CE Certification

[dc42]

We have spent considerable sums of money doing CE EMI, RED and RF immunity tests. The Duet WiFi internal antenna version has passed these tests in a bench setup without requiring a metal enclosure. The Ethernet and external antenna versions require additional shielding to be within the limits. All Duets satisfy the RoHS element of CE certification.

As has already been said, it's actually the whole printer that needs to be certified. What we as a component manufacturer can do is provide guidance to our OEMs on the measures they may need to take to achieve certification of their printers, and provide assurance that Duets are RoHS compliant.

[DocTrucker]

@bearer yes, ATEX rated stuff for example is far stricter. Most of the reason you can see near identical ATEX and non ATEX at vastly different prices.

It's a little frustrating to see some of the crap things with CE marks that can't of had a decent risk assessment, or simply don't care. I'd love to make and sell kit bundles but the marguns are super tight, especially if you do it all right!

[DocTrucker]

@dc42 Didn't mean to imply you hadn't put effort in to this area, that wasn't my intention. Moat of my grumbles are aimed firmly at the non-duet printers.

[A Former User]

@DocTrucker with the risk of getting of topic, there was no difference in the CE testing for atex vs non atex, just that for atex the tests had to be performed by a notified body (in adittion to the atex specific tests). My point was just to say CE is not exclusively self certified (and if the CE mark is followed by some numbers its to identify the notified body ... but ofcourse anyone could print CE₁₂₃)

[stefma]

@dc42 Can you give a rough idea on the tasks which need to be done to get certification? I assume a grounded metal-enclosure is required. Do the motor-cables need to be shielded,...?

[DocTrucker]

@stefma you don't 'get certification' apart from in the instances that @bearer mentioned. Other than that you are signing a certificate to say you have built it to comply with the necessary regulations that cover such aspects such as EMC radiation, low voltage wiring, and have a decent risk assessment.

Best advice is to get some CE certificates for machines like the Ultimaker and read through the standards/regulations and standards they list.

Incase you are not aware obaying the regulations is a legal requirement, and following the standards is a way to demonstrate you have done so.

[DocTrucker]

@stefma but to answer your question another way following best wiring practice would not hurt.

Therefore correct wire colours, type, and guage for the current and mechanical loading. Shielding may not be needed but better to have with than without. Also look at the RepRapPro products, they even had metal shielding around the short sections of flying wire between the cable sheath and the stepper plug. Grounding stepper bodies would be necessary too.

If using wifi I think the noise regulations are relaxed a bit as the unit is designed to radiate EMC in order to connect to the network. Metal enclosure of the pure ethernet controllers has already been mentioned.

[dc42]

@stefma said in CE Certification:

@dc42 Can you give a rough idea on the tasks which need to be done to get certification? I assume a grounded metal-enclosure is required. Do the motor-cables need to be shielded,...?

There are various strands to CE certification:

• EMI
• Electromagnetic immunity
• Radio Equipment Directive (applies to Duet WiFi)
• RoHS
• Low Voltage Directive (where "Low voltage" encompasses mains voltage)

and probably others that apply to a complete printer.

We're still drafting our CE guidelines, and unfortunately CE testing is suspended because of the current situation. However:

• Duet WiFi internal antenna version 1.04 passes EMI, immunity and RED without needing to be in a metal enclosure. If you use a PanelDue with it then you need a ferrite bead on the cable between the two at the PanelDue end, and possibly also at the Duet end.
• Duet Ethernet and Duet WiFi with external antenna don't pass EMI when outside a metal enclosure. We have more testing scheduled with the WiFi external antenna.
• Duet 3 v0.6 doesn't quite pass EMI outside a metal enclosure. Version 1.0 has some design changes, which we expect make it compliant without an enclosure, at least in standalone mode.

All Duets are RoHS compliant. The LVD doesn't apply because the voltages are too low.

Regarding stepper motor cables, it depends on the board and the current setting. We've done more work on this for Duet 3 because of the higher currents supported. Duet 3 tool boards are fine with unshielded cables. Duet 3 main boards currently need shielded stepper motor cables, but the next design revision should be within limits with unshielded twisted pair cables. Duet 3 expansion boards already have this design change incorporated, so they should already be OK with unshielded twisted pair. Unshielded twisted pair CAN cables are OK.

HTH David

[stefma]

@DocTrucker thanks for your input! I know that I won't get a certificate from an authority but that I have to fulfill some requirements.
But I am pretty lazy and if somebody already knows common issues then I don't want to reinvent the wheel

Best regards

[DocTrucker]

@stefma always worth asking! I've been dancing on the edge of this a little myself for some time. Another aspect of this is CE marking makes using the machines in a company easier. Getting employees to use a CE marked machine is straight forward. With out it (like all of my home-build machines) you need to do a very thorough risk assessment to comply with the PUWER regulations.

It's a little sore spot for me really. I understand the need for it, but some of the CE marked crap you see clearly shows it is worth more from some suppliers than others. With imported goods it is the CE documentation is the responsibility of the importer. You can see that some budget machines that generally come in through Joe Bloggs garage it wouldn't be difficult for the ebay company to disappear if there were any difficulties that got the HSE asking for the documentation. This behaviour makes the field very difficult to operate in as I would be inclined to do a thorough job and get myself confident with the compliance. This is of course expensive in both cash and time.

[stefma]

@DocTrucker yes, thats the point... You can do whatever you want in your own garage. But since I'm within a company environment where employees are supposed to work with that machine CE is crucial for me.

[DocTrucker]

@stefma likewise if my company ever gets past just me. A solid risk assessment that has been reviewed by a second competent person should be ok from what I understand.

[Tricep terry]

@dc42 since this post is rather old by now already, what is the current state of the boards also for the Duet 3 mini 5+ wifi with external antenna? And what are the wifi power ratings of the boards?

[DocTrucker]

@Tricep-terry likely stating the obvious but a CE marked board won't make the whole machine CE marked. As a community the best we could do for home brewed machines is to provide example risk assessment and mitigation documents and user manuals which can be adapted by others to suit their machines. This would result in a set of documentation that demonstrates due diligence on making a custom made machine safe for use by employees, but it would still be significant work, and only worth the MBs of storage it is written on if effort is put in.

I've got a small business spec machine that I'm now rebuilding. That could be the start of example docs if they haven't happened already in the long periods of my abscence from this forum!

Edit: I believe the best duet3D could provide with the board is a certificate of incorporation.

[Tricep terry]

@DocTrucker Many thanks for your quick response, I'm aware of what you are stating and of course, agree with it, however, I was just wondering since they mentioned that they are drafting the CE guidelines, what the current state of it is.

Also in several posts, they mentioned upcoming changes that would improve certain things which may or may not reduce the required level of protection for the boards in terms of EMC, but then the results of those changes were not communicated anymore.

And of course, duet cannot provide the necessary documentation that would make any machine built with their board automatically pas CE certification, but some updated requirements on these things after the tests / general guidelines would be sweet.

[DocTrucker]

@Tricep-terry I'm guessing that work may have been to support people that are bulk buying boards for machines they are selling commercially. If the customers (rather than duet) funded the work they may not have wanted to share it. That said, They may just have their hands full!