How choosing the suitable PCB Solid State Relay to your application ?

celduc® relais offers a wide range of Solid State Relays for PCB : SK range available in different models. The product’s selection depends on your needs and on your application.

This range of PCB Solid State Relays (SSR) is particularly designed for heater, incandescent lamps and motor control . These SSRs can sustain very high surge currents (up to 1000A/10ms and 5000A2s), therefore they can easily be protected against short-circuit of the load and can drive loads with high inrush currents.

There are many different possible applications like motor switching (pump controls, motor reversing…), transformers control, food equipment (coffee machines , pizza ovens,…), lamps ( infrared lamps, traffic lights, lightning, …), medical equipments, ….

As all celduc SSRs, this range is built with high immunity components in compliance with european standards, with very low zero cross voltage.

Our complete range

SKA / SKB range : AC output

SKA/ SKB range is particularly adapted for driving small loads like contactors, electromagnets  lamps,…
–SKA range : up to 6A 230 or 400VAC, with built-in voltage protection, ideal for solenoid or motor control
-SKB range : up to 4A 230 or 400VAC for resistive loads.

SKD / SKLD range : DC output

Our SKD range with DC output (Bipolar technology) is designed for switching currents up to 3A 60VDC or 200VDC.
SKLD range (DC output – MOSFET technology) is designed for switching currents up to 12A 36VDC or 60VDC.

SKL range can be mounted on heatsink

SKL range, with AC output and a ceramic substrate, can be mounted on heatsink.
SKL Solid State Relays are available with current ratings from 16A to 75A.
For the power element, our SKL use TMS² technology reducing thermal stress and considerably improving life expectancy. Ideal for motor or lamps control (I²t up to 5000 A²s) with high inrush current as well as heating applications. Easy to protect against short circuit with micro circuit breakers.
The large range of SKL is designed to be installed with an external heatsink allows to reduce the sizes and the price of the equipment, everywhere , there are many SSRs and electronic control . The limit is given by the heatsink and the printed circuit board (generally 25/30A).
The incomparable characteristics of Itsm and I²t in this small size allows to sustain very high surge current on loads like lamps , motors or transformers.
The short circuit protection on the load can easily be made by Miniature Circuit Breakers.
All the range can be delivered with random control with a turn on time <50µs. These SSRs are adapted to phase angle control on different loads like lamps, … and to drive some loads like transformers.

SKH range with integrated heatsink

The SKH range is a “ready to use” range with integrated heatsink.

Selector Guide by application

Electrovalves, LEDs, Contactors

When the load is cold, the starting current can increase at a maximum of 1,4xIn.
In a normal case , with fuses protection (see application note : SSRs protection), choose the SSR in compliance with the nominal current and the starting current
Id=1,4xIn

Heating elements

When the load is cold, the starting current can increase at a maximum of 1,4xIn.
In a normal case, with fuses protection (see application note : SSRs protection), choose the SSR in compliance with the nominal current and the starting current
Id=1,4xIn

Infrared lamps or lighting

Incandescent lamps (infrared ,….) : AC-55b have generally inrush currents up to 8 or 10 times the nominal current . You can use the curve Itsm = f(t) , and take a good margin to have a correct lifetime expectancy.
Electric discharge lamp : AC-55a have also high inrush current, but in addition, there are overvoltage at the turn OFF. You should use 400VAC SSRs for 230VAC loads and add a varistor to protect the SSR.
Id=10xIn

Motors

Squirrel cage motors (AC-53) have generally inrush currents up to 5 or 8 times the nominal current. Standards give 8 x In during 1,6s. You should adapt the SSR to the motor nominal current x 8
Id=8xIn