[摘要]電磁水表?若附著的比液體電導率高的導電物質,丈量易在管壁附著和沉淀物質的流體時。
若附(fu)著的比液體電(dian)(dian)(dian)(dian)導(dao)(dao)率高的導(dao)(dao)電(dian)(dian)(dian)(dian)物質,丈量易在管壁附(fu)著和沉淀物質的流(liu)體時。信號電(dian)(dian)(dian)(dian)勢將被短路而不能工作,若是非導(dao)(dao)電(dian)(dian)(dian)(dian)層則首(shou)先應注意電(dian)(dian)(dian)(dian)極的污染,譬(pi)如選(xuan)用不易附(fu)著尖形或(huo)半球形突出電(dian)(dian)(dian)(dian)極、可更換式電(dian)(dian)(dian)(dian)極、刮刀(dao)式清垢電(dian)(dian)(dian)(dian)極等。
刮刀式電極可在傳感器外定期手動刮出沉垢。國外產品曾有電極上裝超聲波換能器,以清除表面垢層,但現已少見。也有暫時斷開測量電路,電極間斷時間內流過低壓大電流,焚燒清除附著油脂類附著層。易產生附著的場所可提高流速以達到自清掃的目的還可以采取較方便的易清洗的管道連接,可不裝配清洗傳感器。
仍能工作,非(fei)接觸型電極EMF附著非(fei)導電膜(mo)層(ceng)。但(dan)若為高導電層(ceng)則(ze)同樣不(bu)能工作。