Differential pressure switches

The DS11 is a combined display and switching device for differential pressure,over and under-pressure for gaseous and fluid media. This series is ideallysuited for various measuring tasks in rough environments. Typical applications are measuring differential pressure between the supply andreturn in heating systems and monitoring filters and pumps. Please contact the manufacturer before using this unit with dirty or aggressivemedia because the unit needs to be adapted in terms of the parts that come intocontact with the media. The device can be used as a functional safety components (SIL) as agreed withthe manufacturer. The device is to be exclusively used for the applications agreed between themanufacturer and the user.

The DS13 is a switching device for differential pressure, over and under-pressure for gaseous and fluid media. This series is ideally suited for various measuring tasks in rough environments. Typical application cases are the monitoring of tanks, filters and compressors. Please contact the manufacturer before using this unit with dirty or aggressive media because the unit needs to be adapted in terms of the parts that come into contact with the media. The device can be used as a functional safety components (SIL) as agreed with the manufacturer. The device is to be exclusively used for the applications agreed between the manufacturer and the user.

The DS21 is a measuring and switch unit for measuring differential pressure under difficult measuring conditions such as: pressure surges, vibrations, frequent switching and high demands on the switching output. Please contact the manufacturer before using this unit with dirty or aggressive media because the unit needs to be adapted in terms of the parts that come into contact with the media. The units in this series are used as flow guards in heat transfer oil systems in compliance with DIN 4754-2 and hot water systems in compliance with information sheet 'Flow 100'. The flow guards comprise a differential pressure transducer, e.g. a measuring orifice, the differential pressure measuring and switch unit and shut-off fittings. The type tests in compliance with DIN 4754-2 and information sheet "Flow 100" only apply in conjunction with a differential pressure transducer, not for a differential pressure measuring and switching device alone. The DS21 can be supplied iwth the following different pressure chambers: aluminium and stainless steel 1.4305. The aluminium pressure chambers can also be supplied with a HART COAT coating.

The DS21 ... H is a measuring and switch unit for measuring differential pressure under difficult measuring conditions such as: pressure surges, vibrations, frequent switching and high demands on the switching output. Please contact the manufacturer before using this unit with dirty or aggressive media because the unit needs to be adapted in terms of the parts that come into contact with the media. The unit is suitable for operation in potentially explosive areas 1 and 2 – Risk from vapours and 21 and 22 – Risk from dust. For every application, the respective installation instructions and the conditions laid out in the section 'Use in explosive areas' must be observed. The unit can be used in safety-related systems. For use in safety-related systems according to 'Functional Safety' (SIL), the correct function of the safety function must be proven.

The DS31 is a differential pressure switch for overpressure, underpressure and differential pressure measurements. The uncomplicated and durable membrane measuring mechanism is suitable for neutral fluid media, e.g. service water, heating water, neutral gases and oils. Due to the pressure or differential pressure to be measured, a one-sided force acts on the membrane. This force moves the membrane system against the pre-tensioned measuring range spring. A switch tappet mounted on the membrane actuates a micro switch. The switch-point can be set with the setting button of the adjustment spindle. One scale and a setting mark attached to the type plate show the respectively set switch-point.

The DS34 is a differential pressure switch for overpressure, underpressure and differential pressure measurements. The uncomplicated and robust membrane measuring mechanism is suitable for all neutral media, such as service water, heating water, neutral gases and oils. Due to the pressure or differential pressure to be measured, a one-sided force acts on the membrane. This force moves the membrane system against the pre-tensioned measuring range spring. A switch tappet mounted on the membrane actuates a micro switch. The switch point can be set with an adjustment spindle. A scale plate and a setting mark attached to the housing indicate the respective set switch point.

The DS35 can be used for limit detection of pressure, underpressure or differential pressure. In differential pressure limit detection applications, the DS35 Series are used primarily for filter condition monitoring in airconditioning and ventilation systems. Applications are overheating protection in air heating systems, frost protection monitoring in heat exchangers, flow monitoring in air ducts/channels, monitoring of blowers and dampers.

DZ23 / DZ24 are fitting for connection and commissioning of differential pressure transmitters of the series DS11, DE16, DE38 und DE39. In a block casing there are three valve components with which the measuring lines can be blocked on the process side and pressure can be compensated on the transmitter side. The DZ24 is additionally equipped with a vent valve for the pressure lines and the valve set. The valves should have metal seals. The valve spindles contain rotating ball bearings that form a wear-free seal to the block casing. The valve spindles are sealed to the outside with O-rings. The hand wheels can be lead-sealed or detached for safety purposes.

The DZ93 is a fitting for connection and commissioning of differ-ential pressure transmitters of the series DE50 in ventilation systems. In a block casing there are three valve components with which the measuring lines can be blocked on the process side and pressure can be compensated on the transmitter side. The valves should have metal seals. In the valve spindles are rotating ball bearings that form a wear-free seal to the block casing. The valve spindles are sealed to the outside with O-rings. The hand wheels can be lead-sealed or detached for safety purposes.

The EA14D_LCD is based on an electronic evaluation circuit that analyses the measuring signals of two external pressure transmitters. The main task is the calculation of the differential pressure that can be displayed and analysed. The signals of the external pressure transmitters can be shown separately for review. The evaluation unit allows two independent switch points to be set. Optionally two additional output signals can be made available. The external pressure transmitters are connected to the differential pressure evaluation unit via flexible plug connection lines. Only the supplied pressure transmitters may be connected. The nominal pressures of the external sensors and the basic measuring range are set ex-works and stated on the type plate. The device can be used as a display and switching unit in combination with two external service sensors (0/4…20 mA and/or 0…10 V). The medium compatibility depends on the technical data of the sensors used.

The EA14D_LED consists of an electronic module and a pair of separated pressure transmitters. It is an intelligent multifunction instrument that measures and displays differential pressure and (optionally) transmits the measured value as a standardized 3-wire electrical signal. Its programmable limit detection functions enables it also to act as an accurate and versatile differential pressure switch. The electronic module converts the analog signals from the pressure sensors and then digitally processes the input values. Its microcontroller provides a high degree of user programmability and tremendous versatility. The electronic module computes the pressure difference, controls the module's digital display and limit signaling on-off outputs, and (optionally) produces a new analog signal output. The readings can be filtered, scaled, inverted, or linearized through a user-defined look-up table. The external pressure transmitters are connected to the electronic module through flexible signal cables terminated by plug-in connectors. Only the pressure transmitters supplied as part of the instrument set can be used. The pressure ratings of the pressure transmitters and the measuring range of the instrument are matched and factory calibrated and marked accordingly on the product identification label.

The FD38 serves to measure the flow of nonaggressive liquid and gaseous media. The manufacturer must be consulted before using the device for aggressive media because media-compatible materials are required for the measuring path. Fields of application include measuring steam, oil measurement, water measurement. The measuring section comprises a measuring orifice with differential pressure removal boreholes and a differential pressure sensor with a sturdy and nonsensitive unit. In case of differential pressure, a force is exerted on the measuring diaphragm which causes a deflection in the direction of the lower pressure. This deflection is transferred to an inductive displacement transducer via a tappet, and is then converted to a square rooted analogue output signal by the microprocessor-controlled electronics. Optionally, there are also two additional switch outputs available.

The device FD39 serves to measure the flow of nonaggressive fluid and gaseous media. It is imperative to consult the manufacturer before using the device for aggressive media because media-compatible materials need to be used for the measuring path. Typical applications are display unit, volume measuring unit, flow security. The measuring path comprises a measuring panel with differential pressure removal boreholes and two independent pressure sensors. The differential pressure created at the measuring panel is measured by the pressure sensors and turned into a root extracted analogue output signal by the microprocessor-controlled electronics. The standard signals 0/4…20 mA and 0…10V are available for the analogue output.