Viatran IDP10-A, Инструкция по установке, калибровке и эксплуатации

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98MANALIDP10AV Rev. A 8/16/11
Transmitter Wiring for IDP10-V (1-5 VDC Output Signal)
The field terminals on a transmitter with a 1 to 5 V dc output signal are shown in Figure 13.
The transmitter is equipped with an internal ground connection within the field wiring
compartment and an external ground connection at the base of the electronics housing. To
minimize galvanic corrosion, place the wire lead or terminal between the captive washer and loose
washer on the external ground screw. If shielded cable is used, earth (ground) the shield at the
field enclosure only. Do not ground the shield at the transmitter.
Power Supply Voltage and Current
The power supply voltage across the transmitter input terminals can be any value between 9 and
15.5 V dc and the power supply must be capable of supplying 3 mA of current under all
conditions. Verify that the power supply loop load resistance and source impedance allow at
least 9 V dc across the transmitter input terminals with a current draw of 3 mA.
Output Load
The receiver input impedance can be any value between 1 and 10 M.
Three or Four Wire Connections
The transmitter is supplied with a four-wire terminal block with the two negative terminals (- and
B) electrically connected internally. This means that the transmitter can be wired with either three
wires for wiring economy or four wires for maximum accuracy.
For relatively short wiring runs having low resistance, three-wire connections as shown in
Figure 14 can be used to minimize wiring costs. However, a voltage drop in the common lead
carrying the power supply current causes an error in the 1 to 5 V dc signal.