Installation of DDSU 666 electricity meter (single-phase)

This page describes the installation and connection of the single-phase meter DDSU 666. The meter is supplied with the Inverter vision one. However, DO NOT use it in 3-phase networks. Order the three-phase meter DTSU 666 for use in three-phase networks.

ATTENTION

The SOLARWATT Inverter is only compatible with the DDSU and DTSU Solarwatt version (software version). You can only obtain the Solarwatt version of these meters from Solarwatt or Solarwatt partners. You can recognize the Solarwatt version by the Solarwatt logo on the label of the electricity meter packaging (see illustration).

Label electricity meter Solarwatt version

Danger

Risk of electric shock or fire

Before connecting the cables, make sure that the meter is not damaged.
Make sure that the earthing wire is securely installed.
Before switching on the appliance, make sure that the wiring is correct.

Technical data

Dimensions: 100 x 36 x 65.5 mm (2 HP)

Max. Current: one CT terminal can be used for a measuring range of up to 100 A

CT terminal cable length: 6 m (can be cut to size or extended up to 15 m)

Max. Distance to the inverter: 100 m

Installing the meter

Observe all Safety Instructions and requirements for the installer.

The meter is included with the Inverter vision one.

However, DO NOT use it in 3-phase networks. Order the three-phase meter DTSU 666 for use in three-phase grids.

You can find the three-phase meter in the Solarwatt webshop here.

When installing the meter, please refer to the wiring diagrams provided by Solarwatt Wiring diagrams for single-phase and three-phase grids.

Hook the meter onto the top edge of the top-hat rail in the house connection box and press down until it clicks into place

Mounting the meter on the top-hat rail

The voltage is measured via the direct connections of the DDSU 666:

PIN 3 -> N Un
PIN 4 -> L1 U1

Current measurement is always carried out via the CT terminal supplied, which is connected to phase L1 of the domestic installation.
The CT terminal must be positioned in the switch cabinet so that the total current can be measured before transfer to the domestic electricity meter.

A CT terminal can be used for a measuring range of up to 100 A.

Current and voltage measurement DDSU

ATTENTION

Ensure that the current measurement direction of the CT terminal is correct. The arrow on the CT terminal points in the direction of the domestic consumer.

First connect the cable, then close the CT terminal. You must adhere to this sequence so that the CT terminal is not damaged by overvoltage.

DDSU current and voltage measurement - pin assignment

	Pin of the meter	Port/device	Conductor cross section	Outer diameter
direct voltage measurement	3	L1	4 mm² - 25 mm² multi-core outdoor copper cable	5 - 10 mm
	4	N
Current measurement via CT terminal	9	I* (white)	-	-
	10	I (blue)

Connecting the cable for voltage measurement
Connect the cable for current measurement
only then connect the CT terminal

The cable length of the CT terminal is 6 m. If the cable is too long, it can be cut to length. If the cable is too short, it can be extended up to 15 m.

The connection for communication with the Inverter one is made via the direct connections 24 and 25.

The meter adapter is included in the scope of delivery of the Inverter one.

Connecting the meter adapter for the connector to the inverter
Wire end ferrules are only necessary if stranded wires are used
Connect the meter to the inverter using the meter adapter

DDSU communication - pin assignment

	Pin of the meter	Port/device	Conductor cross section	Outer diameter
Communication	24	Pin 1 Meter adapter on inverter	0.25 ^mm2 - 1.5 ^mm2 shielded, two-core twisted outdoor cable, min. Cat 5e	4 mm - 11 mm
	25	Pin 2 Meter adapter on the inverter
	5	Pin 485A on the SOLARWATT Charger (optional)
	6	Pin 485B on the SOLARWATT Charger (optional)

Attention

Torque connection screws 3 and 4:
max. --> 1.7 Nm
recommended --> 0.9 to 1.1 Nm.

Torque of clamping screws 5, 6, 9, 10, 24 and 25:
recommended --> 0.15 to 0.25 Nm.