Campbell Scientific ASPTC User Manual

Model ASPTC Aspirated Shield

with Fine Wire Thermocouple

Revision: 6/10

Copyright © 1993-2010

Campbell Scientific, Inc.

Warranty and Assistance

The MODEL ASPTC ASPIRATED SHIELD WITH FINE WIRE
THERMOCOUPLE is warranted by Campbell Scientific, Inc. to be free from

defects in materials and workmanship under normal use and service for twelve
(12) months from date of shipment unless specified otherwise. Batteries have
no warranty. Campbell Scientific, Inc.'s obligation under this warranty is
limited to repairing or replacing (at Campbell Scientific, Inc.'s option)
defective products. The customer shall assume all costs of removing,
reinstalling, and shipping defective products to Campbell Scientific, Inc.
Campbell Scientific, Inc. will return such products by surface carrier prepaid.
This warranty shall not apply to any Campbell Scientific, Inc. products which
have been subjected to modification, misuse, neglect, accidents of nature, or
shipping damage. This warranty is in lieu of all other warranties, expressed or
implied, including warranties of merchantability or fitness for a particular
purpose. Campbell Scientific, Inc. is not liable for special, indirect, incidental,
or consequential damages.

Products may not be returned without prior authorization. The following
contact information is for US and International customers residing in countries
served by Campbell Scientific, Inc. directly. Affiliate companies handle
repairs for customers within their territories. Please visit
www.campbellsci.com to determine which Campbell Scientific company
serves your country.

To obtain a Returned Materials Authorization (RMA), contact Campbell
Scientific, Inc., phone [phone]. After an applications engineer
determines the nature of the problem, an RMA number will be issued. Please
write this number clearly on the outside of the shipping container. Campbell
Scientific's shipping address is:

CAMPBELL SCIENTIFIC, INC.

RMA#_____
815 West 1800 North
Logan, Utah 84321-1784

For all returns, the customer must fill out a “Declaration of Hazardous Material
and Decontamination” form and comply with the requirements specified in it.
The form is available from our website at
completed form must be either emailed to [e-mail]
435-750-9579. Campbell Scientific will not process any returns until we
receive this form. If the form is not received within three days of product
receipt or is incomplete, the product will be returned to the customer at the
customer’s expense. Campbell Scientific reserves the right to refuse service on
products that were exposed to contaminants that may cause health or safety
concerns for our employees.

www.campbellsci.com/repair

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or faxed to

ASPTC Table of Contents

PDF viewers note: These page numbers refer to the printed version of this document. Use
the Adobe Acrobat® bookmarks tab for links to specific sections.

1. General .........................................................................1

1.1 Specifications............................................................................................1

1.2 Power Considerations...............................................................................2

2. Mounting.......................................................................2

3. Programming ...............................................................3

3.1 Absolute Temperature ..............................................................................3

3.1.1 CRBasic ..........................................................................................3

3.1.2 Edlog...............................................................................................4

3.2 Delta Temperature....................................................................................5

4. Maintenance.................................................................8

Figures

2-1. ASPTCs Mounted to Bowen Ratio Arms................................................2

2-2. ASPTC Mounted to the UT018...............................................................2

3-1. Wiring for a Single ASPTC ....................................................................3

3-2. Wiring for a Pair of ASPTCs ..................................................................6

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Model ASPTC Aspirated Shield with Fine Wire Thermocouple

1. General

The model ASPTC is an aspirated shield with a chromel-constantan
thermocouple temperature sensor. One ASPTC can be used to measure
absolute air temperature. Two ASPTCs are used to make delta temperature
measurements. The differential voltage thermocouple instruction (TCDiff in
CRBasic or Instruction 14 in Edlog) is recommended to measure the ASPTC,
because a differential measurement reduces noise.

1.1 Specifications

Weight: 1.9 lbs (0.86 kg)

Shield

Material: UV stabilized polyethylene
Dimensions

Length: 21 inch (53.3 cm )
Height: 5.8 inch (14.7 cm)
Large Outer Diameter: 2.3 inch (5.8 cm)
Small Outer Diameter: 1.8 inch (4.6 cm)

Fan

Air Velocity at
Thermocouple: 5.5 m/s @ 12 Vdc

Life Expectancy: 65,000 hrs @ 30°C
Current Drain: 260 mA @ 12 Vdc
Operating Voltage: 9 to 13 Vdc
Operating Temperature: -10° to 70°C
Reverse Polarity Protected

Thermocouple

Type: Chromel-Constantan
Diameter: 0.003 inch (0.0762 mm)
Typical Output: 60 μV/°C
Accuracy: Refer to the “Thermocouple Measurement”

section in your datalogger manual.

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