Xylem FT420 RATE/TOTAL INDICATOR - Manual (Page 12)

LT-65200063-D
9/20/10
Seametrics Incorporated • 19026 72nd Avenue South • Kent, Washington 98032 • USA
(P) 253.872.0284 • (F) 253.872.0285 • 1.800.975.8153 • www.seametrics.com
TROUBLESHOOTING
Problem Probable Cause Try...
Display blank No power to the unit Check for minimum 12 Vdc at power
terminals
Short in sensor circuit Disconnect sensor, see if display returns
(zero flow rate)
Battery dead or loose (FT415 only) Wiggle battery, replace if over three years old
Display missing segments Damaged display module Contact distributor for return/replacement
Display reading meaningless Unit’s microcontroller crashed Disconnect and reconnect power, if problem
characters repeats, contact distributor for
return/replacement
Battery nearly dead Replace battery if over three years old
Display reads normally, Wrong K-factor or time base entered Enter correct K-factor from meter, fitting, or
flow rate incorrect manual
Display reads normally, Wrong pulse output setting Use “Set P” to correct pulse output setting
incorrect pulse output
Polarity reversed on pulse output terminals Reverse leads
Display reads normally, but Wrong 20 mA setting Use “Set 20” to correct target top flow rate
no (or incorrect) 4-20 mA output
(FT420 only)
Inadequate loop power supply voltage Check voltage (For 4-20 mA applications,
24 Vdc recommended)
Polarity incorrect in 4-20 mA loop circuit Compare to Connections diagram
Display reads zero when Flow sensor failed Consult flow sensor manual for how to test
there is flow
Break in flow sensor circuit Check for continuity with multimeter
Flow sensor not battery-compatible Check flow sensor model number for
“micropower option”
Display reads flow rate when Long flow sensor wire, running parallel to Reroute wire or change to shielded wire
there is none power wires
Flow sensor malfunction See flow sensor manual to check
Flow “jitter” (oscillating slosh) reads as flow Consult factory for “anti-jitter” setting