User Guide

Teledyne API M100E Analyzer Operation Manual Troubleshooting & Repair
263
12.3. GAS FLOW PROBLEMS
The standard M100E has one main flow path. With the IZS option installed, there is a second flow path flow path
through the IZS oven that runs whenever the IZS is on standby to purge SO
2
from the oven chamber. The IZS
flow is not measured and is not available from the front panel. The full flow diagrams of the standard
configuration (refer to Figure 3-4) and with options installed (refer to Figure 5-3 and Figure 5-4) help in
trouble
s
hooting flow problems. In general, flow problems can be divided into three categories:
 Flow is too high
 Flow is greater than zero, but is too low, and/or unstable
 Flow is zero (no flow)
When troubleshooting flow problems, it is essential to confirm the actual flow rate without relying on the
analyzer’s flow display. The use of an independent, external flow meter to perform a flow check as described in
Section 12.5.2 is essential.
12.3.1. ZERO OR LOW SAMPLE FLOW
If the pump is operating but the unit reports a XXXX gas flow, do the following three steps:
 Check for actual sample flow
 Check pressures
 Carry out a leak check
To check the actual sample flow, disconnect the sample tube from the sample inlet on the rear panel of the
instrument. Ensure that the unit is in basic SAMPLE mode. Place a finger over the inlet and see if it gets sucked
in by the vacuum or, more properly, use a flow meter to measure the actual flow. If a proper flow of
approximately 650 cm³/min exists, contact customer service. If there is no flow or low flow, continue with the next
step.
Check that the sample pressure is at or around 28 (or about1 in-Hg-A below ambient atmospheric pressure).
12.3.2. HIGH FLOW
Flows that are significantly higher than the allowed operating range (typically ±10-11% of the nominal flow)
should not occur in the M100E unless a pressurized sample, zero or span gas is supplied to the inlet ports. Be
sure to vent excess pressure and flow just before the analyzer inlet ports.
When supplying sample, zero or span gas at ambient pressure, a high flow would indicate that one or more of
the critical flow orifices are physically broken (very unlikely case), allowing more than nominal flow, or were
replaced with an orifice of wrong specifications. If the flows are more than 15% higher than normal, we
recommend that the technician find and correct the cause of the flow problem,
04515F DCN6048