Transformer
Figure 1: Auto Coordination Options - Transformer
Option | Description |
---|---|
NEC Requirements for Transformer Protection |
The table is the NEC Table 450-3(A) for transformer primary over 600V. The table shows the maximum rating or setting of over current protection for transformers. You can change the values in the spreadsheet. |
With SSTs, apply transformer FLA NEC limits using |
When setting SST for transformer FLA, the LTPU is set based on the following selections:
|
Allow one setting past transformer FLA NEC limit for LTPU selection |
Selecting the check box increases LTPU setting by one past the selected transformer FLA NEC limit. If the check box is not selected, LTPU is set as originally specified. |
How should the LTPU selection of LV devices be prioritized? |
LTPU coordination is selected by coordinating with other protective devices or with maximum transformer FLA.
|
Minimum gap between inrush and relay |
Sets the relay time delay at specified seconds higher than the transformer inrush time. |