Hach 900 MAX 4–20mA Option, 6.3.1, 4–20mA Connection, 6.3.2 4–20mA Programming, Section, Rating

Section 6

6.3	4–20 mA Option
		The 4–20 mA option provides a current loop for controlling external devices
		such as a chart recorder or PC. Either one or both of the 4–20 mA outputs can
		be factory installed and are isolated from each other.
6.3.1	4–20 mA Connection
		The interface has a 3-ft cable with a connector on one end, and a 10-ft cable
		with two open wire leads on the other. Insert the connector into the sampler
		receptacle labeled “Auxiliary”, located on the left side of the control housing.
		On the 10-ft cable, the wire with clear insulation is positive (+) and the wire
		with black insulation is negative (-).
		Table 16 4–20 mA Connections (J18)
	Pin	Signal Description	Wire Color
	A	Output 1 + (pos)	Yellow
	B	Output 1 - (neg)	Black
	C	Output 2 + (pos)	Red
	D	Output 2 - (neg)	Green

Rating:

•Isolation Voltage:

Between sampler and either 4–20 mA output: 2500 V ac

Between the two 4–20 mA outputs: 1500 V ac

•Maximum Resistive Load: 600 ohm

•Output Voltage: 24 V dc - no load

Cable Required

4–20 mA Interface Cable (Cat. No. 2924), 25 ft long, 4-pin connector on one end, tinned wire leads on the other end.

6.3.2 4–20 mA Programming

Note: When the 4–20 mA outputs are disabled and not completely turned off, they will continue to output a steady 4 mA.

1.From the Main Menu, select OPTIONS > ADVANCED OPTIONS > 4–20 mA

OUTPUTS > SELECT.

2.Enable the 4–20 mA outputs by pressing CHANGE CHOICE while in the 4–20 mA output menu.

3.When the display shows the outputs as enabled, press ACCEPT.

4.Choose either OUTPUT A or OUTPUT B. Use the UP and DOWN keys to highlight the choice, then press SELECT.

11:00 AM 21 - APR - 01		4–20 mA OUTPUTS
SELECT	OUTPUT A
	OUTPUT B

RETURN

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8990cm.fm	4–20 mA Option