Emerson Comprehensive Guide to E2 Controller and RS485 Failsafe Biasing Setup

6	1.	Connect the 4AO board to the RS485 I/O Network.
	2.	Set the network address on the first five
	rockers of dip switch S1.
	3.	Set the network baud rate using rockers 6
	and 7 of dip switch S1.
	4.	Set RS485 termination jumpers UP (terminated) if at
	either end of a daisy chain. Otherwise, set
	jumpers DOWN (not terminated).
	5.	Optionally, connect the 4-20mA outputs in either a 2-wire
	or 4-wire hookup as illustrated in Step 5, or if a 4-20mA is
	not used, it may be left unconnected.
	6.	Connect board to the 24VAC center-tappedsecondary
	of the power transformer.
	CAUTION: If you change any dip switch		VIN+
	settings while the board is powered, disconnect
	the power and re-power the board to reset.		15-K
	NOTE: The voltage divide function capability

	on the previous model (P/N 810-3030) 4AO board is				VOUT +
	no longer supported. This can now be accomplished		15-K
	by using two external 15-K resistors. If used with E2,
	scale output range.	-		-
SHIELDED TWISTED PAIR		BAUD RATE
BELDEN #8761. FOR PLENUM,
USE BELDEN #82761 OR #88761
OR EQUIV.

NET

I/O

WIRE + to + (same color)

WIRE 0V to 0V

WIRE - to - (same color)

J9 J10 J11	J9 J10 J11
		(Term)	(Term)
(Terminated)	(Not Terminated)

		“2-wire” 4-20mA
4-20mA		(Externally Powered)
Analog		Hookup example.
Output		(Isolated)
	+12V	Not Used			24V
	+4-20		+
	4-20 OUT	_
	0V	Not Used
				250 ohms	1-5V

		4-20mA					“4-wire” 4-20mA
							(Internally Powered)
		Analog
							Hookup example.
		Output
							(Not Isolated)
+				Jumper
			+12V
_
			+4-20
			4-20 OUT			+
			0V		_			250 ohms	-5V
	Note:
	Either the “2-wire” or “4-wire”
	Hookup may be used at either
								Grounded
	4-20mA output. The Hookups may
	be the same or different. If a 4-20mA

is not used, it may be left unconnected.

6 WIRING FOR 640-0056, 56VA Transformer, and 640-0080, 80VA Transformer

24VAC Center-Tapped Transformer

Power Wiring Types:

14 AWG	Belden 9495
18 AWG	Belden 9493

120/208/240 VAC

L2	(HOT)	(NEUTRAL)
		L1

240	208	C
		120

PRIMARY SIDE

Three-conductor non-shielded cables	AC1
are the recommended wire
for connecting between the	0V
center-tapped transformer	AC2

and I/O boards.

AC1	0V	AC2
24V	CT	24V

SECONDARY SIDE

ECT MODBUS The RS485 Network and Hardware Setup • 6-15