I have several 800A Micrologic 2 MCCBs with only three adjustable settings Ir,tr and Isd. Ir is set at 0.7, tr is set at 4s at x6 Ir and Isd is set at 5. Is this not incompatible? My reckoning is that the Ir is 560A, tr holds an overload of 3360A for 4s but the short time pick up pulls the breaker out instantaneously at 2800A. All the devices are similarly set. There are no issues as a result but just wondering.
Now, in your case the region 2 gets cut off before the 6X value, so runs from Ir to about 5Ir. It is still useful and makes it behave rather more like an MCB curve B than a C
This is delay at 6 times, so at 5 times it will be 70 odd percent of that time
Now, in your case the region 2 gets cut off before the 6X value, so runs from Ir to about 5Ir. It is still useful and makes it behave rather more like an MCB curve B than a C
This is delay at 6 times, so at 5 times it will be 70 odd percent of that time