Omega DPF78, DPF76, DPF75 manual Analog Output Option, Description

ANALOG OUTPUT OPTION

Description:

An optional 4-20mA (0-20mA) output has been added to the DPF70 series. The output can be programmed to track rate or total. This feature is available by adding suffix A to the part number. Connec- tions are via a 2 terminal pluggable screw connector.

Connections: (see FIG. 1)

PIN13 supplies the 12 to 18 VDC to power the current loop. PIN14 is the control sink driver

Accuracy: 50uA worst case

Compliance Voltage:

3 to 30 VDC non conductive

Setup:

The optional analog output feature uses 4 dip switches on the back for setup. These switches are used as follows:

SW1 - View or change "set low" and/or "set high" values SW2 - Select output for rate or total

SW3 - Select 4-20mA or 0-20mA SW4 - Calibrate the unit.

After the regular parameters shown in the programming flowchart have been set, locate the 4 switches on the back of the unit. (see FIG. 1)

Switch Settings:

SWITCH 1: Enter Analog Low & High (normally off)

Switch 1 is used to load in the low (4mA or 0mA) and/or the high (20mA) output settings. With power on, set switch 1 ON (up).

LOW SETTING is viewed or changed by pressing PRE A. If the displayed value is correct, press ENTER. If not, press buttons A through E to step to the desired value and press ENTER. (disre- gard the display which will show the last count reading).

HIGH SETTING is viewed or changed by pressing PRE B. If the displayed value is correct, press ENTER. If not, press buttons A through E to step to desired value and press ENTER.

Return switch 1 to OFF (down) position, PRE A and PRE B buttons now function to view or change relay trip values.

SWITCH 2: Select Count or Rate

SW2 OFF (down): Analog output follows rate

SW2 ON (up): Analog output follows count

SWITCH 3: Select 4-20mA or 0-20mA

SW3 OFF (down): Selects 4-20mA output range

SW3 ON (up): Selects 0-20mA output range

SWITCH 4: Calibrate (normally off)

Switch 4 is used for calibration. Calibration is done at the factory and should not be needed (see SWITCH 1 to enter high and low values). If recalibration is desired, a calibrated 20mA ammeter with 1uA resolution is needed. Attach the "+" lead of the meter to pin 13 and the "-" lead to pin 14. Set switch 4 ON (up). The unit will output approximately 20.000mA and a decimal will light in the third position. Read the output using the ammeter. Press PRE A. If the display is the same as the ammeter reading, press ENTER. If not, press buttons A through E to step to ammeter reading and ENTER. (Disregard display which now shows the last count read- ing with decimal point in third position) Return switch 4 to OFF (down) position.

RS232 & RS422 Operation:

When the unit is suppled with RS232 or RS422, the analog output "low" and "high" settings can be accessed and changed through the serial port. The codes are as follows:

AL Unit will display (transmit) analog out "low" value. AL(S)XXXXX Unit will load analog out "low" with entered

number. (S) = space

AH Unit will display (transmit) analog out "high" value. AH(S)XXXXX Unit will load analog out "high" with entered

number. (S) = space

FIG. 1

Analog Out				Serial Port				Setup Switches
13	14								4	3	2	1
												ON
			REAR			VIEW
1	2	3	4	5	6	7	8	9	10	11 12

Typical Wiring:

RELAYA	COM.	1
RELAYA	N.O.	2
RELAY B	COM.	3
RELAY B	N.O.	4	PULSE OUTPUT
INPUT A		5
INPUT B		6	+12V
11 to 19V @50mA OUT/ +DC IN		7
			GND
-DC (GROUND)		8
RESET INPUT		9
6 to 14V @ 50mA 10
110 / 220 VAC		11	TURBINE FLOWMETER
110 / 220 VAC		12
11 to 19V OUT 13			+
ANALOG OUT (SINK) 14			-

STRIP CHART

RECORDER

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