Modbus Power Meters

Modbus is a data communication protocol commonly used in a variety of industrial electronic applications, including power and energy monitoring.

Connecting a Modbus power meter to the Dynalite system enables System Manager to record, display, and report power and energy trends for metered circuits, luminaires, and/or devices.

Modbus over RS-485

Modbus meters are generally connected to the Dynalite network via a DDNG485 network gateway. If required, the RS-485 port on a PDDEG-S, PDEG, or PDEB can also be configured for Modbus instead of DyNet.

The DDNG485 v3, PDDEG-S, PDEG, and PDEB can independently poll the Active Power and Active Energy registers from connected Modbus devices, and report collected metrics to System Manager as required. Modbus polling for other registers, or via the older DDNG485 v2, must be enabled in System Manager Configuration > Site Settings > Polling.

While the Modbus protocol does support daisy-chained networks for multiple devices, we recommend using a star-wired configuration with a dedicated hub (example below) unless otherwise specified by the meter manufacturer. If only using a single meter, you can connect this directly to the appropriate RS-485 port on the gateway.

modbus network hub diagram
To ensure available bandwidth for polling traffic, we recommend a maximum of 30 power meters per network gateway. If exceeding this number, you may need to increase the gateway’s polling interval.

Supported RS-485 Meters

System Builder natively supports the following Modbus meters:

Manufacturer Model

ABB

A41
A42
A43
A44

Circutor

CVM-1D
CVM-C10
CVM-MINI
CVM-NET
CVM-NET4

Electro Industries

DMMS300+

ELNet

LT/GR Legrand - Ecometer

Schneider

BCPMSCA

Socomec

I-30
I-60

If your meter is not listed above, you can add it as a custom user-defined meter.

Modbus over TCP/IP

The PDDEG-S Ethernet gateway can aggregate power and energy data from Modbus over TCP/IP meters on the same LAN. This requires a custom user-defined meter for each make/model, and you will need the IP address and port number for each meter.

This feature is not currently available for the PDEG or PDEB.