Spindle/VFD and the Ontario Electrical Safety Authority

This post is targeted at Canadian users.

I have the OF X-50 with the Z-20 Heavy Duty Z Slider.

I am located in Ontario Canada.

I am looking for an 80 mm Spindle and VFD with a certification that is recognized by the Ontario Electrical Safety Authority. The ESA has jurisdiction over electrical products and electrical inspections here in the province of Ontario.

The ESA website says: ”Before an electrical product or piece of electrical equipment is used, sold, displayed or advertised for sale in Ontario, it must be approved by an accredited certification or evaluation agency. The item must carry the official mark or label of the agency which indicates that the product has been independently assessed for safety”. They also say “Installation and connection of unapproved electrical equipment is against the law”.
Reference: Search for an Approval Mark - ESA

This document identifies the approvals recognized by the ESA: https://dev.esasafe.com/assets/files/esasafe/pdf/Electrical_Safety_Products/Bulletins/2-7-.pdf

Many of the VFD/Spindle products available, such as those offered by PWN CNC, appear to only have a CE declaration by the manufacturer rather than an evaluation and approval by a recognized independent third party. In an email exchange with Daniel Moran of PWN CNC, he confirmed to me that their VFDs have a CE mark on the label and he is not aware of any other certifications.

The ESA document clearly states that “the CE mark is a manufacturer’s self-declaration mark not recognized in Canada.”

Has anyone navigated this issue and successfully sourced/installed a VFD and Spindle with an ESA recognized approval on their Onefinity CNC that uses the Buildbotics controller?


I can not speak to your last question, but had looked into this topic when I started sourcing equipment and building my control panel.

From various online resources and discussions, some thoughts that come to mind are…

*even if individual components, like a VFD, carry the UL/c-UL/UL certifications, it is the whole assembly that must also be taken into consideration

*I do not believe (any/most) of the hobby kits offered follow the exact installation/circuit recommendations provided in the VFD’s manual. On top of that, all the components used in each kit should be certified, and then the entire assembled unit.

*there are many 3rd party companies that are accredited to do field inspections of equipment

*business that add equipment (i.e., from overseas) that do not come pre-certified, often spend many thousands of dollars to have them inspected and certified on site for the safety of their employees and for insurance claims

*I did not go so far as contacting a 3rd party to see if they do field inspections of residential “hobby” shops, but I am guessing the inspection of my panel alone - which has many components - would be well over $1K. I would also need to have my VFD enclosure inspected as well. I did my best to buy high quality and appropriately certified components, and follow best practices for their installation, but I know it is a risk I am taking.

I know there are several experienced professionals in our forum who may also add their insights to this topic.

As regards Ontario ESA, I believe that CSA would overide a provincial requirement.
Back when I worried about such things, I believe the Canadian govt agreed to accept U/L certification as acceptable, (this may have been changed)
Further the biggest worry to me would be if my property insurance carrier tried to hide behind any lack of certification, I would legally challenge them to prove that the equipment was in use, and or caused the fire.
Further, in BC anyway, if you hire a licensed electrical contractor to make the electrical connections, you are pretty much covered legally.

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I was speaking more about the hardware and components in a system (like the Onefinity control box), vs electrical connection/inspection of the installation.

Before I retired 25 yrs ago, was involved in electrical connections and installations for rapid transit (skytrain) rails, Hospital, School, Industrial and residential installations and procurement. In BC if your electrical contractor makes the connections and the devices were deemed to be legally acceptable. We used to have an engineering firm that could write CSA approvals and I cannot for the life of me remember (or google) their name.

Intertek is one that I have seen advertised for field evaluation services.

Just occurred to me that if a regulation has never been challenged in court, it does not carry much weight. Legal rulings are pretty much the last word.
Gonna go & make some shavings.


Navigating the requirement for an ESA-approved VFD and spindle for your Onefinity CNC in Ontario can be a bit tricky due to the specific regulations outlined by the Electrical Safety Authority. As per the ESA guidelines, electrical products must carry an official mark or label from an accredited certification agency to ensure safety compliance.

Currently, many VFD and spindle products, like those from PWN CNC, only carry a CE mark, which is not recognized in Canada as a sufficient certification according to ESA standards. This has posed challenges for users seeking compliant equipment for their projects involving Electrical Estimating.

To address this, some users have explored options such as:

  1. Seeking CSA Certification: While the ESA document emphasizes the need for an approved mark, some users have speculated about CSA (Canadian Standards Association) certification potentially overriding provincial requirements. However, specific confirmation from CSA or a recognized third-party certification agency would be necessary to ensure compliance in Electrical Estimating.
  2. Consulting with Electrical Contractors: Engaging a licensed electrical contractor for installation can provide legal coverage in Ontario. Contractors can ensure that connections meet regulatory standards, potentially mitigating concerns related to equipment certification during Electrical Estimating.
  3. Insurance Coverage Considerations: Some users have raised concerns about property insurance requirements. Ensuring that equipment meets regulatory standards could be crucial in the event of an insurance claim related to Electrical Estimating.

In conclusion, while navigating this issue for Electrical Estimating, it’s essential to verify with the manufacturer or supplier whether their products have undergone independent assessment and carry a recognized approval mark as required by the ESA. Consulting with electrical professionals and possibly exploring CSA certification could provide clearer pathways to compliance in Ontario.