一體式電磁流量計(jì)脈沖輸出方式主要用于計(jì)量方式,輸出一個(gè)脈沖,代表一個(gè)當(dāng)量流量,如1L或1M3等。脈沖輸出當(dāng)量分成:0.001L,0.01L,0.1L,1L,0.001 M3 ,0.01 M3,0.1 M3,1 M3 ,0.001UKG,0.01UKG,0.1UKG,1UKG,0.001USG,0.01USG,0.1USG, 1USG。
用戶在選擇脈沖當(dāng)量時(shí),應(yīng)注意流量計(jì)流量范圍和脈沖當(dāng)量相匹配。對(duì)于體積流量,計(jì)算公式如下:
QL=0.0007854×D2×V (L/S)
或 QM=0.0007854×D2×V×10-3(M3/S)
這里; D — 管徑(mm)
V — 流速(m/s)
如果,流量過大而脈沖當(dāng)量選的過小,將會(huì)造成脈沖輸出超上限,所以,脈沖輸出頻率應(yīng)限制在2000P/S以下。當(dāng)然,流量小而脈沖當(dāng)量選的過大又會(huì)造成儀表很長時(shí)間才能輸出一個(gè)脈沖。
另外,必須說明一點(diǎn),脈沖輸出不同于頻率輸出,脈沖輸出是累積夠一個(gè)脈沖當(dāng)量就能輸出一個(gè)脈沖,因此,脈沖輸出不是很均勻的。一般測(cè)量脈沖輸出應(yīng)選用計(jì)數(shù)器儀表,而不應(yīng)選用頻率計(jì)儀表。