2.4 Controller
Overview
The sampler controller is used to control the sample collection and acquire data during sampling. This
consists of a controller, a terminal with LCD screen, a twenty-button keypad and the appropriate
electronic components. The controller is shown below. The lower portion of the figure shows the
connectors on the bottom of the controller. The keypad and display terminal can be removed from the
controller to be closer to the sampler modules. When left in the controller, the cord is contained in the
storage pocket.
Keypad Cord
Storage Pocket
Keypad Cord
Data Jack
LCD
Display
Co
C
Module C Cable
Receptacle
Power
Temperature
Probe
Cables
CompactFlash
Memory Card Slot
Barometric
Pressure Sensor
Collocated Module C
Cable Receptacle
Pump Relays
Cable Receptacles
Keypad
The controller:
•
Provides a status of current sampler operations to the site operator.
•
Provides an interface for recording initial and final measurements of the filters during sample changes
to the site operator.
•
Provides options for selecting sampling protocols.
•
Keeps the current date and time.
•
Switches the filter solenoids and pump relays on and off.
•
Records pressure transducers measurements. A standard configuration has 3 transducers:
Barometric Pressure, One Vacuum per module, and temperature. Measurement is done once a
minute and averages are recorded on the CompactFlash memory card every 15 minutes. The
averages are also recorded whenever there is a power outage or the operator starts the sample
change.
•
Records the solenoid valve number that is open.
•
Downloads all the measurements to the removable CompactFlash memory card.
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