User's Manual

4/00 UDC 3300 Controller Product Manual 33

Transmitter power for

4-20 mA 2-wire

transmitter—auxiliary

output

The wiring diagram example shown in Figure 2-20 (Model

DC330X-XX-2XX or DC330X-XX-5XX) provides 30 Vdc at terminal 16

with the capability of driving up to 22 mA, as required by the transmitter

which is wired in series.

If the transmitter terminal voltage must be limited to less than 30 volts,

you can insert a zener diode between the positive transmitter terminal and

terminal 16. For example, an IN4733A zener diode will limit the voltage

at the transmitter to 25 Vdc.

Configure:

AUX OUT = OUTPUT

Calibrate the Auxiliary Output using the procedure given in Section 8.4 –

Auxiliary Output Calibration.

ZERO VAL = 4095

SPAN VAL = 4095

Figure 2-20 Transmitter Power for 4-20 mA 2-wire Transmitter Using Auxiliary Output—

Model DC330X-XX-2XX or DC330X-XX-5XX

24172

L2/N

–

2-wire

Transmitter

250 ohm

resistor

–

If necessary, install zener

diode here to reduce

voltage at transmitter.