23.8.6 Lipits o lsccur~cy - With the above precautions, and provided the brad to be measured is reason- ably stehdv. an eccuraw :vith *I percent may be expected.

19.9.1 Ttic measurements o: pwwH input tall into two gt-ncra: cfssscs:

a) SomS nlcasurements are t h c s ~ wlijcit ihems~ii,es deterf;:--r!e the z~t i la ; p0WBI 0 7 iofque delivered to the p!lmp srid src, Ih,?rcf-re, i~jsdc snrir?ly :!>ring I,.. test, :tsi!:g some form of transmission dyndmcmeter.

t,) i):,Ici i:,::sji!i~.rn,tntc . I ' : ::;jet: vil: ch i,i:.-:..,t ~:-!3suii:.;ie:.', dilring tt:c g t n p 1, ::, o! ; - . ! , . .c.r inpc! l o the ii;.viii:t eir:~nc-~i:. ;.r,:! i i lc r.. .~.~,in: i~s or ?ubsi:cjt~cn: uet!.rriini!ion o; the r=';l;sn 3.' I' i ouwer inpr:tio rhe power oiiipur of this driving elenienl under identical conditions of the pump test, thus dviving the sfticiency of ?fie driving element.

43.9.2 Cor:e2?ions and ai/oocv&sces ---- Power deliver~d :o ?he piintp slhsft when directly connected st?ai! be ttie povwr 3utpu: of the drivino ;.ic.mrnt. Wiieri riot dirtic;iy ccrriected, CcrrcC1iO:lS shal! be made L r :I?e iossos !;::Iwrre~? ti20 i'riuing e!et-i;!?ni. ~ tnd :he pump. in the ~ f i s f : of flat belt and :?-belt drives, tlie ai;~wanci-s hi bei; lossrs i,:::y LL :.!LC:? i j b 5 a::$ 3 psri:r<n: i ~:pfc!lveiy.

-,>;$>. r ....,.? .:,,?- T*..~ E ; x . 1 .* ,. 'LLie !-.....,. ' ". .

.a .a.30.5 -, C!. ail p:,mp. 0: Liiv,ii r;st-i:-:k:,,?s where ri;f po.-~l. is r,o: in ex!:*>:; c.: 75!<W the acti.i*i pump shall be fcs!ed in The il?;;;i:!6rt:!rc!~'ir /:;j>i,i!;:?~iy.

"ma.- 2 "-'. ,.., "a*". -?c :::>I ;; ;!:& lrdv:G. . .. ,,;-., . .. ,. . ., :: ?Ir;.lI br- r*ermissib!e for the manufacturer to test ociy the number

of sta.2es of ihe driii rnriiicti con:<: ivii:hii; c!?c power iequirzmenfs. If a test is made on a iiniiied >?umber of stages, no i~icreose it, tifliciency s:!a!l be ai!owed lor an iinsreesed number of stages wha:-i predicting the finai periormaiics o i the cor;ipl-!r: bo~,";! zosembly, The head and power shall be increased in direci pro- poitic31 :o thc :-!!inher r' $:age? i:! i l r r iii::rl assernbly, cornparod will? the nunine: of steaes used in rhe isk~raiory :-:st.

13.Ti1.3 Wlien the size of :he bc.wl cx<:cctds 400 mrn (jiltside diameter, a laboratory rest on nodel pump, homologous wirti !he aciuci unir, m;y $12 :is26 2s a basis forthe determination of thl: performance of the $CIU;J~ irnii.

72.1 0.3.2 ii: geiierai, when coiil:.a;? I:i?ar:nieer ar;: ?0 be Sa%:d on model tests. ibd contract shocrld spi:cify triodel performance rsihsr Pita;: i , ; f i rizd actrjti :' i:r ierforn~ince. lii th6 absCrii:r; :>f this ~!ovisioil. a!!owence for tile scale effect, if any, :;i;::li be agreed up!,n ir: w i i t i ~ ~ 3 by the represe!!ial;es Of D Q ! ~ parties prici to linaIization of orde-.

Y 3.10.4 Tesr cf fu//s;zedpuri;;~ a t reriucedspeeds Cn all 7un.p~ or bo:~; asseinbiies (which have zn outside dian:etei exceeding 408 mm) :cviiicii i e q i i e than 75 kW, it shsil be permissible Ic test the actual punip or bowl assernb:y st a speel icwer tiran the specified speed. The reduced speed tests are in general cioseiy representalive ot ies:s 8; fiiil speed. In tests at reduced speed, the rc!aiive power loss in bearing G F . ~ ~ t ~ f f i ~ ~ g box friction ~ n s y !its ~ ~ i c r e ~ s c d , 831 effect which may be appreciabir in small pumps. The hydraulic iriclisn luss~s may be relrriii.,:iy ii:creaseci wtii:n the Reynolds number for '.!he warer passages is redui:ed, 81: altecr wh;cii riiay be zp;;i;:;iable in sriii'i? pomps of !ow specific s!>ael. Therefore, these factors shail be considere~i If? determi!ii;ig ,j ib acceptable ,educed iesi spied.

in order tc maintzir, ?he hydr?.uiic ::milariiy. the siii:i!a:ity relations given in 13.3.2 shall be used for head sitd discharse to celcula:e these qiientities ;I? the specified speed from the acrual nieasured head and dischergo. 'i'he effiiiencv a: t?ie spriziiiod spwd shali h s ca!culated by using the relationship given below:

where 7, =~: eiliciency a i ai iuai lost speed.

7, -7 eificiency at spiscified speed, A, .~. - .specified speed.

N -= actual test speed, and n :: exponen: established by lest data, tho vaiiie of the exponent is 0.17

'$8.10.6 Ail lsrye bow! assembly full speed &st5 or rrodei tests shall be conducted In a manner that the submergence would he that specified by tile manafacli~re,.

$3.11 Hydrostatic Tesfs -- A standard hydrostatic test on the pump or bowl assembly shall be made at one-and-a-halr times the rnaximum discharge pressure.