Lovato DMED301 Three-Phase Energy Meter 80 A with RS485

Lovato DMED301 three-phase energy meter, 80 A, RS485

The Lovato DMED301 is a four-module three-phase plus neutral energy meter with direct connection up to 80 A and an RS485 serial interface. It measures active energy to class 1 and reactive energy to class 2. Seven Star LLC supplies the DMED301 in Oman and the GCC as an independent supplier in Muscat.

The designation is the catalogue type itself. The catalogue lists the DMED100T1 as the single-phase meter and the DMED301 as the three-phase meter with the RS485 port. Compare it with the DMED300T2, which has pulse output only, and with the DMED100T1 for single-phase circuits.

DMED301 technical specifications

What the RS485 port adds to the DMED301

With the serial port the meter becomes a data source for a building management system, an energy gateway or a SCADA. Baud rate is selectable from 1200 to 38400 bps, so a long chain of meters can run on a single RS485 line. This removes the manual reading of registers and allows demand, trends and cost allocation to be calculated in software.

Both active and reactive energy are measured, so the data show not only consumption but also the reactive component that affects the power factor. Reactive accuracy of class 2 is enough for monitoring and for deciding whether capacitor banks are needed.

Connecting the DMED301 to the circuit

Because of the direct connection up to 80 A, no current transformers are used. The 25 mm² terminals suit heavy cable. For loads above 80 A a meter intended for current transformers is needed, and our team can suggest a suitable catalogue part. The data sheet gives a maximum consumption of 20 VA and 1.35 W.

DMED301 selection checklist

• Three-phase four-wire network of 400/230 V
• Maximum load current under 80 A
• RS485 interface needed for remote reading
• Protocol and addressing of the monitoring system
• Active and reactive energy data requirement
• Four DIN modules of space
• Certified billing use, to be confirmed separately

Installing and commissioning the DMED301

Mount on the rail, wire the voltage and current terminals according to the diagram and tighten to 2 Nm. Protect the circuit upstream with a breaker sized for the cable. Set communication address and baud rate and check that the master reads the meter.

Compare the first day of consumption with the expected profile. An unexpectedly low value may indicate a swapped phase wiring or a missing neutral, both of which are easy to correct at commissioning.

Typical DMED301 applications in Oman and the GCC

Use it for sub-metering of floors, chillers, workshops and camps. In the Gulf, cooling dominates consumption, so a meter on each chiller circuit gives valuable data for efficiency work. Place it in a ventilated board, as the temperature limit is +55 °C.

DMED meters compared

When planning an RS485 network, remember that every meter needs a unique address, that the bus needs correct termination at both ends and that cable screens should be grounded at one point. A line of ten or twenty meters can run on one pair if the baud rate is chosen to match cable length. If readings drop out, check polarity and termination before suspecting the meter. It is good practice to read the total energy register into the monitoring system at fixed intervals, so that a communication failure does not lose the consumption history.

Think also about the physical side of the installation. With a weight of 360 g and four DIN modules, the meter is light but its terminals take cable up to 25 mm², so cable stiffness can pull on the device if the cables are not supported. Fasten the conductors close to the terminals with a rail-mounted clamp and keep the voltage sense wiring short. The operating temperature limit of +55 °C is easily reached in an unventilated board in summer, so install the meter at the lower part of the board where air is cooler and keep it away from heat sources such as soft starters or power supplies.

Information to send with an RFQ for the DMED301

• Part number DMED301 and quantity
• Network voltage and maximum current
• Communication system and protocol
• Billing certification needs
• Delivery location
• Project reference

Site conditions in Oman for the DMED301

Electrical rooms and outdoor panels in the Gulf often operate well above the 25 °C reference temperature used in many catalogues. Before you finalise the DMED301, compare the expected panel temperature with the operating range and any output derating stated in the manufacturer documentation, and leave the recommended clearance above and below the device for convection. Supply quality also varies between sites, so confirm the input voltage range, frequency and any requirements for protection on the supply side.

Where the device feeds or monitors critical loads, plan how faults will be signalled to the control system and how a replacement can be installed quickly. Keeping one spare DMED301 per site and recording its settings helps maintenance teams in Oman restore service with minimum downtime.

Documents and quotation

Send the part number DMED301 and we will confirm the documents available for it, such as the technical data sheet, wiring diagram and instruction sheet, together with availability and lead time.

Seven Star LLC is an independent supplier in Muscat and is not an official channel of the manufacturer. Share the quantity, delivery location and project reference with the request and we will answer with a formal quotation.