Frequently Asked Questions:

  1. What cal-gas should I use to calibrate the CO2 analyzer?
  2. How often should I calibrate the CO2 analyzer?
  3. How often change the samle system filter?
  4. How much is the analyzer venting?
  5. What should the sweep valve be set at?
  6. What are the analog output settings?
  7. What is the range of the CO2

1. What cal-gas should I use to calibrate the CO2 analyzer?

The CO2 requires a two point calibration. A gas containing no CO2 such as Nitrogen. The ideal span cal-gas concentration would at the value normaly operating at or alarming at. Alternatively cal-gas to use is 3/4 concentration of the range of the analyzer.

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2. How often should I calibrate the CO2 analyzer?

Calibration checks should be done ever 6 to 12 months. Or as required by site preventive maintenance schedule.

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3. How often should I change the sample system filter?

The Filter should be changed as required. The frequency is dependant on the liquid content and particulates in the gas. A higher volume of a liquids and particulates will require more frequent changes. Filters should be checked when analyzer is calibrated.

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4. How much is the analyzer venting?

The standard CO2 vents 100cc per minute.

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5. What should the sweep valve be set at?

The sweep valve should be just opened slightly until flow can be felt from the tubing. This will reduce lag time and allow liquids to be removed.

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6. What are the Analog Output settings?

4-20mA wiring

The analog output of the CO2 is a 4-20 mA signal calibrated at factory. The connections requires loop power from the PLC. If loop power is not able to be supplied, a powered AO board addition can be purchased.

Symptom Solutions
PLC Indicating 0 mA Wiring to analyzer is incorrect.
Power to loop is not present. If loop power not supplied then Powered AO board option may be required.
PLC Indicating higher or lower signal than analyzer display Scaling of analyzer is different setting on PLC

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7. What is the range of the CO2

The range of the analyzer is set at the time of purchase. This range can be found in the back of the manual or by contacting Envent Engineering. Typical ranges are 0-2000 ppm, 0-20% and 0-100%.

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