On August 5, 2026, a customer asked LONGWELL for an RS485 version of an EC circular duct fan. The customer already manufactured a controller using Modbus RTU and wanted to command the fan directly, without an additional LONGWELL control box.
Make the control interface explicit
The request covered more than a connector change. It asked for the register map used to set speed and read status, plus the default serial settings and confirmation of configurable node address and baud rate.
LONGWELL’s engineering team prepared the LWDE3G100-IS-01-08 specification, which completed technical review on August 5. The reviewed output identifies RS485 speed control.
Values in the revised specification
| Parameter | Specification value |
|---|---|
| Supply | 110–240 VAC, 50/60 Hz |
| Speed | 2800 rpm |
| Rated input power | ≤27 W |
| Maximum airflow | 385 m³/h |
| Maximum static pressure | 269 Pa |
The airflow and pressure maximums are separate points on the fan characteristic. The register map, serial settings and address plan must be agreed with the customer for its controller. The documented output is the revised fan specification; commissioning on the customer’s bus requires those details to be confirmed together.
Discuss a similar requirement
Send LONGWELL your airflow and pressure duty point, power supply, available installation space, control needs, operating environment and drawings. Contact our engineering team to discuss a suitable fan configuration.
Choose the right duct fan
Longwell manufactures 255 duct fans in-house. Send airflow, static pressure and voltage — an engineer replies with a matching model, performance curve and price within one working day.
