Solid State Relays (SSR)
A solid state relay (SSR, semiconductor relay) is a contactless relay that switches the load with semiconductor elements such as a triac, thyristor or transistor instead of a mechanical contact. Because it has no moving parts, it operates silently and has no contact wear; for this reason it is used on loads that switch on and off frequently, such as resistive heaters and ovens. This category includes single-phase and three-phase relays with load currents such as 25 A, 40 A and 100 A and 3-32 V DC or AC control, and analog models with 4-20 mA, 0-10 V or potentiometer input, from the brands Isıso, Enda, Siemens and Soljex. Select the SSR according to the load type (AC or DC, resistive or inductive), the load current and voltage, the control signal, the number of phases, and whether you need zero-crossing or analog-input operation. The rated current is given for a specific cooling condition; check whether a heat sink is included and the manufacturer's current-temperature curve. An SSR should not be confused with a contactor or an electromechanical relay: it passes a leakage current even when off and does not physically isolate the circuit, and models with AC outputs cannot switch off a DC load.
Products
- Siemens 3RF2130-1AA04 Solid-State Relay Control Voltage 24 V DC — Siemens · SKU: 3RF2130-1AA04 · TRY 4,932.00 · Made to order
- Siemens 3RF2120-1AA02 Solid-State Relay Operational Voltage 24-240 V AC — Siemens · SKU: 3RF2120-1AA02 · TRY 4,100.00 · In stock
- Schneider Electric SSP1A125BDE 1P SSR 25A 24-480VAC Zero,5-24VDC — Schneider Electric · SKU: SSP1A125BDE · TRY 2,251.79 · Made to order
- Schneider Electric SSP1A1125BDE 1P SSR 125A 24-480VAC Zero,5-24VDC — Schneider Electric · SKU: SSP1A1125BDE · TRY 3,447.18 · Made to order
- Siemens 3RF2120-1AA04 Solid-State Relay Operational Voltage 48-460 V AC — Siemens · SKU: 3RF2120-1AA04 · TRY 4,654.00 · Made to order
- Schneider Electric SSM1A112BD Solid State Relay — Schneider Electric · SKU: SSM1A112BD · TRY 4,976.17 · Made to order
- Schneider Electric SSD1A320M7C1 Solid State Relay — Schneider Electric · SKU: SSD1A320M7C1 · TRY 9,229.55 · Made to order
- Schneider Electric SSP1A150M7T Solid State Relay — Schneider Electric · SKU: SSP1A150M7T · TRY 5,810.17 · Made to order
- Siemens 3RF2130-1AA02 Solid-State Relay Control Voltage 24 V DC — Siemens · SKU: 3RF2130-1AA02 · TRY 4,617.00 · Made to order
- Schneider Electric SSP1A110BDE 1P SSR 10A 24-480VAC Zero,5-24VDC — Schneider Electric · SKU: SSP1A110BDE · TRY 1,656.87 · Made to order
- Siemens 3RF2320-1AA04 Solid-State Relay Control Voltage 24 V DC — Siemens · SKU: 3RF2320-1AA04 · TRY 7,733.00 · Made to order
- Schneider Electric SSP1A125BDT Solid State Relay — Schneider Electric · SKU: SSP1A125BDT · TRY 4,531.38 · Made to order
- Siemens 3RF2320-1AA02 Solid-State Relay Control Voltage 24 V DC — Siemens · SKU: 3RF2320-1AA02 · TRY 6,648.00 · Made to order
- Schneider Electric SSD1A335BDC1 Solid State Relay — Schneider Electric · SKU: SSD1A335BDC1 · TRY 9,229.55 · Made to order
- Siemens 3RF2310-1AA04 Solid-State Relay Operational Voltage 48-460 V AC — Siemens · SKU: 3RF2310-1AA04 · TRY 7,556.00 · Made to order
- Siemens 3RF2020-1AA02 Solid-State Relay Operational Voltage 24-230 V AC — Siemens · SKU: 3RF2020-1AA02 · TRY 4,452.00 · Made to order
- Schneider Electric SSP1A475M7T Solid State Relay — Schneider Electric · SKU: SSP1A475M7T · TRY 6,449.57 · Made to order
- Schneider Electric SSD1A320BDC1 Solid State Relay — Schneider Electric · SKU: SSD1A320BDC1 · TRY 7,700.56 · Made to order
- Schneider Electric SSP1A125M7T Solid State Relay — Schneider Electric · SKU: SSP1A125M7T · TRY 4,976.17 · Made to order
- Siemens 3RF2410-1AB55 Solid-State Relay Operational Voltage 48-600 V AC — Siemens · SKU: 3RF2410-1AB55 · TRY 21,720.00 · Made to order
- Schneider Electric SSD1A335M7C1 Solid State Relay — Schneider Electric · SKU: SSD1A335M7C1 · TRY 9,952.35 · Made to order
- Siemens 3RF2030-1AA02 Solid-State Relay Control Voltage 24 V DC — Siemens · SKU: 3RF2030-1AA02 · TRY 4,656.00 · Made to order
- Schneider Electric SSP1A150BDE 1P SSR 50A 24-480VAC Zero,5-24VDC — Schneider Electric · SKU: SSP1A150BDE · TRY 2,785.55 · Made to order
- Schneider Electric SSP1A190BDE 1P SSR 90A 24-480VAC Zero,5-24VDC — Schneider Electric · SKU: SSP1A190BDE · TRY 3,196.98 · Made to order
- Siemens 3RF2410-1AB45 Solid-State Relay Operational Voltage 48-600 V AC — Siemens · SKU: 3RF2410-1AB45 · TRY 20,758.00 · Made to order
How to choose Solid State Relays (SSR)
A solid state relay (SSR, semiconductor relay) is a contactless relay that switches the load with semiconductor elements such as a triac, thyristor or transistor instead of a mechanical contact. Because it has no moving parts, it operates silently and has no contact wear; for this reason it is used on loads that switch on and off frequently, such as resistive heaters and ovens.
- Separate sensing, motion control, logic processing and operator interface requirements.
- Select signal type, supply voltage, communication protocol and I/O count for the machine network.
- Verify housing size, sensing distance and PNP/NPN output polarity against the PLC input card.
Frequently asked questions
What is Solid State Relays (SSR) and where is it used?
A solid state relay (SSR, semiconductor relay) is a contactless relay that switches the load with semiconductor elements such as a triac, thyristor or transistor instead of a mechanical contact. Because it has no moving parts, it operates silently and has no contact wear; for this reason it is used on loads that switch on and off frequently, such as resistive heaters and ovens.
What should I compare when choosing Solid State Relays (SSR)?
Select the SSR according to the load type (AC or DC, resistive or inductive), the load current and voltage, the control signal, the number of phases, and whether you need zero-crossing or analog-input operation.
Where can I find technical details for Solid State Relays (SSR) products?
A solid state relay (SSR, semiconductor relay) is a contactless relay that switches the load with semiconductor elements such as a triac, thyristor or transistor instead of a mechanical contact.
Solid State Relays (SSR) Selection Guide: Technical Criteria and Engineering Practice