CSA Motor in the United States

[SteveS0118]

We have a customer requesting us to use a motor that is listed by CSA to standard C22.2 No. 30 in a Class I, Division 1, Group D location in a wastewater plant. Would this standard be acceptable in the United States? Generally, we see them listed to the UL 1203 standard.

To go into some more detail, the motor is 4160V, 500HP, and will be run off a VFD with a 2:1 turndown. The customer originally requested us to use a non-inverter rated ATEX Ex d motor. After several weeks of going back and forth they accepted that the US does not recognize the European flameproof ATEX rating in a Class I, Div. 1 area. Now they have found a motor manufacturer that is willing to have CSA custom certify an ATEX motor for use in a Class I, Div. 1 environment for an extra $145,000. (Luckily this is a change order, so we are not on the hook.)

We suggested using a Class I, Div. 2 motor with a purge kit. It is our understanding that a motor shop would need to remove the nameplate when the purge kit is added. However, according to NEC 501.125 (A) (2) the purge kit would be acceptable since it would meet NFPA 496.

At the end of the day, our customer wants the nameplate to show Class I, Div. 1 (even if it is evaluated to a CSA standard instead of UL). We are trying to provide the most cost effective solution that meets the United States standards for our customer. Any guidance would be appreciated.

 

[augie47]

Approval of equipment is up to Authority Having Jurisdiction so in the end up would be their call but CSA is a Recognized National Testing Lab and if the motor is marked correctly for the environment it would be acceptable by more inspectors that I know.

 

[rbalex]

I agree with Augie that a CSA listing should be acceptable. One caveat is CSA is technically only a NRTL when they certify to a Recognized American National Safety Standard.

That said, the critical term in Section 501.125(A)(1) is identified. It does not necessarily mean listed or labed in the Section 100 (Definitions) since.

Canada is much further along than the US in understanding IEC type equipment. It should be understood that the minimum experimental safe gap (MESG) and minimum ignition energy (MIE) tests are significantly different between "Ex d" and explosionproof. Nevertheless explosionproof in both countries is about the same.

 

[SteveS0118]

Thanks for the information. We are much more comfortable with the city's decision after your responses.