Met One E-BAM, Руководство по эксплуатации

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E-BAM-9805 Manual Rev B.docx Page 55
Problem:
The airflow won’t regulate at the correct rate of 16.7 lpm.
Cause/Solution:
•
This usually indicates that the air pump is losing vacuum capacity due to wear.
•
Check for leaks at the nozzle. This will often cause the inlet flow to be low even
though the flow sensor is measuring the correct flow rate. This is because the flow
sensor is downstream of the filter tape and nozzle. Clean the nozzle and vane.
•
Perform a flow calibration. If the flow regulates at the lower calibration point, but not
the higher point, the pump is probably worn out or there is a leak.
•
The grey plastic pump muffler used on the vacuum pump clogs up after several
months. Replace it every six months.
•
Check the inlet and PM heads for obstructions.
Problem: The mass monitor has flow leaks, even after cleaning the nozzle and vane.
Cause/Solution:
•
The nozzle may be sticking. Verify that the nozzle up/down motion is smooth
and complete. If the movement is sticky or gritty, it will not seal properly.
•
Check the O-rings on the sharp-cut cyclone (if used). These frequently leak.
•
Check for bad O-rings on the inlet receiver.
•
Check all of the push-in air fittings throughout the air flow system.
Problem: The mass monitor will not pass the span membrane test.
Cause/Solution:
•
This often just indicates the membrane foil surface is dirty or damaged. It can be
cleaned with distilled water. Damaged membranes must be replaced.
•
If the membrane is in good condition, but the mass monitor fails span tests, then the
most common problem is debris on the beta detector window. Carefully blow
through the vane with canned dusting air to blow debris off of the detector window
and try again.
•
If the detector is clean and the membrane is in good condition, then failed span tests
can indicate that the detector is wearing out. Contact the Service Department.
Problem: The clock settings are lost when the mass monitor is powered down.
Cause/Solution:
•
There is a lithium coin cell battery inside the mass monitor that maintains the clock
when the mass monitor is powered off. The battery may need to be replaced if the
clock resets when the mass monitor is powered off.