MECHANICAL PRESSURE SWITCHES (PRESSOSTATS)

The mechanical pressure switches from Trafag are outstanding for their compact design and high-precision micro-mechanics specially developed and manufactured by Trafag itself. These switches can be installed in any position and need no electric power, making them particularly versatile in application and fully site-independent.

Product programe

The following information provides an initial programme overview. The individual product features are not freely combinable with one another. Further information can be obtained by consulting Trafag product catalogues and data sheets.

Pressure measurement sensors

Piston

For hydraulic applications with frequent switching and abrupt pressure changes.

Metal bellows

For fine control of pressure in liquid, vapor, and gaseous media.

Membrane

For the measurement of liquid, vapor, and gaseous media in applications with high switching frequency, abrupt pressure changes and where a high level of overpressure safety is required.

Housings

Aluminum housings, some epoxy coated, seawater resistant. With or without vision panel for switchpoint indicator.

Methods of pressure measurement

Gauge pressure measurement (also in vacuum)
Single-point or differential pressure measurement

Pressure ranges (values given in bar)Differential pressure measurements

• -1...6
• -1...8
• -1...12
• -1...18

Gauge pressure measurements

• 0.02-0.25
• 0.03-0.4
• 0.03-0.06
• 0.05-1
• 0.6...3.4
• 0.9...1.5
• 0.2...1.6
• 0.2...2.5
• 0...4
• 0...6
• 1...10
• 1...16
• 2...25
• 4...40
• 6...60
• 10...100
• 16...160
• 25...250
• 40...400
• 60...600

Pressure connection

Pressure connection in brass, stainless steel or aluminum with. for instance, the following female threads:

　

• G1/8"
• G1/4"
• M10x1
• M12x1.5

Micro-switch models

　

Various switching capacities

• Verschiedene Schaltdifferenzen Various differential gaps (fixed value or adjustable)
• Gold-plated switching contacts
• Versions for enhanced vibration stability

Switchpoint settings

For standard products, the switchpoint is set by the user. On request, Trafag carries out setting of the switchpoint in line with the specifications of the customer. In such a case, the devices can be supplied complete with calibration certificate upon request.

Electrical connections

All pressure switches are equipped with a clamp or plug-in connection.

Temperature ranges (°C)

Operating temperatures: 0...80/-30...65/-20...70/-25....85/ -40....125
Media temperatures: 0...80/-40...85/-30...100/-25...120/ -15...150/-40...150 　

IP protection rating

IP65

Special approvals

Various certifications such as Ex, Shipbuilding, Railways

Accessories

There is a large choice of accessories such as pressure connector adaptors, pressure peak pulsation dampers, snubbers, etc.

　

» Download data sheet Diagnostic Valve Block H72242
» Download data sheet Accessories H72258

Customized products

Trafag also specially develops and manufactures pressure switches to customer specification.

PRESSURE TRANSMITTERS

At the very heart of Trafag pressure transmitters are pressure sensors based on either thin-film-on-steel or thick-film-on-ceramic technology derived from own in-house development and production. This ensures that the pressure sensors and associated electronics are perfectly attuned to one another, a feature subsequently successfully confirmed through reliable function and long serviceable life.

Trafag is a technology pioneer in the miniaturization of rugged pressure transmitters.

Product programme

The following information provides an initial programme overview. The individual product features are not freely combinable with one another. Further information can be obtained by consulting Trafag`s product catalogs and data sheets.

Sensor technologies

Thin-film-on-steel technology:

Measurement is effected according to the strain gauge principle. Through the force effect of the sample medium, the strain gauge bridge is deformed, changing its electrical characteristics.

Features:

• Very good long-term stability
• Ability to endure elevated medium temperatures
• Completely weld-sealed sensor system made of stainless steel without O-rings
• Very high resistance to overpressure; ideal for rated values up to 2000 bar

Thick-film-on-ceramic technology:

　

Measurement is effected according to the strain gauge principle. Through the force effect of the sample medium, the strain gauge bridge is deformed, changing its electrical characteristics.

Features:

• Resistant to aggressive media
• Ideal for low-pressure ranges
• Sealed with an O-ring

Piezo-resistive systems:

If a force is applied to a silicone crystal, this will change its specific electrical resistivity. In the piezo-resistive process, pressure is indirectly transferred to the silicone crystal via a diaphragm backfilled with silicone oil.

Features:

• Ideal for very low pressure ranges
• Large degree of freedom in arrangement of pressure connections (e.g. front-flush diaphragms)

Housings

The housings of Trafag pressure transmitters are all made of highly resistant stainless steel material.

Pressure measurement methods

• Absolute and gauge
• Single or differential pressure measurement

Pressure ranges (values given in bar)

Differential pressure measurements

• -1...1.5
• -1...5
• 0...1
• 0...2.5
• 0...6
• 0...10
• 0...16

Gauge pressure measurements

• -1...9
• -1...16
• 0...0.1
• 0...0.16
• 0...0.2
• 0...0.4
• 0...0.6
• 0...1
• 0...1.6
• 0...2.5
• 0...4
• 0...6
• 0...10
• 0...16
• 0...25
• 0...40
• 0...60
• 0...100
• 0...250
• 0...400
• 0...600
• 0...1000
• 0...1600
• 0...2000

Pressure connections

The connections are made of materials such as stainless steel or brass.

Examples of threaded connections:

Male threads:

• G1/4"
• G1/2"
• M10x1
• M14x1.5
• M18x1.5
• 7/16"-20UNF
• NPT 1/4
• Female threads:
• NPT 1/4
• G1/8"
• G1/4"
• M10x1
• M12x1.5

Diaphragm versions:

• Internal
• Frontal
• Front-flush

Signal outputs

• 4...20mA
• 0...10VDC
• 0...5VDC
• 1...6VDC
• 0.5...4.5VDC ratiometric
• RS485
• CANopen
• Relay
• Transistors

Switchpoint settings

For standard products, the switchpoint is set by the user. On request, Trafag carries out setting of the switchpoint in line with the specifications of the customer. In such a case, the devices can be supplied complete with calibration certificate upon request.

Electrical connections

• DIN43650A
• DIN43650C
• DIN72585
• M12
• Cable
• Alternative types of connection can also be manufactured.

Temperature ranges (°C):

Operating temperatures: -25....85/-25...125/-40....125
Media temperatures: -25...125/-40...125/-50...135/-25...200

IP protection ratings

• IP65
• IP67
• IP68

Special approvals

Various certifications such as Ex, Shipbuilding, Railways

Pressure peak pulsation dampers

All pressure connections with G1/4" outer thread are prepared for incorporation of a pressure peak pulsation damper.

Accessories

» Download data sheet Diagnostik Valve Block H72242
» Download data sheet Accessories H72258

Customized products

Trafag also specially develops and manufactures pressure switches to customer specification.

THERMOSTATS

Trafag thermostats are available for the following tasks:

• monitoring of room temperature in many different areas of application
• monitoring of room temperature in many different areas of application

The temperature sensors can by choice be supplied fitted directly on the housing or apart.

Product programme

The following information provides a preliminary programme overview. The individual product features are not freely combinable with one another. Further details of profile of each product type can be obtained by consulting our product catalogues and data sheets.

Temperature measurement principle

Single, double, or differential measurement

Temperature ranges (°C)

• -45...15
• -30...40
• -30...30
• -20...40
• -10...80
• -10...35
• -10...25
• 0...30
• 0...35
• 0...45
• 0...60
• 5...15 (Frosti)
• 5...35
• 5...95
• 10...40
• 10...45
• 10...55
• 10...70
• 10...80
• 15...30
• 20...85
• 20...110
• 20...115
• 20...150
• 20...230
• 40...300
• 70...350

Operating temperature (°C):

Ambient temperature at which the device may be operated:

-30...50/-30...70 /-30...85 /-15...70

Sensor types

The capillary tube sensors differ in method of connection:

• Sensor fixed directly at the housing
• Sensor remote from the device (e.g. at very high measurement temperatures, or for remote positioning of sensor and device due to separate disposition of measurement signal loop and measuring point)

» Download data sheet Sensors and Protection Tubes H72114
» Download data sheet Sensors and Protection Tubes H72163

Protection against breakage of capillary tube (option)

Protection against breakage of a capillary tube is an element of safety. Should the capillary tube break or leak, the micro switch switches to off as if the set limit temperature had been reached.

Types of housing

• Polymer: For protected indoor use
• Metal: For industrial in- or outdoor use under harsh conditions

Micro-switch versions

　

• Different switching capacities
• Varied differential gaps (fixed value or adjustable)
• Gold-plated switching contacts for Ex applications
• Versions for added stability against vibrations
• Types with 1 or 2 micro switches (partly with adjustable intervals)

Micro switch reset (option)

The thermostats can be supplied optionally with a reset button. After switching of the micro switch, the switch maintains this condition until it is manually reset. This can be important in the case of safety-relevant applications (e.g. overheating protection). Depending upon device model, the reset button is situated as follows:

• inside the device (housing must first be removed to gain access to the button)
• outside the device (direct access to the button from outside the device)

IP protection ratings

• IP54
• IP65

Switchpoint settings

To set the switchpoint, there are two possibilities:

• via adjusting screw (adjustment by screwdriver)
• via adjusting knob (adjustment by hand)

The switchpoint is adjusted according to a scale. Depending on device model, the adjustment knob is situated as follows:

• inside the device (housing must first be removed to gain access to the knob)
• outside the device (direct access to the knob from outside the device)

For standard products, the switchpoint is set by the user. On request, Trafag carries out setting of the switchpoint in line with the specifications of the customer. In a such case, the devices can be supplied complete with calibration certificate upon request.