Teledyne 4220 installation and operation guide Analog Output

4220 Flow Meter

Section 2 Programming

or two current loops supplied. If you use both the external con- verter and the internal board, you can have a total of four current loops controlled by the same flow meter. The internal current loops are brought out to a 6-pin M/S connector in the slot where the Modem connector is usually mounted.

To activate the internal analog output(s), return to the main screen and press 4, 2, 0.

ANALOG CAPABLE (‘0’ TO DISABLE)

OUTPUTS 3❚ (‘EXIT PROGRAM’ WHEN DONE

Additional information for the internal analog output board, including specifications for the loops, is found in Section 5.3.2.

CAUTION

Each 4-20 mA output represents a constant draw on the flow meter of at least 16 mA, whether activated or not. While 4-20 mA applications are generally made in installations with com- mercial power available, Teledyne Isco suggests the following for those who have a 4-20 mA output in a battery-powered installation.

Use with battery powered flow meters only if:

•The battery is continuously on charge (for example with a Solar Panel Battery Charger).

•The battery is very large, such as a deep-cycle or marine type battery, or an Isco 35 Ampere-hour lead-acid battery.

•Use only one 4-20 mA output.

•Keep in mind that programming choices also affect power consumption. Use “minimum” settings on the flow meter wher- ever possible. (See Section 1, Table 1-5.)

Even with these circumstances, you may expect significantly shorter charge life from your battery. To determine the effect of this extra current draw on battery life, please refer to the sec- tion How to Make Battery Calculations, at the end of Section 1.

The following menus determine the behavior of the 4-20 mA current outputs. If you select ANALOG OUTPUT (another term for the 4-20 mA Output) and the flow meter is equipped with the optional internal board or the 4-20 mA external accessory has been turned on, RANGE, SMOOTHING, and MANUAL CONTROL will appear:

ANALOG OUTPUT

• EXTERNAL 4-20 MA • • (RANGE) • • (SMOOTHING) • •

CAUTION

If you do not have the proper hardware installed and you press 4 - 2 - 0, and the number of analog outputs is not zero, the external 4-20 mA converter will not work properly. If this

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