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5 Connecting to power supply
VEGAMET 861 • 4 … 20 mA/HART
58866-EN-200401
Warning:
In delivery status, all openings are fitted with dust protection caps.
These caps are only for protection during transport and are not suit-
able for protection during operation! Instead, all openings must be
closed with cable glands/blind plugs.
Cable glands, NPT adapters or blind plugs that are not included in
the scope of delivery must meet the applicable requirements in order
to ensure the environmental compatibility of the housing. For outdoor
applications, the weather resistance of the accessories to be used
must be taken into account. The cable glands, NPT adapters and
blind plugs must have a metric thread M20 to be compatible with the
threaded openings of the metal plate in the housing.
5.2 Sensor input mode active/passive
Through the selection of the terminals, you can choose between ac-
tive and passive operation of the sensor input.
•
In active mode, the controller provides the power for the con-
nected sensors. Power and measurement data are transmitted
over the same two-wire cable. This mode is provided for connec-
tion of measuring transducers without separate power supply
(sensors in two-wire version).
•
In passive mode the sensors are not powered, only the measured
value is transmitted. This input is for connection of transmitters
with their own separate voltage supply (sensors in four-wire ver-
sion). The VEGAMET 861 can also be looped into the existing
circuit like a normal ammeter.
Note:
With a VEGAMET 861 in Ex version, the passive input is not available.
5.3 Digital input mode active/passive
Through the selection of the terminals, you can choose between ac-
tive and passive operation of the digital input.
•
At the active input the controller provides a power supply. This
operating mode is intended for the connection of potential-free
switching contacts. An external voltage must not be supplied.
•
At the passive input a voltage must be supplied via the switch-
ing contact. This input is intended for the connection of switching
contacts with their own, separate power supply. The permissible
voltage specifications for this can be found in the technical data.
With the application "
Pump control
", the digital input can be used for
pump monitoring.
5.4 Connecting
The voltage supply and inputs and outputs are connected via the
spring-loaded terminals.
Cable glands
Connection technology
