 DDM-EM |
 Operating principle |
 Principe |
These differential pressure flow meters are used for measuring and monitoring gas and liquid flow rates.
The device operates on the differential pressure principle, where the pressure drop is proportional to the square of the volumetric flow rate in the pipeline. The DDM series flow meters consist of an orifice plate with an opening integrated into a flange or threaded fitting.
A detector diaphragm is integrated into the housing of the electronic transmitter. The differential pressure generates a force on the diaphragm. The resulting displacement is transmitted via a piston to an inductive displacement sensor. The electronics evaluate this displacement and convert it into a direct display, switching signal, and output signal.
Measurement reliability depends on stable flow conditions at the measuring point. Straight pipe runs are required: 6 × DN upstream and 4 × DN downstream (DN = nominal pipe diameter).
Several versions in steel, stainless steel, or brass are available:
| DDM-DN | flanges according to DIN EN 1092-1 | |
| DDM-Gi | internal thread according to DIN EN ISO 228 | |
| DDM-Ga | external thread according to DIN EN ISO 228 | |
| DDM-Rp | threaded connection according to DIN EN 10226-1 (ISO 7-1) |
- Each BAMO Kirchner instrument is tested according to applicable CE regulations
- Declaration of conformity available on request
- Latest version available on website
- Production site certified according to DIN EN ISO 9001
| Measuring principle | differential pressure at orifice plate | |
| Pressure differential | Air: 5 to 1000 mbar Water: 100 to 1000 mbar |
|
| Ambient temperature | -10 to +70 °C | |
| Pressure loss | approx. 30–60% of pressure differential | |
| Pressure resistance | 16 bar / 500 mbar (DE90 gas only) | |
| Medium temperature | standard -10 to +70 °C, max. 130 °C (insulated line) Fluid must not freeze HT option: above 130 °C |
|
| Protection | IP65 according to DIN EN 60529 | |
| Accuracy | 5% of full scale |
