Thermo Scientific SOLA II, User Manual

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Operation
Injection Valve Failure Alarm
Thermo Fisher Scientific SOLA II User Guide 5-3
Figure 5–3.
Over time, the injection valve begins to wear, resulting in an increased
potential for port-to-port leakage of sample. Such leakage can cause erroneous
measurement and materials buildup in the system. When the analyzer detects
sample leakage through the injection valve, it triggers the Injection Valve
Failure alarm and switches the sample diverter valves to flow air through the
injection valve rather than sample.
Note
The Injection Valve Failure alarm must be acknowledged after valve
repair or replacement.
σ
If an injection valve begins leaking due to damage or wear, excess sample
begins flowing to the pyrolyzer. This extra load of sample in the pyrolyzer
exceeds the ability to fully combust the materials in the sample. When these
incompletely combusted materials enter the PUVF optical bench, they absorb
UV light.
The PUVF includes a system to monitor and compensate for decreases in the
UV light output as the bulb ages. However, in the case of injection valve
failure, the PUVF system begins rapidly increasing the UV lamp output in an
effort to compensate for the absorption of UV by incompletely combusted
sample products. The user can enter the rate of change that triggers this
alarm. The programmable range is from 1 to 50 V/30 seconds. If the analyzer
detects the programmed rate of change in UV lamp voltage, it triggers the
Injection Valve Failure alarm to protect the system and reduce the
stabilization time for the PUVF bench on system restart.
When the Injection Valve Failure or Chamber Flow alarm activates, a pair of
sample diverter valves switches to flow air through the injection valve instead
of sample. This prevents excess sample and incomplete combustion products
from further contaminating the system. The diverter valves switch air to the
injection valves under the following conditions:
λ
Injection Failure alarm
λ
Instrument power loss
λ
Instrument air loss
λ
Analysis suspension
Injection Valve
Failure Alarm