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Modbus RTU

Remote Terminal Unit

Physical Layer: Uses serial connection RS-485

Architecture: Master/Slave (or Client/Server), where one master device polls multiple slave devices for data

Daisy-Chain Wiring: Multiple Chiltrix heat pumps can be monitored or controlled via a single interface

Error Checking: Uses Cyclic Redundancy Check (CRC) for reliable data integrity

Message Structure: Includes Slave ID, Function Code, Data, and CRC checksum

Modbus RTU is compatible with various BACNET gateways

Product Description

Chiltrix uses an industry standard Modbus RTU implementation and we can make various registers, addressing, and standard configuration information available as needed. Note, Chiltrix does not support Modbus programming or training, it's available for experienced Modbus users only.

The Chiltrix heat pumps use MODBUS and make a connection available for external controls access. This is an RS485 connection that allows a customer-provided controller (based on Arduino, Raspberry Pi, or other) to monitor and control various aspects of operating the heat pump. It can also connect to various BACNET gateway devices.

Modbus RTU excels in applications needing robust communication between devices in forming the backbone of many legacy and modern industrial networks. Modbus is native to the Chiltrix heat pump and is also used for internal control.

Use Modbus to remotely monitor, log, or in many cases, adjust, various parameters. Below are some examples:

Mode: Heating, cooling, off
Leaving water temperature
Entering water temperature
Temperature target
Flow rate
Power consumption
Calculate Btu/h
Calculate COP
Compressor speed
Fan speed
Pump speed
DHW: On/off/temperature, target temperature
Error codes

There are >200 potential parameters for monitoring or control. Please let us know what you need.