Operation Manual HORIBA APDA-371
Particulate Monitor
Date:
April, 2010
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HORIBA Europe GmbH, Julius-Kronenberg-Str. 9, D-42799 Leichlingen, Telefon: +49(0)2175-8978-0, Fax: +49(0)2175-8978-50
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7.3
Self-Test Feature
A primary method of identifying a hardware malfunction in the APDA-371 is the SELF TEST feature in the TAPE menu.
This can identify a large number of the possible mechanical failures in the unit, and is a good place to start if a problem
is suspected or if frequent errors are recorded. See Section 3.5 for a description of the self-test process.
7.4
Power-Up Problems
The APDA-371 must at least be able to power on before any further diagnosis can be performed. There are only a few
possible reasons that the unit will fail to power up:
•
Make sure that the unit is plugged into the correct AC voltage.
•
Check or replace the two fuses (3.15A, 250V) inside the power switch housing. The power cord MUST be
removed before the fuse door can be opened, or you will break it. Pry open the top edge of the power switch
housing cover to access the fuses.
•
It is possible for the display contrast to be set so light that it looks like the unit is OFF when it is really ON. Try
holding the contrast key for a few seconds. In rare cases the display may fail completely. If the unit “beeps”
when you press the keys, it is ON.
•
If the above checks are all OK, there could be a failed power supply inside the unit. Contact HORIBA for further
instructions. Do not attempt to open or repair the power supply assembly unless qualified.
7.5
Basic Problem and Cause/Solution Table
The following table contains information on some of the more common APDA-371 problems which may be
encountered, and some steps to identify and remedy the problems. HORIBA welcomes customer suggestions for new
items to include in this section of future manual revisions! If the solution cannot be found in the following table, then
contact one of our expert service technicians for help in resolving your problem.
Problem:
The APDA won’t start a measurement cycle.
Cause/Solution:
•
The unit is programmed not to start until the beginning of an hour. Make sure the
clock is set correctly.
•
The unit will wait until the beginning of a new hour before it starts, even if the
operation mode is set to ON.
•
Don’t expect the pump to turn on until the clean tape count is finished, either 4 or 8
minutes after the start of the hour.
•
The unit cannot start if the pinch rollers are latched UP! The unit cannot lower them.
•
Make sure the filter tape is installed correctly.
•
The unit will never start a cycle if the display is not on the main or OPERATE menu.
•
The unit will usually display an error and “beep” if it cannot start a cycle
Problem:
The analog output voltage and/or digital concentration reading are full-scale.
Cause/Solution:
•
The unit will force these values full-scale to indicate an error. Download the error
log. Whenever the unit is started or interrupted this will happen until the next hour.
Problem:
The concentration is reading negative values.
Cause/Solution:
•
It is possible for the unit to occasionally read negative numbers if the actual
particulate concentration is very low, such as below 3 micrograms. This is because
the APDA has a “noise band” of several micrograms. This should not happen often.
•
If the unit is reading negative numbers hour after hour, it is probably punching holes
in the filter tape. These holes can be very small and hard to see. This is almost
always caused by debris on the nozzle or vane. Clean the parts.
•
Make sure the SETUP > CALIBRATE values match the calibration sheet, especially
the BKGD value.
•
The BKGD value may need to be field-audited. HORIBA supplies the BX-302 zero
filter kit for auditing the zero reading of the unit.
Problem:
The airflow rate is too low and won’t adjust up to 16.7 lpm.
Cause/Solution:
•
The gray plastic pump mufflers clog up after several months. Replace it or drill a
hole in the end of it for a temporary fix. The brass mufflers can often be cleaned.
