Data Logger / Comm Stick Reference Design
An illustrative reference design for data loggers / comm sticks in the PV & ESS management and communication layer: polls inverter, meter and combiner box data over isolated RS-485 and uploads to the O&M cloud (MQTT / HTTPS) over Ethernet, 4G or Wi-Fi depending on the site; 12 V comes from the inverter's communication port or an adapter. As the most common communication node in a plant, its port protection and isolation are designed for long outdoor cable runs. Each position is marked with the VOOHU parts available, recommended part numbers and package pinouts.
Illustrative PCB ⇄ Schematic
Illustrative top-side view arranged by functional zone (not the actual layout). Red numbered dots mark positions VOOHU can supply. Click a component on the board, an entry in the index below or a part in the schematic to see recommended parts and package pinouts on the right.
Illustrative RS-485 topology: the MCU UART is converted to a differential signal by isolated transceiver U2, then passes the stage-2 clamp ESD D1 (WHALD30E2B), the signal-line common-mode choke L1 (WHAC-4532A-510U0) and the stage-1 three-pole gas discharge tube GDT1 (WHGT090V1P0A, center electrode to chassis ground) to terminal J1; the transceiver's isolated side is powered by the push-pull isolated supply. Termination / bias resistors depend on bus length and node count; only their symbols are drawn, without values.
Board bill of materials
Summarized by position; click any row to locate it on the board above.
| No. | Zone | Position | Ref. | VOOHU category | Recommended part | Availability |
|---|---|---|---|---|---|---|
| 01 | A RS-485 data acquisition | RS-485 terminal (inverter / meter) | J1 | — | — | Non-VOOHU |
| 02 | A RS-485 data acquisition | RS-485 GDT | GDT1 | GDT | WHGT090V1P0A | VOOHU |
| 03 | A RS-485 data acquisition | RS-485 CMC | L1 | Signal Line Common Mode Chokes | WHAC-4532A-510U0 | VOOHU |
| 04 | A RS-485 data acquisition | RS-485 ESD / TVS | D1 | TVS ESD | WHALD30E2B | VOOHU |
| 05 | A RS-485 data acquisition | Isolated RS-485 transceiver | U2 | — | — | Non-VOOHU |
| 06 | A RS-485 data acquisition | Push-pull driver + rectifier / LDO | U3 | — | — | Non-VOOHU |
| 07 | A RS-485 data acquisition | Push-pull isolation transformer | T1 | Push-Pull Transformers | WHST06Q02E0 | VOOHU |
| 08 | B Ethernet uplink | RJ45 port (router / switch) | J2 | RJ45 Connector | WH56A31882021103 | VOOHU |
| 09 | B Ethernet uplink | Eth uplink GDT | GDT2 | GDT | WHGD090V1P0B | VOOHU |
| 10 | B Ethernet uplink | 10/100 LAN transformer (high isolation) | T2 | LAN Transformers | WHSH16F01D4 | VOOHU |
| 11 | B Ethernet uplink | Eth uplink ESD | D2 | TVS ESD | WHALD03G4U | VOOHU |
| 12 | B Ethernet uplink | 10/100 PHY | U4 | Ethernet PHY | JL1101BR-NI | VOOHU |
| 13 | C 4G / Wi-Fi uplink | Nano SIM card socket | J3 | SIM Card Sockets | WHNS135-T1151-01 | VOOHU |
| 14 | C 4G / Wi-Fi uplink | SIM card ESD array | D3 | TVS ESD | WHTA5V01P2C | VOOHU |
| 15 | C 4G / Wi-Fi uplink | 4G Cat.1 module | U5 | — | — | Non-VOOHU |
| 16 | C 4G / Wi-Fi uplink | Wi-Fi antenna connector | J5 | — | — | Non-VOOHU |
| 17 | C 4G / Wi-Fi uplink | Wi-Fi module | U6 | — | — | Non-VOOHU |
| 18 | D Control core | MCU (acquisition + protocol conversion) | U1 | — | — | Non-VOOHU |
| 19 | E 12 V power | 12 V power (inverter COM port / adapter) | J4 | — | — | Non-VOOHU |
| 20 | E 12 V power | Bidirectional input TVS | D4 | TVS ESD | WHTB058VA | VOOHU |
| 21 | E 12 V power | Input power-line common-mode choke | L2 | Power Line Common Mode Chokes | WHAL-7060A-102T0 | VOOHU |
| 22 | E 12 V power | Buck converter (12 V → 4G 3.8 V) | U7 | — | — | Non-VOOHU |
| 23 | E 12 V power | Buck converter (5 V → 3.3 V / core) | U8 | — | — | Non-VOOHU |
| 24 | E 12 V power | Molded inductors ×2 (DC-DC) | L3 L4 | Molded Inductors | WHYT0630 Series | VOOHU |
Resources & downloads
Board bill of materials
Reference designators, zones, VOOHU categories, recommended parts and availability for all 24 positions. Opens directly in Excel.
Datasheet collection
Datasheet PDFs for the VOOHU parts recommended on this board.
Design files & footprint library
Schematic, PCB, and VOOHU part footprints and 3D models.
Coming soonRequest the data logger / comm stick reference design full package
Includes the full-board position list, datasheets for the recommended VOOHU parts and position-by-position selection notes. For selection advice tailored to your uplink (Ethernet / 4G / Wi-Fi), number of connected devices or enclosure type, please include it in your requirements. We reply within 24 hours on working days.
