Endress+Hauser Liquisys M CCM223 - Page 57

Liquisys M CCM223/253 Commissioning
Endress+Hauser 57
measuring signal to be very sluggish or not even change at all (constant signal). This
passive behavior is detected and signaled by constantly monitoring the signal activity.
Overview of SCS monitoring functions
Mode of operation Possible
setting
Alarm event Use
Alarm threshold
monitoring
(P111 to P114)
(P121 to P124)
• User-definable lower
alarm threshold (AS)
• User-definable upper
alarm threshold (AS)
Off - Applications with
or without
chemical dosage
control
Only lower
alarm
threshold
Lower alarm threshold
reached or undershot
Only upper
alarm
threshold
Upper alarm threshold
reached or exceeded
Lower and
upper alarm
threshold
Lower alarm threshold
reached or undershot or
upper alarm threshold
reached or exceeded
Controller monitoring
(CC: controller check,
P115 to P118
P125 to P128)
• Switch-on duration
monitoring
• Switch-off duration
monitoring
Off - Applications with
chemical dosage
control
On Set maximum duration
for permanent switch-on
or switch-off exceeded
Sensor activity
monitoring
(AC: alternation
check,
P115 to P118
P125 to P128)
Signal change
monitoring
Off -
On Change within 1 hour
less than
• ±0.01 mg/l
(CCS140/240, sensor
963)
• ±0.005 mg/l
(CCS141/241)
• pH ±0.01
• ±1 mV
Applications with
or without
chemical dosage
control