Thermatel® Td1 And Td2 Flow/level/interface Switches
Thermatel TD1/TD2 switches can easily be adjusted to detect flow (gases and liquids), level or liquid-liquid interface. TD1 is a line powered 24 V DC unit with integral electronics and a built-in DPDT relay. TD2 is either V DC or V AC line powered, has integral or remote electronics and offers additional LED indication, time delay and mA output for diagnostics and trending.
With continuous diagnostics, automatic temperature compensation, narrow hysteresis and fast response time, TD1/TD2 bring you the latest in thermal dispersion technology.
Operating Principle
The THERMATEL sensor consists of two RTD elements. One is the reference and the second is heated to a temperature above the process temperature. The electronics detect the temperature difference between the two elements. The temperature difference is greatest in air, then decreases when cooling occurs due to a change in media. An increase in the flow rate further decreases the temperature difference.
The set point is adjusted for the switch to alarm at the desired temperature difference. Once the set point is reached, the relay will change state.
Applications
- Pump protection
- Cooling water/Cooling air
- Chemical feed pumps
- Relief valve monitoring
- Lubrication systems
- Exhaust flow monitoring
- Seal leakage
- Safety showers/Eyewash stations
- Leak detection
- Vacuum pumps seal fluid
- Paint flow
- Sampling systems
- Analyzer flow
Features
- Temperature compensated to provide repeatable alarm under varying process temperatures
- Continuous diagnostics detect sensor fault
- Non-linear mA output signal can be used for trending, diagnostics and repeatable flow/level indication
- Detects minimum flow or presence / absence of flow
- Easy / fast calibration
- Excellent low flow sensitivity
Options
- Hot tap retractable probe
- Hygienic design
- NACE construction
- Window to view alarm status
- Integral or remote electronics
- Flow body for very low flow detection
