ABB TZIDC, Руководство пользователя

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TZIDC DIGITAL POSITIONER | DS/TZIDC-EN REV. G 3
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Brief description
The TZIDC is an electronically configurable positioner with
communication capabilities designed for mounting on
pneumatic linear or rotary actuators. It features a small and
compact design, a modular construction, and an excellent
cost-performance ratio.
Fully automatic determination of the control parameters and
adaptation to the positioner allow for considerable time
savings as well as optimum control behavior.
Pneumatics
An I/P module with subsequent pneumatic amplifier is used
to control the pneumatic actuator. The well-proven I/P
module proportionally converts the permanent electrical
setpoint signal from the CPU into a pneumatic signal used to
adjust a 3/3-way valve.
Dosing of the air flow for pressurizing or depressurizing the
actuator is continuously adjusted. As a result, excellent
control results are achieved. When reaching the setpoint, the
3/3-way valve is closed in center position to minimize the air
consumption.
The pneumatic system can be supplied in four versions: for
single acting and double acting actuators and each with the
‘fail-safe’ / ‘fail-freeze’ safety function.
‘Fail-safe’ safety function
If the electric power supply fails, the positioner output 1 is
depressurized and the return spring in the pneumatic
actuator moves the valve to the safe position. In case of a
‘double-acting’ version, output 2 is additionally pressurized.
‘Fail-freeze’ function
If the electric power supply fails, the positioner Output 1
(and Output 2 if applicable) is closed and the pneumatic
actuator blocks the valve in the current position. If the
compressed air supply power fails, the positioner
depressurizes the actuator.
Use
The positioner has a built-in operating panel providing a 2-
line LCD indicator and 4 operating buttons for
commissioning, configuration and monitoring during live
operation.
Alternatively, the appropriate configuration program can be
used via the available communication interface.
Communication
The positioner has a local communication interface (LCI) as
standard. Additionally, a ‘HART® communication’ option for
communication via the 20 mA signal is available. Both
communications are based on the HART® Protocol.
Alternatively, HART®5 or HART®7 are available.
Inputs / Outputs
In addition to its input for the analog position setpoint, the
positioner is equipped with a digital input which can be used
to activate control system functions in the device. A digital
output allows you to output collective messages (alarms /
faults).
Modular design
The basic model can be enhanced at any time by retrofitting
optional equipment.
Option modules can be installed for analog and digital
position feedback.
Additionally, a mechanical position indicator, proximity
switches or 24 V microswitches are available for indicating
the position independently of the mother board function.