Solid State Relays with Low Electromagnetic Noise Emission

EMC optimized Solid State Relays

celduc Relais has just launched a new range of EMC optimized Solid State Relays (with low electromagnetic emission – low RFI) : our « SON » range. These relays are particularly suitable for applications where electromagnetic noise must be limited : household and electrical appliances, information technology and medical equipment.

For celduc, the major EN standards for Low Electromagnetic Noise Emission are EN55022, EN55011 and EN55014 which represent the main categories for electrical appliances.

At 150Khertz the emitted noise at Quasi-Peak shouldn’t exceed:

-79dBµV for class A appliances

-66dBµV for class B appliances

Example of conducted emission noise level for a standard Solid State Relay used to control a resistive load AC-51 8.6A @ 400VAC.

Tests performed in compliance with EN 55014 in quasi-peak

We record 78dBµV @ 150Kherts which is acceptable for an industrial application, but not for a domestic use as we are over the limits of 66dBµV

Same test performed with our new SON Solid State Relay EMC optimized.

We record a conducted emission noise level of 56dbµV @ 150Khz which is < 66dBmicroV

You can find standard « low noise » SSR on the market but those are limited to low switching current of 5A for domestic applications or to low inductive loads, while lots of pure resistive loads applications have high emission noise.

Our new EMC optimized SON range meets these requirements (Conducted emission noise level < 66dBµV) and can control class B appliances on pure resistive loads. Here are the current limits :

-CISPR 11 class B, group 1 : 220V 40A

-CISPR 22 class B : 400V 27A

celduc's ordering part numbers are : SON845040 and SON865040