KNF LABOPORT N 840 G, chemical-resistant diaphragm vacuum pump, 34 l/min, ATEX marking category 2, 317123

For those in the laboratory who require a higher flow rate than the smaller N 820 G can provide, the KNF LABOPORT N 840 G is a chemical-resistant, oil-free diaphragm vacuum pump with a flow rate of 34 l/min. It covers the higher performance range of the LABOPORT N series and is suitable for applications requiring a higher flow rate, such as larger vacuum chambers or filtration set-ups.

Chemical-resistant materials in the parts in contact with the medium

As with the smaller version, the pump head is made of TFM PTFE, the diaphragm is PTFE-coated, and the valves are made of FFPM. This combination of materials makes the N 840 G suitable for handling and evacuating highly aggressive and corrosive gases and vapours. The maximum operating pressure is 0.1 bar (rel.), and the ultimate vacuum is 6 mbar (abs.), identical to the smaller version.

Stepless speed control and gas ballast valve

The integrated, manual speed control allows the flow rate to be adjusted to suit the specific application. The integrated gas ballast valve supports short process times, even when working with high-boiling-point solvents, by reducing the condensation of vapours in the pump head. A 3-colour status indicator shows the operating status (running, standby, fault) at a glance.

Explosion protection for internal areas in contact with the medium

The N 840 G bears the ATEX marking (Ex) II 2/-G IIB+H2 T3 and is therefore designed for pumping in potentially explosive atmospheres. This marking refers exclusively to the internal, media-contacting area of the pump, not to the installation environment.

More power, more weight

Measuring 177 x 240 x 289 mm (W x H x D) and weighing 11.3 kg, the N 840 G is slightly larger and heavier than the N 820 G, in line with its higher flow rate. It is powered directly from the mains (100 to 240 V AC, 50/60 Hz), requires no battery, and has a power consumption of 100 W. A thermal switch and a mains fuse protect the pump against overload; the degree of protection is IP30. Permissible media and ambient temperatures range from +5 to +40 °C.

Low-maintenance in everyday laboratory use

As the diaphragm vacuum pump operates completely oil-free, there is no need for the regular oil changes required by conventional rotary vane pumps, and there is no risk of oil mist entering the gases being pumped or the laboratory air. This makes the N 840 G a clean vacuum source for applications where contamination-free operation is important, such as when filtering samples or evacuating larger set-ups. A thermal switch and mains fuse provide additional protection against overload during continuous operation, making it suitable for longer process times and higher flow rates in everyday laboratory use.

Connection and common size

The hose connection has an internal diameter (ID) of 9.5 to 8 mm and is made of PVDF. The pump head of size 840 is also listed by the manufacturer under reference number 315994, the same identification number used for the structurally identical drive unit of the SR 840 G and SH 840 G system variants. Anyone who already has experience with one of these system variants of size 840 will therefore also be familiar with the drive unit of the N 840 G.

Typical applications

As a purely oil-free diaphragm vacuum pump, the N 840 G covers a wide range of laboratory applications requiring higher flow rates:

• Conveying and evacuating aggressive or corrosive gases and vapours requiring higher flow rates
• Vacuum filtration of larger set-ups
• Evacuating desiccators and vacuum chambers
• Vacuum supply for drying and vacuum ovens

N, SR or SH: choosing the right configuration

The N 840 G delivers a pure vacuum without the need for additional accessories. For those who also wish to collect condensate or solvent vapours on the suction and discharge sides, the SR 840 G system variant (with two separator flasks) provides a suitable extension. If the recovery of solvents through condensation is the primary objective, the SH 840 G system variant (with separator and high-performance condenser) is the more suitable choice. For those who only require 20 l/min, the more compact N 820 G is available in the same series.

Designed for continuous operation

With a power consumption of 100 W and a stable power supply across the wide range of 100 to 240 V AC, the N 840 G can be operated at different mains voltages without the need for an additional voltage converter. In combination with the stepless speed control and the gas ballast valve, it is therefore also suitable for more demanding, longer-running vacuum applications in the laboratory where a higher flow rate is required.

Technical details

Scope of delivery

• 1x KNF LABOPORT N 840 G diaphragm vacuum pump
• Wrench for hose connection
• Silencer

Individual requirements and procurement service

A suitable spare parts kit is available for the N 840 G. If you have any questions regarding suitable accessories, spare parts or individual requirements relating to your KNF LABOPORT N 840 G, our procurement service will be happy to assist you.