Siemens LC 500 사용자 설명서
Page 94
SITRANS LC 500 – INSTRUCTION MANUAL
7ML19985GE01
mmm
mm
Appendix E
Application: Analog fault signalling (2-state output)
In 2-state mode, the loop current signals whether the probe is covered or uncovered, and
the continuous level measurement is unavailable.
the continuous level measurement is unavailable.
2-state mode provides:
• a 4 mA or 20 mA output to menu 07, when the level reaches one of the threshold
settings
• a 3.6 or 22 mA output to menu 07 (if 2-state fault signalling is enabled at menu
08) when the process level exceeds one of the limit settings (menu 0B and 0C).
The above settings can be modified:
• The response time when thresholds are reached can be modified by Upper and/
• The response time when thresholds are reached can be modified by Upper and/
or Lower Threshold delays (menus 03 and 04).
• The mA reading can be stabilized if necessary by applying Damping (menu 0A):
the increment value is controlled at menu 09.
Example:
Device settings:
(The device is first restored to factory settings before being commissioned)
TV0 selected: Transmitter Variable 0 is PV
(The device is first restored to factory settings before being commissioned)
TV0 selected: Transmitter Variable 0 is PV
Menu 01 reads Pv = 0
Lower Range Value (0% of range) is set to 14.3
Menu 0E reads 14.30
Upper Range Value (100% of range) is set to 75.8
Menu 0F reads 75.80
Current loop is in 2-state mode (C: Hi selected)
Menu 07 reads C:Hi
2-state fault signalling enabled (F: Hi selected
Menu 08 reads F:Hi
1
Activation hysteresis is set to 90
Menu 05 reads 90.0
Deactivation hysteresis is set to 8
Menu 16 reads 08.0.
1.
F: Hi appears while the button is pressed. See
on
page 66 for more details.
P
current loop connection
(menu 0F) URV = 100%
Upper Threshold Level = 90%
menu 05 (activation hysteresis)
menu 06 (deactivation hysteresis)
Lower Threshold Level = 8%
Menu 0E LRV = 0%
(menu 0C) USL
Menu 0B LSL
2-state
output
(menu 07)
Current activated relay module
75.8 pF
14.3 pF
83.5pF
7.3 pF
Active Shield section