Emerson 2400S 3.4.4Discrete input wiring, 2 Input voltage ranges for external power

I/O Wiring – Model 2400S Analog Transmitters

Figure 3-12Recommended pull-up resistor versus supply voltage – External power

	5200
	4800
	4400
	4000
(Ohms)	3600
range	3200
resistor	2800
	2400				Recommended
				resistor value range
pull-up
	2000
External	1600
	1200
	800
	400
	6	12	18	24	30	36

Supply voltage (Volts)

Note: When using a discrete output to drive a relay, choose external pull-up to limit current to less than 500 mA.

3.4.4Discrete input wiring

Discrete input wiring depends on whether you will use internal or external power. The following diagrams are examples of proper wiring for these configurations:

•Internal power – Figure 3-13

•External power – Figure 3-14

If external power is configured, power may be supplied by a PLC or other device, or by direct DC input. See Table 3-2for input voltage ranges.

Table 3-2Input voltage ranges for external power

VDC	Range
3–36	High level
0–0.8	Low level
0.8–3	Undefined

Before You Begin

Power Supply

I/O Wiring – AN

I/O Wiring – DP and DN

Installation Manual 19