Ul tr aso nic Rangi ng Modu le H C - SR 04 P r odu c t fe a tur es : Ult ra so n ic ra n gin g m od u le HC - S R0 4 p ro vid e s 2 c m - 4 0 0cm n o n-co nt act m ea s u re ment f u nct io n, t he ra n gin g a cc u rac y ca n re a ch t o 3 mm . T he m od u les in clu d es u lt ra so nic t ra n smi tt e rs, re cei ve r a nd co nt ro l c irc u it . Th e b asic p rin cip le o f wo rk : (1 ) Usin g I O t rigg e r f o r a t le a st 1 0 us h igh le ve l s ign a l, (2 ) Th e Mo d u le a u to ma t ica lly s e n ds e igh t 4 0 kHz a n d d e t ect wh e t her t h e re is a p u lse sign a l b a ck. (3 ) I F t h e sign a l b a ck, t h ro ugh h igh le ve l , t im e o f h igh o u t pu t I O d u ra tio n is t h e t ime f ro m se n ding u lt ra so nic t o re t urn in g. Test d is t a nce = (h igh le ve l t im eve lo c it y o f so u nd (3 40M/ S ) / 2 Wi r e c onne c ti ng di r ec t a s fol l o w in g: 5 V S u pp ly Trigg e r P u lse I n p ut E c h o P u lse O u tp u t 0 V G ro und E l e ctr i c P a ra m e te r Work in g Volta ge DC 5 V Work in g Cu rre n t 1 5 mA Work in g Fre qu en cy 4 0 Hz Ma x Ra n ge 4 m Min Ra n ge 2 c m Me a s urin gA n gle 1 5 d e gre e Trigg e r I n p ut S ign a l 1 0 uS TTL p ulse E ch o O u t pu t S ign a l I n p ut T TL le ve r sign a l a n d t h e ra n ge in p ropo rt io n Dim e nsio n 4 5 * 20 * 15 mmTi mi ng d i a gr am T he Timin g d ia gra m is sh o wn b elo w. You o n ly n e ed t o s u pp ly a sh o rt 1 0 uS p u lse t o t h e t rigg er in p ut t o st a rt t h e ra n gin g, a n d t h en t h e m od u le will se n d o ut a n 8 cyc l e b u rst o f u lt ra so und a t 4 0 kHz a n d ra ise it s e ch o. Th e E cho is a d ist a nce o b je ct t ha t is p u lse wid t h a n d t h e ra n ge in p ro port io n . You ca n c a lcu la t e t h e ra n ge t h rou gh t h e t im e in t e rval b e twe e n se nd in g t rigg e r sign a l a n d re ce ivin g e ch o sign a l. Fo rmula : u S / 5 8 = c e nt im et e rs o r u S / 1 4 8 =in ch o r: t h e ra n ge = h igh le ve l t im e * ve lo cit y (3 4 0M/S ) / 2 we s u gge st t o u se o ve r 6 0 ms m ea s u re ment cycle , in o rd er t o p re ve nt t rigg e r sign a l t o t h e e ch o s ign a l. At te n tion: T he m od u le is n o t su gge st ed t o c o n nec t d ire ctl y t o e le ct ric, if c o n ne c t ed e le ct ric , t h e G ND t e rmin a l sh o uld b e co nn e cte d t h e m od u le f irst , o t h erwise , it will a ff ect t he n orm a l wo rk o f t h e m od u le. W hen t e st ed o b je cts, t he ra nge o f a rea is n o t le ss t h an 0 . 5 squ a re m et e rs a n d t he p la ne re qu e st s a s sm oo t h a s p o ss ib le, o t h erwise , it will a ff ect t h e re su lt s o f m ea su rin g.