Hydronix Hydro-Probe Configuration And Calibration Manual page 44

Chapter 5
Symptom: Incorrect Analogue Output
1.2
Possible
explanation
Wiring problem
Sensor's analogue
output is faulty
PLC analogue input
card is faulty
Symptom: Computer Does Not Communicate with the Sensor
1.3
Possible
explanation
No power to sensor
RS485 incorrectly
wired into converter
Incorrect serial Com
Port selected on
Hydro-Com
More than one
sensor has the same
address number
44 Configuration and Calibration Guide HD0679 Rev 1.2.0
Check Required result
Wiring at the Twisted pairs used
junction box and for complete length
PLC of cable from sensor
to PLC, is wired
correctly
Disconnect the Milliamp reading
analogue output within the normal
from the PLC and range (0-20mA, 4-
measure with an 20mA)
ammeter
Disconnect the Milliamp reading
analogue output within the normal
from the PLC and range (0-20mA, 4-
measure the 20mA)
analogue output
from the sensor
using an ammeter
Check Required result
DC power at +15Vdc to +30Vdc
junction box
Converter's wiring RS485 converter
instructions and A correctly wired
and B signals are
the correct
orientation.
Select correct Com Switch to the correct
Port on Hydro- Com Port
Com.
Connect to each Sensor is found at
sensor individually an address.
Renumber this
sensor and repeat
for all the sensors
on the network
Sensor Diagnostics
Action required on
failure
Wire correctly using
specified cable in
the technical
specification
Connect sensor to a
PC and run Hydro-
Com. Check
analogue output on
the diagnostics
page. Force the
mA output to known
value and check
this with an
ammeter
Replace analogue
input card
Action required on
failure
Locate fault in
power supply/ wiring
Check PC Com port
settings
Determine the Com
Port number
assigned to the
actual port by
looking at the PC
device manager
Try an alternative
RS485-RS232/USB
if available