Split Flow Application - Agilent Technologies G8610A Operation Manual

5.1.3.9 Split Flow
Activating the split flow option properly characterizes the system to an external calibrated
leak, which is influenced by additional vacuum pumping sources. These separate vacuum
pumping sources reduce the amount of helium measured by the leak detector.
The split flow option is very useful for external calibrations were external gain factors
exceed the limit of 50 due to a high helium background (Range Stop E-8). The split flow
factor is also useful for calibrating to a standard leak while in the sniffing mode
(High Pressure Test).
Leak detectors are frequently connected to vacuum systems in parallel with other vacuum
pumps. This can cause errors in readings when testing to a specific value is important. Split
Flow properly compensates for flow differences caused by additional pumps. Settings
available in this mode include:
❑
Setting the value of the installed reference leak.
❑
Step-by-step guidance in setting the split flow value.
❑
Entering set point values for audible and visual alarms.
❑
Enabling an Extended Split Flow routine when testing with low concentrations of
helium and/or to quantify large leak values.
Ground rules and assumptions:
❑
The software limits split flow to no more than 1000 times (3 decades). If the split
flow is turned ON and the leak rate entered is more than 1000 times higher than the
system leak rate, the system will not allow the split flow to turn ON and <> appears.
Agilent Technologies Helium Leak Detector
Figure 5-12 Split Flow Application
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