AB-5963
10
Maintenance
Since the dewpoint temperature sensor is inspected and
calibrated for high accuracy at the factory before shipment,
no field calibration is necessary. Follow the maintenance
instructions below:
Periodic inspection
Periodically inspect the sensor for its sensing accuracy and
clean the cover. Set the period between inspections based
on atmospheric dust and other contaminants in the
installation environment.
Troubleshooting
If any problem occurs during operation, refer to the following
table for appropriate solutions.
Troubleshooting and solution
Problems Check
items
Solutions
•
No output
generated
•
Unstable
output
•
Loose wiring
•
Disconnected wiring
•
Power supply
voltage
•
Sensor damages
•
Tighten the terminal
block.
•
Re-perform wiring.
•
Replace the sensor.
•
Slow
response
to
output
•
Moisture/
condensation
on the sensor
•
Detach the main unit
from the bracket, and
remove the filter cap
and the filter.
Dry
power-off
state
sensor in clean air
seasoning.
•
Error in
output
•
Installed location
•
Dust and
contamination
on
the
sensor
•
Refer to the
‘Installation
requirements’.
•
Clean the filter.
•
Replace the filter.
•
Perform dewpoint
single-point
calibration.
•
Replace the sensor.
Filter replacement:
CAUTION
•
Installation must be performed by qualified
personnel in accordance with all applicable
safety standards.
IMPORTANT:
Be sure not to touch the print board or other parts
when they are not covered by the filter cap or the
filter.
1) Prepare the new filter set (with separate order required)
to replace with. Remove the old filter cap and filter (to
replace) by hand.
Figure 21. Filter cap removal
2) Before attaching the new filter, check that the rubber
packing sealing the sensing element is not raised from
the probe, as shown in Fig. 22.
Figure 22. Rubber packing position
For rubber packing raised, press it using a slotted
screwdriver as shown in Fig. 23.
Carefully handle the tool so as not to damage the
packing or other part of the product.
Figure 23. Pressing rubber packing
CAUTION
•
Carefully press the rubber packing. Personal
injury may result when your fingers holding the
tool slip.
Filter cap
(removed with the filter
inside the cap.)
Loosen.
Rubber packing:
not raised from the probe to
completely seal the element.
Rubber packing:
raised from the probe.
Sensing element may not
completely be sealed.
Sensing
element
Sensing
element
Press rubber packing using a
tool such as a slotted
screwdriver so that the raised
packing is placed back in
position.
Press