Ex-proof combination-measuring devices with automatic heavy gas display

DVGW regulation G465-4, issued in March 2001, demands amongst other things, that instruments used for localization purposes shall dispose, besides the methane display, of an automatic heavy gas display (carbon dioxide). New devices, using two thermal conductivity sensors within the measuring range 0.0 ... 100 vol. %, meet this demand as follows:

The advantages:

• Pinpointing the the edge of stationary gas zone of 0.1 vol. % fuel gas
(DVGW G 465-4)
• Localization of small leakages, even though methane already mostly transformed into carbon dioxide
• High resolution in lower measuring range
• Both methane and carbon dioxide concentrations are always measured and displayed
• Linear characteristic, as the thermal conductivity sensors´operating temperature lies below the explosive limit of all gas components. Therefore no combustion at the sensors will take place
• Demands of EN 50058 and G 465-4 are met

EX-TEC® SR 6

• Leak detection
  ppm range
• Localization
  Vol. % range
• Gas warning
  % LEL range
• Domestic services
  ppm range
• Gasing/Inertisation

Vol. % range

VARIOTEC® 9-EX

• Leak detection
  ppm range
• Localization
  Vol. % range
• Domestic services
  ppm range
• Gasing/inertisation Vol. % rangeProbe overview
  Various probes are available for diverse applications:

Probes for network survey
Carpet probe
for the survey of paved surfaces. The gas sample is taken in without disturbing waste fumes via a neoprene mat covering the surface with a pressed-in dome

Bell probe, telescopic bell probe
for the survey of unpaved and overgrown surfaces, provides more mobility, e. g. between parked cars or in front gardens

Probes for localization
Localization probe
for measuring concentrations in probe holes, with hard rubber cone to seal the probe hole, 2 different probe tips (length 245 mm or 345 mm)

Probes for confined spaces
Floating probe
for measuring concentrations in pits, floating body with suction vent and hose connection

Divisible hand probe
for leak detection at free-lying conduits or points difficult to reach, measuring concentrations in containers, total length 900 mm

Probes for domestic services
Flexible hand probes
for leak detection at installation conduits, handle with flexible swan neck and probe hose, total length 360 mm or 660 mm

Testing technique
According to DVGW Regulation G 465-4, instruments used for systematical leak detection have to be checked daily in respect of sensibility and adjusted if necessary before such work is carried out.

This control entails the gasing from a pressure gas can (or bottle, resp.) and also controlling the pump capacity with a flowmeter.

Several test sets (for mobile application) are available for this purpose. Which test set suits each instrument can be seen from the product information "Test sets SPE".

The test set SPE 2 is especially designed for the stationary use at the workshop. This test set can be connected simultaneously with multiple test gas bottles.

Charging technique
The instruments can be recharged with the charging station HS. This charging station can be kept at the workshop or be mounted in the service vehicle.

The following connection types are available:
• AC/DC adapter for 100 ... 240 V ~
• Car charging cable for 12 V =
• Car charging cable for 24 V =

System case
The system case accommodates the measuring instrument, the charging technique as well as the probes.
The big advantage: While inside the closed case, the instrument can be charged from the outside.

Specifications

Passive EX-protection
The instrument variants EX-TEC® SR 6 and VARIOTEC® 9-EX are ex-proof in accordance with European standard (CENELEC):

Active EX-protection
The EX-TEC® SR 6 was additionally tested in mode gas warning on function safety: