PRODUCT INSTRUCTION SHEET
10.1 GENERAL MAINTENANCE. Service the sensor regularly
(weekly is suggested)
10.2 MEMBRANE CAP REPLACEMENT. If membrane replace-
ment is required, a new cap with preinstalled membrane must
be used. Order FCLA-2016 replacement membrane cap and
FCLA-2015 refill solution. To change membrane cap (do the
following over a sink or washbasin):
a) turn sensor upside down with cap facing upward
b) rotate cap counter-clockwise to remove (see FIG 10).
c) fill sensor body with electrolyte using needle and bottle of
refill solution (see FIG. 11)
d) install a new membrane cap by threading cap onto sensor
rotating cap clockwise (opposite of FIG 10)
10.3 MEMBRANE CAP/SENSOR CLEANING. Rinse cap with
water only. If cap does not clean, replace with new one.
SECTION 10.0
SENSOR MAINTENANCE/RECONDITIONING
SECTION 11.0
SENSOR TROUBLESHOOTING
11.1 CALIBRATION PROBLEMS
a) Sensor output
HIGHER
than DPD test
1) Run in time too short
2) Membrane cap damaged
3) Interference from water
contaminants (see Specifications,
"Cross Sensitivity")
4) Cable short circuit or damage
5) pH value less than pH 5.5
b) Sensor output
LOWER
than DPD test
1) Run in time too short
2) Deposits on Membrane cap
3) Flow rate too low
4) Air bubbles on membrane
5) Surfactants in water
6) pH value more than pH 8.0
7) No electrolyte in membrane cap
c) Sensor ouput is 4mA (zero ppm)
1) Run in time too short
2) Only bound chlorine present
3) Chlorine content below detection
limit
4) Sensor not wired correctly (See
SECTION 6.0 of this manual)
5)
Defective
sensor
d) Sensor output
UNSTABLE
1) Air bubbles on membrane
2)
Membrane
damage
3)
Non-sensor
problem
Symptom
Possible Cause
Solution/Remedy
The sensor
1) Run in time too short
1) See Sec 5.0 -CONDITIONING
cannot be
2) Membrane cap damaged
2) Replace cap - See Sec 8.0
calibrated-
3) Interference from contaminants
3) See SPECIFICATIONS
ouput is
4) DPD chemicals bad
4) Use new DPD kit
HIGHER than
5) pH value < pH 5.5
5) Increase pH (5.5-8.0)
DPD Test
See SPECIFICATIONS
6)Temperatue increased since cal
6) Match calibration temp.
The sensor
1) Run in time too short
1) See Sec 7.0 -CONDITIONING
cannot be
2) Deposits on membrane cap
2) Remove deposits or replace
calibrated-
cap if cleaning ineffective.
output is
3) Flow rate too low
3) increase fl ow - See
LOWER than
SPECIFICATIONS
DPD Test
4) Air bubbles on membrane
4) Remove and re-install sen
sor to remove bubbles.
5) Surfactants in water
5) Remove surfactants and
replace cap
6) pH > pH 8.0
6) Lower pH (5.5-8.0)
See SPECIFICATIONS
7) No electrolyte in cap
7) Add new electrolyte, run in
sensor and re-calibrate
8) Temperature decreased since cal 8) Increase temp to match cal
9) Organic chlorination agents
9) Use chlorinating agents
present in water
per DIN 19643
Sensor output
1) Only bound chlorine present
1) Check for Chloramine with
is 4mA (0 ppm)
NO FREE CHLORINE
appropriate DPD test.
Replace water/ Rechlorinate.
2) Run in time too short
2) See Sec 7.0 -CONDITIONING
3) Chlorine content below limit
3) Add chlorine and repeat
calibration
4) No electrolyte in cap
4) Refi ll electrolyte
5) Sensor electrical connection
5) See SECTION 6.0
wrong
Unstable output
1) Air bubbles on sensor membrane 1) Tap to remove bubbles
from sensor
2) Membrane damaged
2) Replace membrane, run in
sensor and recalibrate.
3) Non-sensor problem
3) check PLC or I/O device
TROUBLESHOOTING CHART
FIG. 10
INJE
C
T UNTIL
S
OLUTION
LEAK
S
OUT OF FILL HOLE
FIG. 11
Parts covered by this product instruction sheet include: FCLTX-100 Series
M4679/0708 page 5 of 6
