Hoʻohui ʻo WP401B Pressure Switch i ka cylindrical structural pressure transmitter me 2-relay i loko o ka tilt LED hōʻailona, e hāʻawi ana i ka 4 ~ 20mA hōʻailona hōʻailona o kēia manawa a me ka hana hoʻololi o ke ala ala palena kiʻekiʻe a me lalo. E ʻōpō ana ke kukui kūpono ke hoʻāla ʻia kahi puʻupuʻu. Hiki ke hoʻonohonoho ʻia nā paepae alaala ma o nā kī i kūkulu ʻia ma ka pūnaewele.