The Vaisala Indigo 520 Series transmitter with dual probe and multi-parameter support is a host device for Indigo-compatible, stand-alone Vaisala smart probes. The transmitter provides many additional functions to the Indigo probes. 

The touchscreen display provides local data visualization and easy access to the probe configuration. The transmitter also extends the options for connectivity, supply voltage and cabling compared to using only one smart probe. It also provides mechanical support if wall mounting of a probe is preferred. The robust metal housing with IP66 and NEMA4 protection ensures reliable performance even under the harshest conditions.

Indigo-compatible smart probes include humidity probes (HMP3, HMP4, HMP5, HMP7, HMP8 and HMP9), dew point probes (DMP5, DMP6, DMP7 and DMP8), carbon dioxide probes (GMP251 and GMP252), oil moisture probes (MMP8), temperature probes (TMP1) and vaporized hydrogen peroxide probes (HPP271 and HPP272). The Indigo 520 is also compatible with the MHT410 humidity, hydrogen and temperature transmitter for online monitoring of power transformers.

The Indigo 520 transmitter has space for up to two probes at the same time. The plug-and-play probes are easy to install and remove for calibration.

- Universal transmitter for Indigo-compatible Vaisala probes
- Supports two probes simultaneously
- Touchscreen display
- Rugged metal housing with IP66 and NEMA4 protection
- Four configurable analog outputs
- Two relays
- Ethernet connection with web interface for remote access
- Modbus TCP/IP protocol
- Multiple power supply options, including PoE (Power over Ethernet) and mains power