Teledyne 4220 installation and operation guide mA Output Interface Specifications

			4220 Flow Meter
		Section 5 Options and Accessories
	mation from the flow meter to a variable analog output current
	ranging from 4 to 20 milliamperes. When a condition measured
	by the flow meter is converted into an analog output, 4 mA
	becomes the 0% or baseline for the condition, while 20 mA
	becomes the 100% or full-scale of the condition. Teledyne Isco
	offers two different arrangements for providing the 4-20 mA
	outputs. One is an external box that converts the signals from
	the flow meter to a 4-20 mA current loop. The other is an internal
	circuit board containing from one to three separate analog output
	circuits on the same board.
	The 4 to 20 mA current is an industrial standard current loop for
	process control equipment that must respond to changing condi-
	tions by varying output rates.
5.3.1 External Analog	The External 4-20 mA Output Interface has its own case and AC
Output Interface	power supply. Commercial power (120 VAC) must be available
	for this device. Battery operation (12 VDC) is not feasible due to
	voltage and current demands. It comes with a line cord, con-
	nectors, and two interconnect cables. One cable has 6-pin M/S
	connectors on both ends. This cable connects the input of the 4-20
	mA Output Interface to the flow meter Interrogator connector.
	The other cable has a three-pin plug on it that connects to the
	output connector of the 4-20 mA Output Interface. This cable
	ends in three pigtailed wires you connect to the equipment you
	want to control with the 4-20 mA Output Interface.
	Table 5-1 4-20 mA Output Interface Specifications
	Power	120 VAC	1⁄8 Amp.
	Output Connector	3-pin male plug
		Pin A: + current out
		Pin B: – current out
		Pin C: not used
	Output Accuracy:
	At 72° F (22°C)	±0.25% of full-scale
	Full Oper. Range	±0.5% of full scale
	Operating Temperature Range	0° to 140°F (–18° to 60°C)
	Resolution	0.1% of full-scale
	Input Connector	6-pin male M/S
		Pin B: – pulse input
		Pin F: + pulse input
		Pins A, C, D, E: NC
	Isolation	Output current optically isolated from
		flow meter.
	Fusing	1⁄4 Amp. internal on AC line.

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