ZSI-94/1
ZSI-94/1 INTRINSICALLY SAFE MAINS POWER SUPPLY
CERTIFICATE:
The power supply is used to power intrinsically safe devices used mainly in underground mines, including devices included in the SBM-96 methane blocking system
DESCRIPTION
The strong construction is clearly visible: shape of the gas meter body shape of rotors construction of main shafts and their bearings material selected for the gas meter body overall dimensions of the gas meter no bending, no twisting, no torque, no vibration The indicator of a standard mechanical gas meter is equipped with a low-frequency output. Additionally, low- and high-frequency outputs or intelligent electronics can be installed. The gas meters are also equipped with multiple Pr points and multiple thermal sockets suitable for easy connection of electronic gas volume conversion devices. The bearings are located outside the timing gears, which allows for the connection between the rotors and the timing gears and makes the construction much stronger than in conventional types of rotary gas meters. Rotor gas meters are designed to provide maximum user comfort. All components, such as the gauge, all glasses and all oil filler caps, are accessible from the front. This also allows the meter to be installed with the back to the wall, saving space, for example in underground installations. All major parts can be replaced on site without special tools. The entire mechanism, including rotors, timing gears and bearings, can be removed from the meter and reinstalled without loss of performance. The front and rear bearings can be replaced in less than 10 minutes. MULTIFUNCTION ONE-CLUTCH CLUTCH In order to eliminate all limitations for all kinds of future improvements, rotary gas meters are equipped with a hybrid magnetic clutch. Using a specially designed magnet inside the gas meter, with just “one click” the reading of the gas meter can be changed from “mechanical” (the magnet is used to drive the mechanical indicator pusher magnet) to “electronic” (the orientation of the magnetic field is used to activate the impulse lines to detect the rotation, direction and position of the rotors). This means that most basic versions of the gas meter are already prepared to be transformed into a sophisticated, fully electronic gas meter with conversion (PTZ) and communication (GSM, ISDN, PSTN, Ethernet etc.) features. MULTIFUNCTION INDICATOR The mechanical indicator has a slot, which allows for maximum flexibility. By changing the slot, the gas meter can be equipped on site with several types of low-frequency sensors (reed or Wiegand sensors) and/or a Tamper detector. The mechanical indicator is 100% hermetic to avoid condensation in the indicator VERIFICATION AND CALIBRATION Rotary gas meters are supplied with a calibration certificate. Initial verification and calibration is performed at the manufacturer's premises on a calibration stand approved by NMI and/or PTB. In the case of rotary gas meters with TWIN rotors, high-pressure calibrations can also be performed on request in approved installations. FEATURES The shape of the gas meter body, the square shape of the rotors and the rigid front support plate make the meter completely insensitive to the stresses of the pipes caused by misalignment. In the case of conventional types of rotary gas meters, the stresses of the pipes often cause the rotors to block or seriously impair their performance. The typical asymmetric rotor tip design allows for a significant increase in screw-on ratio. Since the rotor tip is at least twice as large as the rotor tips conventional, undetected leakage through the gas meter is much smaller, resulting in an increased tightening ratio without increasing the sensitivity of the gas meter to system stresses or dirty gas. The larger tip also means that the tip clearance can be increased, allowing greater tolerances of the measuring chamber in the meter body. PRINCIPLE OF OPERATION OF TWIN ROTORS In rotary gas meters, the pulsations increase with increasing pressure and flow, so that such strong pulsations can be produced that the associated resonance can become destructive to the measuring station. In fact, these pulsations limit the achievable Qmax of the rotary gas meter. Pulsations also affect accuracy because the pressure in the measuring chambers and the displaced volume change. To compensate for sinusoidal pulsation, the flow in the gas meter is divided and measured by two measuring chambers with a phase shift of 45° (180° in terms of a sine wave). As a result, almost 100% of the pulsation is compensated (superimposition of sinusoidal waves shifted by 180°). The residual sine wave is much smaller than the pulsation produced by a rotary gas meter with a single measuring chamber. Eliminating pulsation increases the service life of the gas meter, reduces noise and significantly improves accuracy. Another advantage of the TWIN rotor is that the gas meter becomes very stiff due to the additional double bearing support between the rotors. The combination of the TWIN rotor, square rotors and better timing position makes the gas meter perfectly suited for high pressure applications.
FEATURES/TECHNICAL SPECIFICATION
The strong construction is clearly visible: shape of the gas meter body shape of rotors construction of main shafts and their bearings material selected for the gas meter body overall dimensions of the gas meter no bending, no twisting, no torque, no vibration The indicator of a standard mechanical gas meter is equipped with a low-frequency output. Additionally, low- and high-frequency outputs or intelligent electronics can be installed. The gas meters are also equipped with multiple Pr points and multiple thermal sockets suitable for easy connection of electronic gas volume conversion devices. The bearings are located outside the timing gears, which allows for the connection between the rotors and the timing gears and makes the construction much stronger than in conventional types of rotary gas meters. Rotor gas meters are designed to provide maximum user comfort. All components, such as the gauge, all glasses and all oil filler caps, are accessible from the front. This also allows the meter to be installed with the back to the wall, saving space, for example in underground installations. All major parts can be replaced on site without special tools. The entire mechanism, including rotors, timing gears and bearings, can be removed from the meter and reinstalled without loss of performance. The front and rear bearings can be replaced in less than 10 minutes. MULTIFUNCTION ONE-CLUTCH CLUTCH In order to eliminate all limitations for all kinds of future improvements, rotary gas meters are equipped with a hybrid magnetic clutch. Using a specially designed magnet inside the gas meter, with just “one click” the reading of the gas meter can be changed from “mechanical” (the magnet is used to drive the mechanical indicator pusher magnet) to “electronic” (the orientation of the magnetic field is used to activate the impulse lines to detect the rotation, direction and position of the rotors). This means that most basic versions of the gas meter are already prepared to be transformed into a sophisticated, fully electronic gas meter with conversion (PTZ) and communication (GSM, ISDN, PSTN, Ethernet etc.) features. MULTIFUNCTION INDICATOR The mechanical indicator has a slot, which allows for maximum flexibility. By changing the slot, the gas meter can be equipped on site with several types of low-frequency sensors (reed or Wiegand sensors) and/or a Tamper detector. The mechanical indicator is 100% hermetic to avoid condensation in the indicator VERIFICATION AND CALIBRATION Rotary gas meters are supplied with a calibration certificate. Initial verification and calibration is performed at the manufacturer's premises on a calibration stand approved by NMI and/or PTB. In the case of rotary gas meters with TWIN rotors, high-pressure calibrations can also be performed on request in approved installations. FEATURES The shape of the gas meter body, the square shape of the rotors and the rigid front support plate make the meter completely insensitive to the stresses of the pipes caused by misalignment. In the case of conventional types of rotary gas meters, the stresses of the pipes often cause the rotors to block or seriously impair their performance. The typical asymmetric rotor tip design allows for a significant increase in screw-on ratio. Since the rotor tip is at least twice as large as the rotor tips conventional, undetected leakage through the gas meter is much smaller, resulting in an increased tightening ratio without increasing the sensitivity of the gas meter to system stresses or dirty gas. The larger tip also means that the tip clearance can be increased, allowing greater tolerances of the measuring chamber in the meter body. PRINCIPLE OF OPERATION OF TWIN ROTORS In rotary gas meters, the pulsations increase with increasing pressure and flow, so that such strong pulsations can be produced that the associated resonance can become destructive to the measuring station. In fact, these pulsations limit the achievable Qmax of the rotary gas meter. Pulsations also affect accuracy because the pressure in the measuring chambers and the displaced volume change. To compensate for sinusoidal pulsation, the flow in the gas meter is divided and measured by two measuring chambers with a phase shift of 45° (180° in terms of a sine wave). As a result, almost 100% of the pulsation is compensated (superimposition of sinusoidal waves shifted by 180°). The residual sine wave is much smaller than the pulsation produced by a rotary gas meter with a single measuring chamber. Eliminating pulsation increases the service life of the gas meter, reduces noise and significantly improves accuracy. Another advantage of the TWIN rotor is that the gas meter becomes very stiff due to the additional double bearing support between the rotors. The combination of the TWIN rotor, square rotors and better timing position makes the gas meter perfectly suited for high pressure applications.
DOCUMENTATION
