Monitoring of pumps & valves
For the conditioning of fresh water, drinking water and waste water, the fluid is pumped frequently between basins, wells and tanks.
All those plants contain a large amount of pumps and valves, which are controlled mainly automatically by PLCs or control systems. An indication of the proper function of those valves and pumps is the flow of the water in the pipes between the containers. The use of impeller flow meters is very common in these plants.
To detect water flow in case of the pump is running you expect pulses from that impeller wheel. For a closed valve you expect no flow, thus no pulses from the meter. To define that states as good or fault state you can use the pulses to indicate the status of the media und the actors. Thus you proof water flow or not with a simple watchdog timer without any further equipment installed.
The TELE watchdog timer model E1ZMW10, a very compact electronic timer, offers various and selectable impulse detection modes.
Static input signals at whatever level are interpreted as no movement on the impeller. A deenergized relay indicates no media flow and energized relay output active media flow.
Three different watchdog modes are selectable to define a start with energized and deenergized mode as well as a watchdog function with latching function, to switch off a plant and prevent from any automatic start. That offers you the detection of process levels or an real hard alarm function To be useable in many applications the instrument offers a wide range auxiliary supply from 24- 240VADC/DC. International approvals like CE, UL, cUL and EAC are available as standard.