LMG-1 and LMG-2

The two leak measuring devices are characterized by the following features:

Automatic testing process
Real mass flow measurement
Measuring ranges from 0 … 0.5 l/hour
Digital display of the measurement result in Ncm³/min
Digital display of the test pressure
Continuous display of flow
Different interfaces
Evaluation software (option)

General

The LMG-1 and LMG-2 are intelligent, automatic, microprocessor-controlled flow and leak measuring devices.
They have all the functions that modern leak testers must have. No water or oil bath is required. The measurement takes place quickly. The results are objective and are not influenced by human inattention or other errors. The measurement and test results are displayed numerically. The precise, numerical measurement data enables an accurate assessment of the quality and trend.

Continuous or cyclic function can be selected. The continuous function enables setting and adjustment work on the test specimen. The cyclic function makes operation easier and facilitates automated control.

The devices can also be controlled by a PLC or via PC. Profibus interface is possible. All measurement results can be read out and the adjustable parameters can be programmed via the interfaces.

The LMG-1 can primarily be used in manual workstations.
The LMG-2 has adjustable limit values, indicator lights and outputs for checking the measurement results. It can be used in automatic production but also in manual workstations. An additional keyboard or rotary encoder is available for entering limit values and other parameters.
Two limit values can be set. Conspicuous good / rework / not good messages and relay outputs make evaluation and sorting easier.

Measuring principle and function

The mass flow measurement method is used in the device. Measuring the mass flow has the advantage that the measurement signal is independent of the size of the test object and the test pressure and is directly proportional to the leak rate in standard cm³.
Test sequence: The test specimen is connected to the flowmeter. The test pressure is set. After starting, the test pressure is applied to the test object. The LMG checks whether the test pressure has reached the correct value and is constant. If the pressure has not reached the setpoint due to a leak that is too large or does not calm down due to the unstable condition of the test object, the LMG aborts the test process.
After the test pressure calms down, the device switches over to the measuring sensor. It checks whether the flow has reached a stable value, then it displays the flow value. If the test item is defective and the flow value fluctuates, the device reports after a preset test time that the test item cannot be tested.

If the device has a second test pressure option, the measurement is automatically carried out with the second test pressure. Both measurement results are then displayed.

The standard version of the devices has a measuring range. However, they can also be supplied with several measuring ranges (up to 4).
For devices with several measuring ranges, measurements are initially taken in the highest range. If the measured value is small, the device automatically switches to the next smaller range until the correct measuring range is reached.

Technical description

The device includes the electronic control with display, keyboard and serial interface, sensors for flow and pressure, pneumatic control (solenoid valves, etc.) and pressure preparation devices (pressure regulators, filters).

Display: The devices have a large, 2×16-digit, illuminated LCD text display. Programming the device is very easy thanks to the instructions in the text display. Test pressure, flow measurement values and various other information, such as running functions, times, setpoints, error messages are displayed directly or can be read by switching. Functional information is displayed in plain text.

Keyboard: Function keys with direct effect. The LMG-2 also has a keyboard or an input option via a rotary encoder.

Transmitter: mass flow sensor.

Pressure regulator: The device has a built-in pressure regulator. A second pressure regulator for the second test pressure is an option.

Test pressure control: The test pressure is continuously monitored and displayed digitally.

Setting the parameters: Limit values and other parameters can be set on the LMG-1 via the RS-232 interface, on the LMG-2 via the interface and also via the keyboard/rotary encoder.

Zero point correction: The zero point is checked automatically.

Interfaces: The device has a serial interface (RS-232/V.24) and can also be programmed or controlled through this. The interface makes it possible to output the measurement results to a printer or transfer them to a computer for documentation, report creation, statistical evaluation, graphical representation of measurement curves, histograms and for solving other quality-related tasks.
Special software for the above purposes and other customer-specific tasks can be supplied as an option.
The device can be controlled by PLC. 8 inputs and outputs are available for communication.
Other interfaces, e.g. RS-485, Profibus are possible on request.
Programmable pressure control using an electronically controlled proportional valve is possible (option).

Measuring method: Mass flow measuring method

Measuring ranges: The devices are available with different measuring ranges (please specify when ordering!):

Technical data

Flow (standard measuring range):
0 … 0,5 l/h, 0 … 1 l/h,
0 … 3 l/h,0 … 10 l/h,
0 … 30 l/h,0 … 100 l/h,
0 … 300 l/h,0 … 1000 l/h,
0 … 3.000 l/h,0 … 10.000 l/h
Test pressure: 0 … 3 bar; 0 … 10 bar; 0 … 16 bar.
Resolution: up to 0,0005 Nl/h or 0,01 Nml/min. (Ncm³/min.)
Accuracy: ±2% of full scale value
Operating pressure: up to 21 bar
Control pressure: 5 … 7 bar
Medium: compressed air, dry, filtering better 5µm
Version: 19″ table housing or built-in housing, 3U
Data output: RS-232C inter face and e.g. SPS. Option: RS-485, Profibus.
Power supply: 230 V, 50/60Hz

We are also happy to manufacture special designs and special devices according to customer specifications.