APPENDIX III 



STANDARD TESTING CODE FOR HYDRAULIC TURBINES 



THE following Code has been prepared by a Committee of the Hydraulic 

 Turbine Manufacturers to assist in avoiding misunderstandings in regard 

 to stipulated performances of hydraulic turbines. It is subject to such 

 revision from time to time as will be required by any new developments 

 in turbine testing methods. 



INTRODUCTION 



1. Intended Scope. Hydraulic turbine tests are of two distinct kinds: 

 First, acceptance tests on completed turbines after installation in the power 

 plant; second, experimental tests either on full-sized turbines or models, 

 carried out at manufacturers' laboratories or at a testing flume. Tests of 

 the first kind are for the purpose of determining the fulfillment or non- 

 fulfillment of contracts between the turbine builders and the purchasers. 

 Tests of the second kind are carried out for the purpose of obtaining experi- 

 mental data on which the design of an installation may be based; for sci- 

 entific research work; or for the investigation of special problems. This 

 code is intended to apply only to tests of the first kind. When tests of the 

 second kind are used for determining the performance of a full-sized in- 

 stallation, this application should be made only in accordance with principles 

 which will be stated in section 10, below. 



2. Principal Factors, Meaning and Intent of Terms Used. In com- 

 puting the efficiency of an installation a distinction must be made between 

 the efficiency of the plant and the efficiency of the turbine. The efficiency 

 of the plant may include all losses of energy up to any stated point of 

 delivery, such as the delivery of electric power from the transformers, at 

 the switchboard or at the generator terminals, or may be confined to the 

 total efficiency of the hydraulic installation, for which purpose the power 

 is to be computed as that delivered by the turbine to the generator shaft. 



For the purpose of computing the plant efficiency the total or gross head 

 acting on the plant is to be used, and is to be taken as the difference in 

 elevation between the equivalent still-water surface before the water has 

 passed through the racks, to the equivalent still-water surface in the tail- 

 race after discharge from the draft tube. When the water in the forebay 

 in advance of the racks flows with sufficient velocity to make its velocity 

 head an appreciable quantity, the actual elevation of the water surface shall 

 be increased by the amount of this velocity head. The same process shall 



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