Schneider Electric Class 615 dimensions Options for, Electronic Trip

Compact® NSF and NSJ 150 to 600 A Circuit Breakers

Section 4—Trip Units

Options for	Equipment Ground-fault Protection (T)—see (6) and (7), page 14
Electronic Trip
	Type		Residual Current
Unit STR53UP
	Tripping threshold	Ig	Adjustable (8 Settings) 0.2–1 x In
		Accuracy	± 15%
	Tripping time (ms)	Max. overcurrent time before tripping (Tg)	Adjustable (4 Settings + Constant I2t Function) 60, 140, 230, 350
		Total Breaking Time	-140, -230, -350, -500

Ammeter (I)

06153068
			A
In	I1	I2	I3

A digital display continuously indicates the current of the phase with the greatest load. By pressing a scroll button, it is also possible to display successively the readings of I1, I2, I3 and I neutral. LEDs indicate the phase for which the current is displayed.

Zone-selective	A number of circuit breakers are interconnected one after another by a pilot wire. In the event of a
Interlocking (ZSI)	short-time or earth fault:
	• If a given trip unit STR53UP detects the fault, it informs the upstream circuit breaker which applies
		the set time delay
	• If the trip unit STR53UP does not detect the fault, the upstream circuit breaker trips after its shortest
		time delay
	In this way, the fault is cleared rapidly by the nearest circuit breaker. In addition, thermal stresses on
	the circuits are minimized and time discrimination is maintained throughout the installation.
Opto-electronic	The use of opto-transistors ensures total isolation between the internal circuits of the trip unit and the
Outputs	circuits wired by the user.
Communication	Transmission of the following data to Digipact® distribution monitoring and control modules:
(COM)	•	Settings
	• Phase and neutral currents (rms values)
	• Highest current of the three phases
	•	Overload condition alarm
Possible	•	I
Combinations	•	T
	•	I + T
	•	I + COM
	• I + T + COM
	•	ZSI
	•	ZSI + I
	•	ZSI + T

• ZSI + I + T

• ZSI + I + COM

• ZSI + I + T + COM

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