3RF2070-1AA45

What does this device do?

This is a single-phase solid-state relay designed to switch AC loads using a DC control signal. It uses zero-point switching, which means it turns on at the AC waveform zero crossing to help reduce electrical noise and switching stress in suitable applications.

What input and output voltages does it work with?

The control side operates on 4 to 30 V DC. On the load side, it is designed for 48 to 600 V AC at 50/60 Hz, with an operating range of 40 to 660 V AC.

What current rating should I use for application sizing?

For resistive duty, the unit is rated up to 70 A at AC-1 at 400 V. For AC-51 duty, the rating is 50 A. When sizing a relay for a real installation, the load type and thermal conditions should be considered carefully.

Is this suitable for single-phase applications?

Yes. It is a single-phase relay with one main pole and is intended for switching single-phase AC loads.

What is zero-point switching and why does it matter?

Zero-point switching means the relay switches on when the AC voltage crosses zero. This can help reduce inrush effects and electromagnetic disturbance compared with random turn-on methods, particularly in heating and other resistive load applications.

What kinds of loads is it commonly used for?

It is commonly used for single-phase electric heating circuits and other AC loads where quiet, fast, wear-free semiconductor switching is preferred over mechanical contacts. It is especially attractive where frequent switching is required.

Does it have any auxiliary contacts?

No. This unit does not include auxiliary NO, NC or changeover contacts.

How quickly does it switch on and off?

The stated switch-on delay time is 1 ms plus up to one additional half-wave, and the off-delay time is also 1 ms plus up to one additional half-wave.

What are the physical dimensions?

The housing is compact, with an overall width of 45 mm, height of 58 mm and depth of 48 mm. The slim width can be useful where panel space is limited.

How is it mounted?

The relay is designed for screw fixing and supports side-by-side mounting. The fixing screw thread is M4, with a maximum fastening torque of 1.5 N·m.

What type of terminal connection does it use?

It uses screw-type terminals for both the main circuit and the control circuit. Main contact screws are M4, while auxiliary and control terminal screws are M3.

What cable sizes can be connected?

For the main contacts, solid conductors from 1.5 to 6 mm² and finely stranded conductors with end processing from 1 to 10 mm² can be connected. For control connections, the accepted range is typically 0.5 to 2.5 mm² depending on conductor type.

What tightening torque should be used on the terminals?

For the main contacts, the recommended tightening torque is 2 to 2.5 N·m. For the control terminals, it is 0.5 to 0.6 N·m.

What protection rating does the enclosure offer?

The front protection rating is IP20. It is also described as finger-safe from the front when mounted correctly.

What are the operating temperature limits?

The operating ambient temperature range is -25 to +60 °C. Storage temperature range is -55 to +80 °C.

Does this relay generate heat during operation?

Yes. As with solid-state relays generally, heat dissipation should be allowed for in panel design. For this model, power loss at rated current is specified at 94 W in hot operating state, so thermal planning is important.

What is the minimum load current?

The minimum operating current is 500 mA. This is worth checking if the relay is being considered for very small AC loads.

What blocking voltage does the output stage provide?

The maximum permissible blocking voltage at the thyristor is 1,200 V. This is one of the key electrical characteristics of the 3RF2070-1AA45.

Are there recommended fuse options for semiconductor protection?

Yes. Datasheet-listed examples include 3NE1020-2 as a full-range R fuse link, 3NE8020-1 as a back-up R fuse link in NH design, and 3NC2280 as a back-up R fuse link in 22 x 58 mm cylindrical design. Additional gG and NEOZED fuse references are also listed.

What EMC characteristics are stated for this unit?

The relay is specified with EMC performance data including burst, surge, HF immunity and electrostatic discharge values, along with CISPR11 Class A conducted emissions for industrial environments and Class B field-bound HF interference emission for domestic, business and commercial environments.