Sathish Arul

  STP     Sewage treatment platn (residential & commercial) ETP     Effluent treatment plant (industry) COD     Chemical oxygen demand (soluble & insoluble organic compound) (2hr to 3hr) (mg/l) BOD     Biochemical oxygen demand (organic compound) (3days to 5days) (mg/l) KEY POINTS: Outlet of STP 50mg/l Biproduct of anaerobic digestion is H2S & NH3 To reduce stink smell use ozone 

  RTD                        Resistance temperature detector NTC                      Negative temperature coefficient PTC                        Positive temperature coefficient PT100                    Platinum resistance thermometer 100 (resistance at 0'C) PT1000                Platinum resistance thermometer 1000 (resistance at 0'C) 2 wire RTD          less accuracy than 4 wire RTD 4 wire RTD          more accuracy than 2 wire RTD

  2 way valve & 3 way valve A 2-way valve is any type of valve with two ports: an inlet and an outlet port, typically labelled A and AB respectively. With two ports, the valve passes the water in one direction only. 3-way valves have three ports, labelled A, B, and AB. With three ports, the 3-way valve passes the water in two directions.

  ATS

RELAY 

AVR An automatic voltage regulator (AVR) is  a solid state electronic device for automatically maintaining generator output terminal voltage at a set value . It will try and do this as the generator load or operating temperature changes.