Fail Type 7

Connect Fail Type 7

I noticed a question back in 2019 with regard to fail type 7 as below.

Under the fail help, fail type 7 is determined as "Fails as no I2t data is available for the devices, assume a failure by default".

I assume that the I2t data for the specific devices is not present in the data file for that particular device, in this instance Schneider Mirologic ACB's.

With no I2t data the calculation defaults to unlimited energy let through, which then fails the k2s2 > I2t test.

As such I'm left with a failure on the main supply where I'm using Schenider ACB's on both the LV supply (in this case an outgoing transformer) and on the incoming side of the main panel board.

Using the generic ACB on the LV feeder overcomes the issues, but then gives me a discrimination problem with the down stream Schneider ACB.    

Why is the I2t data not included in the calculation? And how do I overcome the issues?

Schneider ACB's must be one of the most commonly used protective devices of this type. 

I too have the need to produce calculations for scrutiny by a Consultant.

When will this issue be resolved?  Using a Generic ACB does not satisfy the Consultant, they require the verified calculations using the devices we will be installing.

Please advise when a fix will be provided.

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