Canon 2000 manual Retrotec Gauge and System Calibration, Gauge calibration procedure

Retrotec Gauge and System Calibration

All Retrotec Gauges are calibrated against a Master Reference Calibrator (MRC) that has an accuracy of +/-0.1 Pa or 0.1 %. The concept Retrotec equipment uses is that all of Retrotec’s products are now calibrated against the same reference. When a blower is built, it is calibrated against the MRC for pressure and an ASTM flow chamber for holes. A correction formula is derived for that blower to eliminate all the error. Each gauge used in a system, is calibrated against the MRC also and correction equations are derived that will allow for correction over the entire range. The Retrotec software will have the correction equations for each gauge and blower embedded in the software so all readings are corrected automatically.

For every door fan reading, three calibration corrections occur in the software;

1.the room gauge reading,

2.the flow gauge reading and

3.the blower itself.

Additional corrections:

4.Each flow pressure reading is corrected when the flow is towards the operator to reduce the flow pressure by the room pressure to properly reference the reading.

5.Each flow reading is corrected for temperature.

6.Barometric pressure is not corrected for because to do so would reference the reading to local ambient conditions at the time of the test. Rather, flows are referenced to STP conditions which are: 101,325 KPa, 50% relative humidity and 20C. Humidity can be ignored because its effect is negligible.

Gauge calibration procedure

When the Retrotec CA2001 software is created, a calibration certificate records all correction formula that are then used in the software. Only Retrotec can compile these certificates but it is possible to have local instrument companies perform the calibration. Retrotec will then take their data and create the calibration certificate that can be emailed or mailed in a small text file. This file is imported into the Retrotec software to allow CA2001 to perform all the corrections automatically. The software allows the operator to select the certificate that can be used for any particular test. Normally the operator would use the latest calibration certificate but there are two cases where another certificate may be used:

1.Change back to an old certificate to rework or rerun old data in the form of a new test. Old tests will retain the calibration information along with the test so no change would have to be made unless a new test was run.

2.If different blower and/or gauge combinations were used, a different calibration certificate can be utilized by using the “Change” button on the Home tab. Each one of these combinations requires a separate certificate that can be sent by Retrotec upon request.

2000 Fire Door-Fan Manual updated 2002-05-28 Page 47 of 58