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What trip units are used in J and L frame mission critical breakers? Does it matter for selective coordination?

Issue:
What trip units are used in J and L frame mission critical breakers?  I was looking in the following document: Short Circuit Selective Coordination for Low Voltage Circuit Breakers 0100DB0501, and it just says WU for the type, but does not tell me what trip unit that is used.  Does it matter for selective coordination?

Product Line:
J and L frame mission critical breakers and trip units

Environment:


Cause:
Document: Short Circuit Selective Coordination for Low Voltage Circuit Breakers 0100DB0501 not clear on what trip unit is used.

Resolution:
It does not matter for selective coordination.  Available mission critical trip units are:
J-frame:  3.2-W, 3.2S-W, 5.2A-W, 5.2E-W, 6.2A-W, 6.2E-W     
L-frame:  3.3-W, 3.3S-W, 5.3A-W, 5.3E-W, 6.3A-W, 6.3E-W

Micrologic Electronic Trip Units In the Type column of tables covering PowerPact™ H, and J circuit breakers,
the “U” character in the third position stands for Micrologic Electronic Trip Unit.
For example:
• HDU360 - 3 pole 60A HD breaker with Micrologic trip unit.
• JLU3250 - 3 pole 250A JL breaker with Micrologic trip unit.

J- and L-Frame Mission Critical Circuit Breakers
In the upstream column of tables covering J- and L-frame mission critical
circuit breakers, there are “WU” characters in the third and forth positions
that stand for mission critical circuit breakers with Micrologic electronic trip units.
For example:
• JLWU–3 pole 250 A JL mission critical circuit breaker with Micrologic trip unit
• LDWU400–3 pole 400 A LD mission critical circuit breaker with Micrologic trip unit

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