Baelz Automatic BA 7020, Operating Instructions Manual

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Operating Instructions BA 7020
Technical specifications subject to change without notice Copyright according to ISO 16016
BA_7020_00_EN_MJ_4917
6.7 Operational modes and operating options
6.7.1 Standard operation using DIP switches
The DIP switches can be used to carry out standard configurations and operations (see Fig. Fig. 6 page 13).
When DIP switch 11 is set to 0, the 7020 is in the standard operational mode.
In standard mode, all DIP switches are active and the functions of the Baelz 7020 can be individually adapted.
Functions which are predefined and unalterable in standard mode are described in chapter 6.1.
6.7.2 Standard operation using Modbus VT100 or direct addressing
In standard mode, the Baelz 7020 can be operated using Modbus VT100. For this, a virtual 7020 display and a
virtual 7020 keypad are transmitted to a user interface. Modbus direct addressing, e.g. from a building automation
system, enables access to status information and allows operation and configuration. (See appendix A). The
settings given by the DIP switches remain active. Values which are only relevant in Modbus mode can be adjusted
in standard mode, but only take effect in Modbus mode.
6.7.3 Modbus mode
When DIP switch 11 is set to 1, the Baelz 7020 is in Modbus mode. In Modbus mode, the 7020 is at its most
flexible and can be configured and operated using either a Modbus VT100 or Modbus direct addressing, for
example in a building automation system. See separate operating instructions "Baelz 7020 Digital Positioner -
Operating Instructions for Modbus mode"
6.8 Normal and safety modes
In normal mode the position of the valve is controlled by the set value at analogue
input AI2. The N↔S switch shown in the picture on the right is set to normal
mode (N). In normal mode, no external control systems can be connected to
terminals 12 and 14.
6.8.1 Safety mode: antifreeze und excessive temperature
In safety mode the actuator can be sent to a safe position (extended / retracted,
depending on the direction of action of the valve) in case of failure or malfunctioning of the microcontroller.
To operate the Baelz 7020 in connection with an external antifreeze and/or excessive temperature thermostat, set
the N↔S switch to safety mode (S).
Connect the antifreeze and/or excessive temperature thermostat according to desired function and priority. Be sure
to take the direction of action into account! See wiring diagrams in chapter 10.1.
terminal 12
terminal 14