Ludlum Measurements 3100, Руководство пользователя

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1-4
1.2.2 Scope.
This manual covers operations, technical specifications, and user-level maintenance information
required to support the Model 3100. This manual applies to all users of the Model 3100. For more advanced
technical information, see the Model 3100 Technical Repair Standard manual.
1.2.3 General Description. The Model 3100 shown in Figure 1-1 is an instrument with a maintenance-free,
long-life pump that pulls air through the 250 cc ionization chamber to measure the ionization caused by tritium gas
(HT) and to measure air flow internally with a mass air flow sensor. A second internal chamber provides gamma
compensation, allowing operation in higher gamma fields. The auto-ranging digital display provides clear indication
of the current tritium concentration. The measurement of tritium in air normally measures both tritium gas,
designated as HT, and tritiated water vapor, designated HTO. The Model 3100 contains an internal airflow desiccant
compartment that can be switched in-line with the incoming airstream, drying the incoming air. The resulting
measurement then is (ideally) of HT only. The IN-LINE airflow desiccant may also be used when purging the
tritium chamber of adsorbed tritium. The core of the tritium detection is the electrometer chamber, using a state-of-
the-art, low-noise, temperature-compensated electrometer chip. This electrometer can reliably measure the
femtoamperes of current resulting from ionization caused by tritium inside the chamber. The digital display provides
feedback on the tritium concentration, as well as the status of several important conditions, such as temperature,
pressure, power, airflow, chamber bias, and alarm or failure status.
1.3 EQUIPMENT INFORMATION.
1.3.1 Reference Data. Table 1-1 summarizes general information on the Model 3100.
Table 1-1. Reference Data.
DESCRIPTIVE INFORMATION
Manufacturer (Mfr.) Ludlum Measurements Mfr. Part Number 48-4282-1
Mfr. Model Model 3100 Nomenclature Model 3100
SPECIFICATIONS
Chamber Aluminum with powder coat
finish Power
Requirements 115 VAC 50/60 Hz input
with 1.5 A circuit breaker,
or 8 internal rechargeable
NiMH AA cell batteries, or
optional 8 internal non-
rechargeable alkaline
batteries
Chamber Volume approximately 250 cm
3
Primary Battery Life Approximately 16 hours,
with pump running
continuously