Instantaneous Protection
Presentation
Instantaneous protection on MicroLogic 5, 6, and 7 trip units protects all types of electrical distribution applications against very high short-circuit currents.
It is identical for MicroLogic 5, 6, and 7 trip units.
Operating Principle
Instantaneous protection is definite time, set as Ii pickup and without a time delay.
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The instantaneous protection setting is:
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Setting the Instantaneous Protection
Set the Ii pickup:
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With the keypad on the MicroLogic trip unit
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With EcoStruxure Power Commission software (password-protected)
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By sending a setting command using the communication network (password-protected)
Ii Pickup Setting Values
The Ii pickup setting value is in multiples of In.
The default Ii pickup setting value is the maximum setting value (15, 12, or 11 x In according to trip unit In rating)
The following table shows the setting ranges and increments according to the MicroLogic trip unit In rating.
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Trip unit In rating |
Setting range |
Increments |
|---|---|---|
|
100 A and 160 A |
1.5–15 x In |
0.5 x In |
|
250 A and 400 A |
1.5–12 x In |
0.5 x In |
|
630 A |
1.5–11 x In |
0.5 x In |
The accuracy range is +/-10%.
The hold time is 10 ms.
The maximum breaking time is 50 ms.