ABB TZIDC-220, Operating Instructions Manual

Page: 38 / 71

38 Electro-pneumatic positioner TZIDC-220 42/18-82 EN
4.3 Options
Module for the shutdown function
Supply voltage 24 V DC (20...30 V DC)
(electrically isolated from the input signal)
Safe position is activated when voltage < 5 V
AK approval AK 4 to DIN V 19250
Test report No. 101/S01/148
Explosion protection see chapter "Certificates" starting on page 40
A separate 24 V DC signal is normally applied to the shutdown module, which connects th-
rough the signal from the microprocessor to the I/P module. When the 24 V DC signal is in-
terrupted, the I/P module executes the respective safety function, depending on the mecha-
nical construction.
Fail safe:
The positioner output 1 is depressurized, and the valve moves to the safe position. In case
of a double-acting actuator the second output is additionally pressurized.
Fail-freeze:
The pneumatic ouput 1 is closed, and the valve “freezes” in its current position. In case of a
double-acting actuator both outputs are closed.
The shutdown module works independently of the mother board, i.e. all information from the
final control element is available in the supervisory process control system at any time.
Digital position feedback with proximity switches
1
2 proximity switches for independent position signaling.
Switching points adjustable between 0 and 100 %
Current circuits to DIN 19234 / NAMUR
Supply voltage
5...11 V DC
Signal current < 1 mA logical "0"
Signal current > 2 mA logical "1"
Direction of action (logical state):
1.
The ’digital position feedback’ option is directly actuated by the rotating shaft of the
positioner and can only be used together with the (optional) mechanical position
indicator.
Proximity switch Position
< Lim. 1 > Lim. 1 < Lim. 2 > Lim. 2
SJ2-SN (NC) 0 1 1 0
SJ2-S1N (NO) 1 0 0 1
!
NOTICE
When using proximity switch type SJ2-S1N (NO) the TZIDC-220 positioner
may be exposed to an ambient temperature of -25 °C ... +85 °C, only.