Low Voltage Switchboard Short circuit withstand

[el_diegol]

Hello everyone,

This is the situation, I have received from a switchboard manufacturer a type test report, issued by a local authority, confirming that the switchboard is rated for 100kA. In the report are shown the internal arrangement of the busbars, structure of the switchboard, materials used, busbar sizes, etc. All seems to be OK.

Now I have requested the internal arrangement drawings specific to the project I'm running, and they look a bit different to me. They run busbars in locations not shown in the type test report, they have more breakers per sections than in the report (two vs. one in the report) and the internal spacing seems to be different dimension wise.

My question is: what are the key elements I need to look at to say that the test certificate given doesn't correspond to the switchboard being offered.

Many thanks!

 

[templdl]

Hello everyone,

This is the situation, I have received from a switchboard manufacturer a type test report, issued by a local authority, confirming that the switchboard is rated for 100kA. In the report are shown the internal arrangement of the busbars, structure of the switchboard, materials used, busbar sizes, etc. All seems to be OK.

Now I have requested the internal arrangement drawings specific to the project I'm running, and they look a bit different to me. They run busbars in locations not shown in the type test report, they have more breakers per sections than in the report (two vs. one in the report) and the internal spacing seems to be different dimension wise.

My question is: what are the key elements I need to look at to say that the test certificate given doesn't correspond to the switchboard being offered.

Many thanks!

Assuming that you have contacted the manufacturer was was their answer? Is it a UL listed switchboard?

 

[el_diegol]

Assuming that you have contacted the manufacturer was was their answer? Is it a UL listed switchboard?

That the certificate is valid and the design offered is covered by the certificate.

Is not UL certified, the manufacturer is based in Asia.

 

[kingpb]

Hello everyone,

This is the situation, I have received from a switchboard manufacturer a type test report, issued by a local authority, confirming that the switchboard is rated for 100kA. In the report are shown the internal arrangement of the busbars, structure of the switchboard, materials used, busbar sizes, etc. All seems to be OK.

Now I have requested the internal arrangement drawings specific to the project I'm running, and they look a bit different to me. They run busbars in locations not shown in the type test report, they have more breakers per sections than in the report (two vs. one in the report) and the internal spacing seems to be different dimension wise.

My question is: what are the key elements I need to look at to say that the test certificate given doesn't correspond to the switchboard being offered.

Many thanks!

It sounds like you have already identified the discrepancies. Make sure they put in writing that the type test covers the equipment shipped.

 

[templdl]

That the certificate is valid and the design offered is covered by the certificate.

Is not UL certified, the manufacturer is based in Asia.

I reread your OP, did I miss that?

 

[Jraef]

I reread your OP, did I miss that?

No, you didn't miss it, he didn't state it. But he IS from Great Britain, so that would imply that UL was unlikely.

A "type test report" for those of us in North America, is an IEC thing because they DON'T have independent 3rd party approval issues such as UL. Manufacturers are "self regulated", so users will demand a written document stating that they adhered to the specs, just in case it is later discovered that they didn't. Here in North America doing something like that risks losing your NRTL listing, which effectively puts you out of business. Elsewhere, the supplier might be on the hook for the costs of that SPECIFIC project, but is otherwise free to do business as they see fit. Having a written document STATING that they met specs, means that if it turns out otherwise, they KNOWINGLY violated them and it puts them on the liability hook.We don't need all that rigmarole here.*

el_diegol,
A type test report is simply a report from the supplier stating that the equipment meets project SPECIFICATIONS, not necessarily drawings. The number and arrangements of devices in the switchboard, even the locations of bus bars etc., is not inherently covered in a type test report, unless your written specifications were extremely specific in those regards. Most of the time they are not, your specs likely called out for meeting certain standards of construction and design, plus maybe testing procedures and acceptable limits within industry standards. As long as they have not deviated from those limits AS SPECIFIED, the type test report may be perfectly valid. Your project tender drawings may have indicated a desired device and bus arrangement, but that is often in conflict with standard designs from different suppliers, so are often deviated from in deference to a supplier's standard designs so as to not incur additional costs, as long as the written specifications are adhered to.

So the onus is now upon YOU to investigate the details of their equipment design against your written specifications. That's the other side of the coin for you not having 3rd party approval requirements as we do.

*The reason I know this now, is that 2 years ago I did a huge solar project for a company based in Spain, where everything was engineered there based on IEC standards, but required, obviously, to meet US standards for installation, which in Nevada meant UL listing of everything. So we submitted on standard UL845 listed MCCs and UL1558 Switchgear, which looked NOTHING like what they wanted and had specified. I got into this "type test report" issue with the Spanish engineering firm big time; they did NOT understand that we cannot just re-design UL listed equipment to look like IEC specified equipment, and kept insisting on this "type test report" issue, which we could not really supply.