Transmitter 340 N2
The series 340 N2 BTU transmitter is an economical, compact device for submetering applications using Johnson Controls Metasys® Network Companion™ and Facilitator™ Supervision system.
The 340 N2 calculates thermal energy by measuring liquid flow in a closed pipe system and measuring temperature at the inlet and outlet points. The 340 N2 requires two 10 kΩ thermistors for temperature input. The flow input may be provided by a sensor and many other pulse or sine wave signal flow sensors. The onboard microcontroller and digital circuitry make precise measurements and produce accurate drift free outputs.
The 340 N2 is commissioned using Windows® based software and a A302 programming cable. Calibration information for the flow sensor, units of measurement and output scaling may be downloaded prior to installation or in the field. While the unit is connected to a PC or laptop computer, real-time flow rate, flow total, both temperature readings, energy rate and energy total are available.
The series feature a six-bladed impeller design with a proprietary, non-magnetic sensing mechanism. The impeller shape coupled with the absence of magnetic drag provides accuracy and repeatability throughout the flow range of the sensors. As the liquid flow turns the impeller, a low impedance square wave signal is transmitted with a frequency proportional to the flow rate.