The first expansion module, the PM1, with a pH or ORP, temperature, and 6 digital inputs. The PM1 features are:

Monitor/Control pH or ORP, and temperature.

6 digital inputs for float switches, water on floor sensors, pressure sensors, etc

Full datalogging support in Apex Base module.

Up to 240 AquaBus modules can be added to the Apex system.

Plug and Play. Automatically recognized when installed into the system.

Two AquaBus connectors for flexible expansion via AquaBus

Led Status Indicator

Upgradeable firmware.

Compatible with Apex and Apex Lite systems.

Galvanic Isolation for accurate and reliable probe readings.

Comes with 3' AquaBus cable.