Hydronix Hydro-Mix, Руководство по настройке и калибровке

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Sensor Diagnostics Chapter 5
Configuration and Calibration Guide HD0679 Rev 1.2.0 45
1.4
Symptom: Near Constant Moisture Reading
Possible
explanation Check Required result Action required on
failure
Empty bin or sensor
uncovered Sensor is covered by
material 100mm minimum
depth of material Fill the bin
Material stuck in bin Material is not stuck
above sensor Smooth flow of
material over the
sensor face when the
gate is open Look for causes of
erratic flow.
Reposition sensor if
problem continues
Build-up of material
on sensor face Signs of build-up
such as dried solid
deposit on ceramic
face Ceramic faceplate
should be kept clean
by the action of
material flow Check angle of the
ceramic in range of
30° to 60°. If problem
continues reposition
sensor.
Incorrect input
calibration within
control system Control system input
range Control system
accepts output range
of sensor Modify control
system, or
reconfigure sensor
Sensor in alarm
condition – 0mA on
4-20mA range Moisture content of
material by oven
drying Must be within
working range of
sensor Adjust sensor range
and/or calibration
Interference from
mobile phones Use of mobile
phones close to
sensor No RF sources
operating near to
sensor Prevent use within
5m of sensor
Average/Hold switch
has not operated Apply signal to digital
input Average moisture
reading should
change Verify with Hydro-
Com diagnostics
No power to sensor DC power at junction
box +15Vdc to +30Vdc Locate fault in power
supply/ wiring
No sensor output at
control system Measure sensor
output current at
control system Varies with moisture
content Check cabling back
to junction box
No sensor output at
junction box Measure sensor
output current at
terminals in junction
box Varies with moisture
content Check sensor output
configuration
Sensor has shut
down Disconnect power for
30 seconds and retry
or measure current
drawn from power
supply Normal operation is
70mA – 150 mA Check operating
temperature is within
specified range
Internal failure or
incorrect
configuration Remove sensor,
clean face & check
reading (a) with
ceramic face clean
and (b) with hand
pressed firmly on
ceramic face. Reading should
change over a
reasonable range Verify operation with
Hydro-Com
diagnostics