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The A771 is a CO adapter designed to work with your DMM to measure ambient air CO. Can also be used as a personal CO alarm.

A771 Carbon Monoxide Adapter

The A771 is an advanced state-of-the-art Carbon Monoxide monitor that may be used to measure levels of carbon monoxide (CO) in the parts per million (ppm) range when used with a digital multimeter (DMM).

  • Built-in alarm is preset to 30ppm. Setting can be set by user
  • Use with any DMM with minimum 2 1/2 digit LCD, 2 or 4 Volt DC range and 10M Ohm or greater input impedance
  • Detect CO levels from 0-1999 ppm, with resolution as low as 0.1 ppm and ±5% of reading accuracy
  • Soft pouch included
  • Measure Ambient Air CO With Any DMM!

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The A771 is an advanced state-of-the-art Carbon Monoxide monitor that may be used to measure levels of carbon monoxide (CO) in th part per million (ppm) range when used with a digital multimeter (DMM).

The instrument has both audible and visual alarms when CO has reached the preset level. This unit may be operated as an alarm only personal monitor.

NOTE: The product may be used with any DMM capable of measuring 2-4 volts DC. The signal output is 1 mV DC = 1 ppm CO.

The A771 uses and advanced electrochemical sensor that measures Carbon Monoxide only. A built-in filter reduces most cross-sensitivity to other gases. This product should be used with DMM’s with greater than or equal to 10 megaohm impedance.

Don’t expose yourself to Carbon Monoxide!

Review the list below for the maximum allowable exposure limits and symptoms developed with CO inhalation.

  • 9ppm: The maximum allowable concentration for short term exposure in a living area according to ASHRAE
  • 50ppm: The Federal OSHA standard for continuous exposure in any eight hour period.
  • 200ppm*: Maximum concentration allowable any time according to OSHA. Slight headaches, fatigue, dizziness, nausea after 2-3 hours.
  • 400ppm*: Frontal headaches within 1-2 hours, life threatening after 3 hours. Maximum allowable limit in flue gas according to EPA and AGA.
  • 800ppm*: Headache, dizziness, nausea, and convulsions with 45 minutes. Unconsciousness within 2 hours. Death within 2-3 minutes.
  • 1600ppm*: Headache, dizziness, and nausea within 20 minutes. Death within 1 hour.
  • 3200ppm*: Headache, dizziness, and nausea within 5-10 minutes. Death within 30 minutes.
  • 6400ppm*: Headache, dizziness, and nausea within 1-2 minutes. Death within 10-15 minutes.
  • 12800ppm*: Death within 1-3 minutes.

* With exposure to this concentration and higher the effects can vary depending on size, age, sex, and health.

 Model A771 Specifications
 Carbon Monoxide (CO) Measurement  Range 0 ~ 1999ppm
 Accuracy  ±5ppm or 5% of reading whichever is greater
 Resolution  1ppm
 Output  1mVDC / 1ppm CO into 10M Ohm impedance
 IR Printer Port  No
 Flue Probe  No
 Internal Pump  No
 Combustible Gas Leak Detection  No
 Backlight  N/A
 Alarm  Audible
 Power Supply  9V Alkaline Battery
 Dimensions  6.5” x 2.1” x 1.2” (165 x 55 x 30 mm)
 Weight  7.23oz (205g)
 Warranty  3-year limited warranty 2-year sensor warranty

TPI Model A771 Demonstration Video

Model A771 Applications

  • Ambient CO safety checks

Frequently Asked Questions

Why should I purchase a pump driven CO analyzer rather than a less expensive CO monitor?
A pump driven analyzer is a much more versatile tool. The pump draws a sample into the instrument which allows source pinpointing. A pump driven instrumentwill also respond faster, and can be used for hot air (flue) sampling.

Can a CO analyzer be used for heat exchanger testing?
While a CO analyzer can provide a safety test of the furnace, it cannot provide a discernable test for heat exchanger integrity. The TPI HXG2 and HETKIT are recommended for this test and together are AGA approved.

How often should I calibrate my CO analyzer?
It depends on the use of the instrument. If used for service work, it is recommended that an annual calibration be performed. If any aspect of worker safety is included in the instrument’s job, monthly calibration is recommended.

If I perform my own calibration, do I increase my liability?
As long as traceable calibration gas is used and manufacturer’s calibration procedures are followed, liability will be minimized. Calibration records should be documented and retained.

How many calibrations can I expect out of a 21 liter bottle of calibration gas?
35-50 calibrations

How long will the CO sensor last?
Two to three years.

Product Documentationpdf-icon1

Click below to view or download product documentation PDFs:

A771 Data Sheet

A771 Manual

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