Working principle of Electromagnetic Heat Meter

 

I. Overview 

Electromagnetic heat meter is a kind of meter to measure the heat released by the heat transport fluid in the heat transfer system. It uses a high precision and high reliability electromagnetic flowmeter as flow measurement, and uses high precision and high stability platinum thermal resistance to do temperature measurement, so that the heat meter has very excellent measurement performance. It can be widely used for heat measurement of central heating, supply heating and air conditioning in residential building communities, office buildings, enterprises and public institutions, etc.

 

Ⅱ. Characteristics

Using 16-bit single chip microcomputer for data calculation, platinum thermal resistance for temperature measurement, electromagnetic flowmeter for flow measurement, high accuracy, stable and reliable use, excellent performance.

The measurement accuracy is not affected by changes in viscosity, density, pressure and conductivity , fluid distribution and other parameters of the heat transfer fluid.

No blocking parts in the measuring tube, no pressure loss, not affected by bad water quality. Wide measuring flow range, flow rate can be arbitrarily set within 1m/s ~ 10m/s.

Large LCD backlight in all Chinese/English display modes, numbers can be clearly read in high light or no light.

With simultaneous display function of accumulative heat, accumulative flow, instantaneous heat, instantaneous flow, water inlet temperature, water outlet temperature, temperature difference and other data, it can query and display the flow rate, power off record and other parameters. Adopting the method of enthalpy heat correction with random temperature change to ensure accurate measurement at different water temperatures.

With the function of unified DC signal and frequency signal output, and this function can be switched between heat and flow parameters.

With batch processing (quantitative output), equivalent pulse output, key control to direct zero clear function.

With RS-485 (RS-232, M-BUS and HART optional), digital communication output is convenient for remote communication.

With password protection , working parameters are not allowed to change without password.

 

Ⅲ. Basic Technical parameters: 

1. Converter parameters

· Power Supply: 220V AC(110VAC ~ 245VAC), 24VDC

· Power consumption: ≤20W (matched power consumption) · Accuracy level: 0.5 or 1 (matched accuracy)

· Protection grade: IP65

·Ambient temperature: Class A

·Temperature resolution: 0.01℃

·Optional temperature measurement range: -30℃ ~ 180℃

·Temperature difference measurement range: 1℃ ~ 90℃

·Maximum flow reading (m³) : 99999999 (ten bits)

·Maximum heat reading (Mwh) : 9999999999 (ten bits)

·Heat unit: kJ, MJ, GJ, kwh, Mwh (optional)

·Analog output: 4 ~ 20mA DC / 600 load resistance (can be switched between heat and flow parameters)

·Pulse output: maximum frequency 5000Hz, pulse width 0.1ms ~ 999.9ms (can be switched between heat and flow parameters)

·Communication: RS-485 (optional: RS-232, M-BUS, HART, etc.)

 

2. Sensor parameters

·Nominal diameter: DN50 ~ DN1400mm

·Nominal pressure: 0.6MPa ~ 4MPa

·Lining materials: high temperature resistant rubber, PTFE, PFA, F46

·Electrode materials: molybdenum stainless steel, Hastelloy B, Hastelloy C, Titanium, Platinum-Iridium alloy, Tantalum

·Structural form: Compact type and Separated type

·Medium temperature: -30℃ ~ 180℃

·Connection mode: flange type

 

3. Temperature sensor technical parameters:

· Sensor type: PT1000

· Installation mode: protective sleeve

· Temperature measurement range: -50℃ ~ 200℃

· Conductor length: 0.6m ~ 15m