to-point devices. Confirm DB9 or terminal wiring, TX/RX, ground, signal levels, and cable length. 3. SIM/antennas: Representative models list an external Mini SIM slot, one 4G antenna, and one Bluetooth antenna. Actual antenna position, cable length, and waterproof cable routing must be coordinated with cabinet design. 4. Auxiliary interfaces: The pages list a power socket, reset hole, and status indicators to facilitate on-site power-up, network connection, and communication troubleshooting.

The TD-DTU is designed to perform serial data acquisition, cellular remote transmission, and device-level reliability in relatively compact hardware. For automatic meter reading or remote data-acquisition projects, its selection value can be explained to customers from the following six perspectives. 1. Wide-voltage power supply: Representative models support DC 9–36 V, suitable for common DC control-power environments. 2. Cellular remote transmission: 2G/4G or 4G Cat-1 models enable remote data upload, with frequency bands/modules selected according to the target country. 3. Dual serial access: RS232 and RS485 can operate simultaneously, making it convenient to connect meters or devices from different generations in parallel. 4. Platform protocol compatibility: Support for TCP, UDP, MQTT, and SSL provides a foundation for connecting to private servers, industry platforms, or cloud messaging platforms. 5. Off-grid capability: The TD-DTU-PLUS built-in 27,000 mAh battery is suitable for remote points without a stable external power supply; battery life must be calculated based on the actual workload. 6. Industrial reliability: Representative specification pages list -40°C to +75°C, 5%–95% non-condensing humidity, reverse-polarity, overvoltage/overcurrent, lightning, and surge protection, suitable for installation inside cabinets or protected outdoor equipment enclosures.

TD-DTU is particularly suitable for distributed projects where the data volume is relatively manageable, field devices mainly use serial interfaces, and low-maintenance-cost cellular backhaul is required. The following six scenarios can be used as standardized customer-facing descriptions. 1. Automatic meter reading (AMR): Connect electricity, water, gas, or heat meters and transmit the collected data to billing, energy-management, or O&M systems. 2. Power distribution and electrical monitoring: Install in distribution cabinets/enclosures to collect voltage, current, power factor, and other parameters and report abnormalities. 3. Rural and off-grid scenarios: Use the built-in battery capability of TD-DTU-PLUS for remote villages, farmland, water-conservancy sites, or temporary projects; solar/external power supply and battery life should be evaluated. 4. Environmental and water monitoring: Connect water-quality, flow, liquid-level, weather, or environmental sensors for scheduled acquisition and remote reporting. 5. Remote equipment alarms: Upload status data from pump stations, equipment rooms, cold-chain systems, storage tanks, and similar equipment to the backend, where the platform can generate alarms and work orders. 6. Connectivity retrofit for legacy equipment: Add cellular communication to existing meters and controllers that have RS232/RS485 interfaces but lack network connectivity.

Representative specifications explicitly list TCP, UDP, MQTT, and the corresponding TCP Client, UDP Client, and MQTT Client operating modes, with SSL support. These functions address communication and data forwarding from serial devices to remote systems. Whether meter-side protocols such as DLMS, IEC 62056, DL/T 645, or vendor-specific protocols can be read directly depends on the device protocol, configuration capabilities, optical-probe/serial interface, and platform parsing solution, and must be validated during the sample stage. 1. Provide sales/technical support with: remote server address, port, protocol type, authentication method, certificate, message format, heartbeat requirements, and reconnection requirements. 2. Confirm on the device side: serial parameters, meter address, communication password, protocol version, data points, acquisition cycle, exception-retry strategy, and clock requirements. 3. If MQTT is used, define the Topic, QoS, Client ID, authentication, offline caching, and duplicate-message handling rules. 4. If multi-protocol parsing, bulk point-list management, complex edge logic, or multi-Ethernet-port deployment is required, it is recommended to evaluate a TG series gateway at the same time.

TD-DTU product pages provide inquiry options and specification downloads, but no uniform published warranty period or public pricing for all models was found. Therefore, it is recommended to state in after-sales and purchasing FAQs that “standard warranty, extended warranty, pricing, lead time, and customization scope are subject to the written sales quotation/contract,” and to fully verify the network, power supply, battery life, and device protocols before the project. 1. Warranty: Ask about the standard warranty and optional commercial packages for 2–5-year extended warranties, spare units, remote configuration, and on-site support; contract terms prevail. 2. Pricing: Small-quantity samples can be viewed in the Tespro Online Shop. Volume/project pricing, built-in batteries, GNSS, specific modules, or customized services should be obtained through sales@tespro.com. 3. Sample testing: At minimum, verify SIM network access, weak-signal reconnection, continuous serial reading, SSL/MQTT reporting, power-supply fluctuations, PLUS battery life, and data recovery after network interruption. 4. Contact information: sales@tespro.com; info@tespro.com; telephone/WhatsApp +852 4609 4648 and +1-213 610 4797. 5. Brand content channels: The official website also lists six official social-media channels—Facebook, LinkedIn, YouTube, TikTok, X, and Instagram—for viewing public cases and product demonstrations.