Teledyne API Ultrafine Particle Monitor - Model 651

Instrument Description

SETUP screen) is an electronic valve used to turn on/off the vacuum from the external source.

Water System

The water separator removes water from the vapor stream coming from the optics head. This prevents water from condensing and blocking the flow orifices. Water from the separator is pumped out by the water ejector pump.

The instrument flow orifices operate under critical pressure with flow determined by the orifice diameter. Each orifice is protected by a glass fiber filter followed by a separate inline screen to remove contamination which can result from an accidental flooding event.

Fans

Two internal fans cool the instrument; one cools the internal electronics and one dissipates the heat generated during cooling of the condenser.

Circuit Boards

The Model 651 contains the following circuit boards:

Main board

Laser board

Detector board

The main circuit board controls all the primary functions. Feedback circuits on the main electronics board control the internal temperatures (displayed on the Status screen).

Internal Clock

The clock used in the Model 651 is a quartz crystal component embedded in the microprocessor. The accuracy is on the order of about a second per day, but time drift during long periods of data logging is possible. If a higher level of time accuracy is needed, one of the following options should be implemented:

1.Send a serial command to the instrument once per day to reset the M651 clock to synchronize with the data collection tool.

2.If collecting data via the USB stick, reset the clock on the instrument as needed.

07506C DCN6727

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Teledyne 651 operation manual Water System, Fans, Circuit Boards, Internal Clock