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VEGA PLICSCOM User Manual

Page 22

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22

5 Setup - Sensors up to software 3.99

PLICSCOM •

36433-EN-130228

Current output

Characteristics

4 … 20 mA
20 … 4 mA

Failure mode

4)

Hold value
20.5 mA
22 mA
< 3.6 mA

Min. current

5)

3.8 mA
4 mA

Max. current

6)

20 mA
20.5 mA

The values in bold font represent the data of the factory setting.
In HART multidrop mode, the current is constantly 4 mA. This value

does not change even in case of failure.

Current output

Characteristic: 4-20 mA

Failure mode: 22 mA

Min. current 3.8 mA

The functional safety is already activated Ex factory for instruments

with SIL qualification. For instruments Ex factory without SIL qualifica-

tion, the functional safety must be activated by the user for applica-

tions according to SIL via the indicating and adjustment module. The

SIL factory setting cannot be deactivated by the user.
The activation of SIL has the following impact:

In the menu item "Failure mode" under "Current output", the

parameters "Hold value" and "20.5 mA" are blocked

In the menu item "HART mode", the function "Multidrop" is blocked

Note:

For such applications, it is absolutely necessary to take note of

"Safety Manual".

HART offers standard and multidrop mode.
The mode standard with the fixed address 0 means output of the

measured value as 4 … 20 mA signal.
In Multidrop mode, up to 15 sensors can be operated on one two-wire

cable. An address between 1 and 15 must be assigned to each sen-

sor.

7)

In this menu item you determine the HART mode and enter the ad-

dress for multidrop.

Service/Functional safety

(SIL)

Service/HART mode

4)

Value of the current output in case of failure, e.g. if no valid measured value is

delivered.

5)

This value is not underrun during operation.

6)

This value is not exceeded during operation.