Trafag, 8710, 8720, 8730, 8740, SF6
Switching point adjustment in factory Excellent vibration resistance No false alarms at low temperatures Stainless steel sensor Independent, separated circuits Output: floating change-over contact Trafag, 8710, 8720, 8730, 8740, SF6 Main characteristics
Gas Density Controller for SF6 and other gases
Principle: R eference gas measurement
Measuring range: 0...1 MPa (0...1000 kPa)
Output: floating change-over contact
Switch point: adjustment in factory
Main features
Exact switching following isochore
Excellent vibration resistance
No false alarms at low temperatures
Stainless steel sensor
Independent, galvanically separated circuits
Option: Version fore lowest temperature ranges
Specifications
Main characteristics
Principle: Reference gas measurement
Measuring range: 0...1 MPa (0...1000 kPa)
Output: floating change-over contact
Switch point: adjustment in factory
Accuracy (@ 20°C)
Switching differential typ.
Microswitch 20: < 15 kPa
Microswitch 28/83: < 10 kPa
Accuracy of the reference Miroswitch from the reference isochore (see page 4)
-30...+50°C: < 10 kPa(Filling pressure: < 650 kPa)
-30...+50°C: < 12 kPa（Filling pressure: < 1 MPa)
Microswitch
Rating: see table
Resistance of insulation: > 2 MΩ
Dielectric strength: 2 kV terminal ground
Life time (mechanical)
Microswitch 20: 1 Mio. cycles
Microswitch 28/83: 10 Mio. cycles
Max. difference from the lowest tothe highest
switching point: 130kPa
Electrical connection
Screwed cable gland: see accessories
Terminal screw: 0.2...2.5 mm2
Environmental conditions
Ambient temperatur: -40....+80°C
With Accessories 68/69: -55....+80°C
Media temperature -40....+80°C
With Accessories 68/69: -55....+80°C
Protection: see page 5
Humidity: max. 95% relative
Vibration
Min. Difference from switch point: 5 kPa
20...80 Hz: 4 g
Shock: 50g/ 11ms
Security
Leakage of Reference
chamber: < 0.5 kPa/ year
(5·10-10 kPa·I·s-1)
Service: none,
switch point checking after 5 years
Reference chamber leakage tests: With Helium gas in vacuum process and integral leakage
test in overpressure process
Mechanical data
Material
Sensor:
Housing: 1.4435 (AISI316L)
Filling: G as
Housing: A lSi10Mg, weatherproof painting
Base plate: A lMgSi1, anodized
Screwed cable gland: brass nickel plated
Weight: ~ 600 g
