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Reference Manual

00809-0100-4811, Rev DA

Section 4: Basic Configuration/Start-Up

January 2015

Basic Configuration/Start-Up

4.4.13 4 and 20 mA points

When setting the range values, it is possible to enter the values directly using the keypad on the

Field Communicator, or you may use actual values (HART command [1, 3, 4, 2]). Keep in mind

that the 20 mA value must be below the upper transition zone. If the 20 mA point is set to a

point within the Transition Zone, the full range of the analog output is not used.

Make sure the 20 mA value is below the Upper Null Zone (UNZ). (This parameter can be used if

there are measurement problems in the upper part of the tank, see Disturbances at the top of

the tank on page 102). The UNZ is equal to zero in the default configuration.

The 4 mA point must be above the lower transition zone. If the 4 mA point is set to a point within

the transition zone or below the probe end (tank bottom for example), the full range of the

analog output is not used.

See Transition zones on page 16 for more information on the size of upper and lower transition

zones.

Figure 4-7. Range Values

HART Comm

1, 3, 4, 3

20 mA Upper Range Value (URV)

Upper transition zone

Product level

Interface level

Lower transition zone

4 mA Lower Range Value

(LRV)

Upper reference point

Range 0-100 %

1 2 ... 78 79 80 81 82 83 84 85 86 87 88 ... 223 224

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