DMU801 houses the plug‑in modules that provide connections to the sensors. To safeguard the system and sensors from external power surges, analog and serial modules (DMA801/DMA802 and DMS801) have internal surge protection.
For Ethernet Switch Module (DME801), Vaisala recommends external surge protection when devices connected to it are located outside the weather station enclosure.
All the printed circuit boards (PCB) in the modules have conformal coating for better humidity resistance.
| Plug-in module type | Purpose |
|---|---|
|
Analog Measurement Modules DMA801 and DMA802 |
Add analog channels and convert the analog data into digital format. |
|
Serial Module DMS801 |
Provide ports for sensors with serial interface. |
| Ethernet Switch Module DME801 | Adds Ethernet connections. |
| Modem Carrier Module DMX801 | Allows connecting a mPCIe card modem to DMU801. |
The number and type of plug‑in modules in the installation depend on the system configuration. Typically, DMU801 is delivered with plug‑in modules installed but the modules are also available as spare parts and can be plugged in later to expand the selection of sensor interfaces. The plug‑in modules have handles for easy installation.
The sensor cables are connected to the plug‑in modules with lockable spring‑cage connectors.