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Cooling Tower Test Associates, inc. |
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Since December 1991, Thomas E. Weast has been the designated Certification Administrator of the Cooling Technology Institute (CTI). From 1992 through 1996 Midwest Research Institute (MRI) was the exclusive CTI Certification Licensee performing cooling tower certification tests. Starting in January 1997 the exclusive CTI Certification Licensee to perform certification tests is Cooling Tower Test Associates, inc. (CTTA) which is a new company that was recently formed by Nicholas M. Stich and Thomas E. Weast to provide cooling tower test services. CTTA is pleased to provide its 54 man-years of cooling tower test experience as independent, third-party, cooling tower test engineers to the CTI and its members for both the CTI STD-201 Certification administration and testing.
The following sections summarize the program status and application process.
In July 1991, the CTI Board of Directors revised the CTI Certification Standard STD-201 and adopted an implementation plan for the initial participants in the revised CTI certification program to insure equal access to certification as a group. On July 8, 1992 the initial certifications of 12 lines of towers from four participating manufacturers were announced at the CTI Summer Workshop meeting. In the years following the initial implementation, the number of participating manufacturers and lines of towers has increased to a total of 19 lines of towers from nine participating manufacturers.
Any cooling tower manufacturer which did not participate in the initial implementation schedule is being handled on a first-come--first-served basis as permitted by the schedule of the CTI Certification Administrator and the Certification Testing Agency. A number of inquiries regarding CTI Certification have been received and several applications are currently being processed.
The manufacturer's application should include the items given in Section 3.2 of the CTI Certification Standard STD-201. The time required for data review will be dependent on the quality as well as the quantity of data submitted. Attention should be given to the completeness and organization of the submitted data for each model line presented for certification. Particular attention should be given to the following two items: Section 3.2(b) requires that published ratings be submitted. Section 2.3 in STD-201 defines published ratings and requires that the published ratings "shall be sufficient in scope to permit cooling tower selections and test evaluations over the full range of certified operating conditions claimed by the manufacturer." Section 3.2(c) requires that physical data be submitted. Appendix A in STD-201 (pages 9-11) gives the required information and format for submitting the data of record. Equivalent information in other formats, such as spreadsheets, can be utilized provided the items which are relevant to a given type of tower are all included. To facilitate review if other formats are used, the order of presentation should be in a similar sequence to that used in Appendix A of the STD-201.
When you are preparing the data for initial submission, the subjects of cooling tower installation and optional cooling tower accessories need to be addressed. These topics are discussed in Sections 2.8 through 2.11 and Section 4.2 of the STD-201 and are summarized below. STD-201 should be consulted for the complete text if more detail is desired.
Section 2.8 indicates that the CTI certification only applies when the tower is installed in a free and unobstructed environment.
Section 2.9 indicates that the CTI certification only applies to the exact products submitted for approval or to multiple cell arrangements of the products submitted as long as the physical configuration and airflow through each cell remain unaltered.
Section 2.10 indicates that the CTI certification is not applicable when optional accessories affect the airflow rate through the tower; unless it is certified with the accessories or certified as a separate model.
Section 2.11 indicates that manufacturers participating in the CTI certification program shall not imply that the certification applies to any products not duly certified under the provisions of STD-201.
Section 4.2 indicates that the thermal performance tests conducted by the CTI Certification Administrator shall be conducted with all standard appurtenances such as fan screens, inlet screens, motor and belt guards, and velocity recovery stacks (as applicable) installed.
One of the requirements of the CTI STD-201 Certification Standard is for the Certification Administrator to provide the applicants with the current CTI Schedule of Fees for both the CTI Certification Licensee and the CTI Certification Administrator services.
The expenses incurred by CTTA which are directly associated with the certification of each participants cooling towers will be invoiced by CTTA to the participant with supporting documentation such as time log sheets and travel expense receipts. For new participants, these expenses will consist of the review of submitted data, selection of a model for the qualifying test and the performance of the initial qualifying test. For existing participants, these expenses will consist of the selection of a model for the annual reverification test and the performance of the reverification test.
The data review costs to be incurred by the CTI Certification Administrator will be dependent on the quantity of data submitted for a given model line presented for certification. This could vary from several hours on a simple line with few models to evaluate to several days or more for a line with many models. The completeness and organization of the submitted data may also influence the time required for review. After the selected model for the initial qualifying test has been tested, some additional time will be required to review the test data and verify conformance with the STD-201 requirements. The data review portions of the initial certification process have ranged from about $800 to $2,400 and averaged approximately $1,200 per model line certified. The annual review of the line and selection of a model for the reverification test usually is 25-50% of the initial certification process.
The time required for the initial qualifying or reverification tests will depend on the test equipment used, the number of test personnel required, and the location of the test. On large towers, CTTA will usually provide one test engineer and one supplementary technician to set up and monitor the test equipment, perform water flow and fan power measurements with minimal assistance from plant personnel, and calculate the test results. On smaller towers, such as those usually tested for the CTI certification program, the CTTA technician is usually not required. A typical test will usually require 2-5 days including travel. If the test requirements are out of the ordinary, a pretest site inspection may be warranted in addition to the regular test activities. To aid in accurate billing following the test, the CTTA test engineer prepares a test log which is initialed by the test purchaser's representative during each test. The qualifying test portions of the certification process have ranged from about $1,400 to $4,500 and averaged approximately $2,900 per model line for participants in the USA. International tests are proportionately higher due to the higher costs for air fare, air freight and travel time and are likely to be between $8,000 and $12,000. As more manufacturers participate in the certification program, it may be possible to complete several tests in one trip and prorate the travel expenses between several lines of towers.
For your information, a computerized data acquisition system with 0.01 F resolution will be used to acquire temperature measurements every 5-10 seconds and record the average values every 5 minutes during the test. Sufficient data point locations will be used to insure that the recorded values are as accurate as possible under all test conditions. If applicable, wind speed and direction are also continuously logged with the data acquisition system. After completing the data collection, the CTTA test personnel use the computer to help select stable operating periods for analysis. The program evaluates the test data in 1-hour blocks and determines the statistical stability of each data channel and the collective stability of each test parameter logged by the data acquisition system. The stability is determined by two factors—the rate of change during the time period and the standard deviation or scatter of the readings relative to the rate of change. All test parameters are then automatically averaged for the selected periods.
CTTA presently has test equipment which includes two computerized data acquisition systems used for the certification tests. Two qualified, experienced test engineers will also be available to provide maximum flexibility and minimize scheduling delays.
Early scheduling of tests is highly encouraged, but it is also recommended that the requested dates be realistic and that notification of cancellations and postponements be made as soon as possible so that others can be offered the test date.
In addition to the direct charges to each manufacturer for their data review and testing activities, Section 8.0 of the Certification Standard STD-201 indicates that the general overhead expenses of the CTI certification program incurred by both CTI and CTTA which are not directly attributed to a specific manufacturer's certification review or tests will be prorated between the certification participants. The Certification Administrator is to prepare an estimate of the annual prorated expenses within twenty working days after the beginning of each year. This estimate is subject to review and approval by the Certification Committee which consists of a representative from each manufacturer with CTI certified towers.
For 2002, the general overhead expenses of CTTA and CTI which are not directly attributed to a specific manufacturer's initial certification review and qualifying tests are covered by an administrative program fee of $2,000 per new line of certified towers. The annual administrative program fee for reverification tests is reduced to $1,200 per existing line of certified towers. These rates will most likely remain in effect for the next few years provided the number of participants versus expenses is adequate. These fees will be invoiced by CTI upon completion of the certification process for new lines and at the beginning of each year for continuation of the certification.
If a more detailed cost proposal for a specific inquiry is required, CTTA would be pleased to respond; however, additional time to prepare a reply may be necessary. In order to expedite the implementation of the certification program, it is suggested that the initial response by the participants reference the CTTA price schedule in their purchase orders.
Any questions regarding test scheduling, test preparations, and any other technical details should be directed to Mr. Thomas E. Weast. If I am not available, Mr. Nicholas M. Stich at CTTA may provide assistance.
As a final reminder, CTTA's cooling tower test priorities are:
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Cooling Tower Test Associates, inc. |
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