Thermo Scientific 3600 PDM, Руководство пользователя

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Introduction
Operating Parameters
1-6 PDM 3600 Instruction Manual Thermo Fisher Scientific
The PDM’s flow rate is 2.2 l/min
±
2.5% when calibrated at set point.
Temperature set points of the air heater and TE heater are set automatically
by selecting the appropriate operating temperature (
Figure 3–12 ) when
programming a shift (Section 3). Programmed shifts can be set up in
advance using the WinPDM software. Currently, one shift-time can be
programmed. Manual samples can be started through a membrane switch
pad located on the top of the unit. All shifts require a 35-minute warm-up
period before data begins collecting. Second samples taken within a
programmed or manual sample do not require a separate warmup.
The PDM will accommodate programmed shift lengths from 1 minute to
24 hours in 1 minute increments. To run shifts longer than 12 hours, be
sure to connect the PDM unit to a charger and perform the sample run in a
fresh-air (non-explosive) environment.
The system flow schematic provides an overview of the TEOM 3600
PDM’s flow connections (
Figure 1–3 ). The air flow enters the system
through a cyclone and is then drawn into a heated flow tube. After the air
stream is heated, it flows into the mass transducer where the particulate
matter is deposited onto the TEOM filter. The air flow is then directed
through the hollow TE (tapered element), through the air temperature and
relative humidity sensor block, past the flow differential pressure sensor,
and finally through the pump. The air stream then exits the system.
The TEOM 3600 PDM maintains a constant volumetric flow rate, and
reports sampled volumes (m3) in volumetric terms (based on the ambient
temperature as measured near the cyclone).
The sampling system determines the ambient temperature and pressure for
flow rate calculations through the use of sensors that continually provide
updated information to the microprocessor system.
Operating
Parameters