I got a job to do a household appliances with wireless remote control. I’m working as embedded developer in current company, but we haven't had to certificate our solutions and I'm looking for advice.
The first level of this job is to make a prototype of the machine. However I want this prototype not to demand too many modifications during the certifications process before entering the EU market.
As for my internet research, I know that the necessery things to do are: certification EMC, RED, LVD and additionally norms IEC-60335 and IEC-60730 for Class-B machine (household appliances).
Has anyone of you designed or made a household device controled by MCU?
Is following norms IEC-60335 and IEC-60730 demanded? Are making the tests obligatory for the norms? Or only the producer statement is enough to let the product enter the market?
What documents are needed to conduct the test of this kind of appliances in external laboratory (PCB circuict schematic, list of norms, elements list, software architecture, code source, code/libraries certifications etc.)?
For Class-B device necessery is to use mechanisms self-test peripherals of MCU (such as CPU, RAM, Flash, Watchodgs etc.)?
But the producer of the chip (Nordic Semiconductor - nRF5) I chose doesnt provide the self-test library or the support for this kind of tests. Can I go through the certification process implementing this kind of self-test by my own or using for example only watchdogs?
For example, ST Electronics provides certified library of this type of self-test for free. However its wireless modules are more difficult to get and much more expensive than nRF modules.
I would like to use nRF modules because its precertified with FCC/IC etc. And here I have another question: whether the certification of my own remote controller with precertified module on my own PCB circuit with battery (CR2032 3V3) supply and 4 buttons is as expensive as using a not precertified radio module?
To precise: my goal is to designing and making a prototype a remotely controlled cooker hood. I have wanted to use RF modules in remote controller and mainboard cooker hood. The LED lights and turbine (low voltage 10V) would be controlled by the MCU. The voltage to mainboard would be provided by the 12V power supply.
As I found out the norm IEC-60730 divides the household devices in to 3 classes:
- Class A - Control functions, which are not intended to be relied upon for the safety of the equipment. Examples are: room thermostats, humidity controls, lighting controls, timers, and switches.
- Class B - Control functions, which are intended to prevent unsafe operation of the controlled equipment. Examples are: thermal cut-offs and door locks for laundry equipment.
- Class C - Control functions, which are intended to prevent special hazards (e.g., explosion of the controlled equipment). Examples are: automatic burner controls and thermal cut-outs for closed, un-vented water heater systems. [https://www.nxp.com/docs/en/application-note/AN3257.pdf]
Theoretically it would be possible to define that control as Class A - lightning control, timers and switches. It would make the process of designing easier, because the software systems of safety aren't demanded in this class. Unfortunately the control of a turbine makes this project as device of class B.
Thank you for your answers, I hope they would be useful to others in the future, because the subjects of meeting the standards, safety regulations, certification of products and the right way of conducting the project are not well described on the internet and this is the next step after the own DIY projects.