Schneider Electric iFBZ, FBZ2, EOCR-i3BZ, 3BZ2 manual Standard connection

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Communication Guide

Standard connection

The standard connection conforms to the Modbus specifications, sepecially 2 wire multidrop serial bus diagram, presented at the website of Modbus.org in 2002 (Modbus_over_serial_line_V1.pdf, Nov.2002). Simple wiring diagram is like below.

The characteristics is like below in case of a direct connection to the bus.

	Items	Contents

	Type of trunk cable	single, shielded, twisted pair cable.
	Type of trunk cable	Min 3rd cable
		Min 3rd cable

	Maximum length of the bus	1000m (3,2181 ft) (at 19.2kbps)

	Maximum number of	32 stations (31 slaves)
	stations without repeater	32 stations (31 slaves)
	stations without repeater

		�20m (66ft, at 1 tapoff)
	Maximum length of tapoffs	�40m (131ft, divided by tapoff no.
		in Multi-Junction Box)

		�450 - 650Ω Pullup resistor, 5V basis
		�450 - 650Ω Pulldown resistor,
	Bus polarization	Recommend the polarization to Master at
		Common. There is no polarization at
		RS485 of EOCR .

	Line terminator	120Ω Resistor, + /- 5%

	Common polarity	YES (connect 1 protection ground minimum
	Common polarity	to the bus)
		to the bus)

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Contents Page Page Bottom hole & terminal type Applications Public institutions General Features EOCR-i3BZ/iFBZ/3BZ2/FBZ2Operating Condition & Setting Range Operation Time Protection functionsAuxillary functions Communication function Applicable to i3BZ/iFBZSpecifications Time-current characteristic curve Over current and time setting tips Over current Setting tips in definite TCC modeAlert Operation Pattern #3 Fail-safe operationBar graph Front faceCurrent display Button Description Phase digital ammeter functionButtons and Setting Sequence Setting sequence and menu Parameter DescriptionCommunication *2 Menu Parameter Description DefaultAlert *1 Trip cause indication and fault records Control terminalsWiring Examples Phase line DiagramSingle phase line Diagram Single line DiagramDimensions Order Code Modbus network setting RS485 bus connectionStandard connection Bus connection through a SCA type junction box Head Office Iksan Plant