DHS 4.0 air-main charging systems

Air-main charging systems - compact assistants that make a big difference

DHS 4.0 series electronic air-main charging systems from KAESER not only provide protection for your compressed air treatment components, but also help ensure reliable compressed air quality - even following a complete shutdown of your compressed air supply system. 

With dropping pressure, the flow velocity in the pipework quickly increases and can potentially overwhelm all of the components in the compressed air system. Installation of a KAESER DHS 4.0 air-main charging system guarantees the required minimum pressure and thereby ensures reliable operation, especially when re-starting the system following a shutdown

Thanks to a patented pulse width modulation control concept, each air-main charging system is prepared for every eventuality and, as is KAESER’s way, combines exceptional operational reliability with simple and straightforward operation.

  • Connection diameters from G ½ to G 3 and DN 40 to DN 400
  • for systems with one or more treatment lines
  • Perfect integration thanks to numerous interfaces and configuration options

The benefits

  • Two operating modes:
    Priority: compressed air supply or Priority: compressed air quality. Perfectly adapted to your needs.
  • A brilliantly simple operating concept:
    Easy configuration in 25 languages, immediate recognition of operating state, manual actuation in the event of an emergency: all time-saving features that also increase safety.
  • Connection to SIGMA AIR MANAGER 4.0: 
    DHS 4.0 series air-main charging systems can be connected to the SIGMA AIR MANAGER 4.0 master controller via the SIGMA NETWORK.

Product details


Two operating modes

  • 1 – “Priority compressed air quality”, Pulse-width modulated opening and closing of ball valve and butterfly valve for efficient and proper operation of the compressed air supply.
  • 2 – "Priority compressed air quality" for redundant compressed air networks: in the event of dryer or filter faults, for example, closes off the affected line (set ex works)

Electronic control unit

  • Integrated electronic pressure sensor
  • Pressure regulator 0 – 16 bar
  • High-visibility LED
  • Mechanical indicator
  • Processor unit
  • Pressure monitoring
  • Display (25 languages)
  • Password protection
  • Operating mode selection switch
  • Control unit can be rotated 90°
  • Endpoint monitoring
  • Software update via microSD card
  • Anti-tamper seals for keyboard and operating mode switch to protect against unauthorised access
  • Multi voltage: 100 – 240 V AC, 50/60 Hz or 24 V DC

Pivot drive

  • Spring-loaded pneumatic pivot drive
  • Activates the ball or butterfly valve with internal control pressure
  • Silicone-free grease (standard) for ball and butterfly valve. Silicone-free is an option.


  • Password and operating parameter input via keyboard, e.g. opening pressure, hysteresis, opening/closing times in percent
  • Can be integrated into a master control system
  • Manual operation using key to open in the event of power failure


  • Floating inputs for "external shut-down" e.g. dryer fault
  • Floating outputs for "group alarm", "open", "close" and "pressure monitoring"
  • 4-20 mA air distribution network signal for compressor controllers or master control systems
  • Connection for remote operation
  • Modbus-TCP communications interface with M12 plug-in connection.

Ball valve or butterfly valve

Endpoint mounting capability simplifies remodelling or expansion of the compressed air distribution network. It also facilitates alignment and securing in the pipeline for easy installation.


The DHS 4.0 is equipped as standard with a SIGMA NETWORK interface to make operation even more convenient.

We keep an eye on your compressed air station.
DHS 4.0 fitted to a compressed air station.

In order to ensure proper planning and to benefit from efficient and dependable compressed air system operation, the following should be taken into consideration: in addition to demand pressure and process air requirements, factors such as piping, cooling, ventilation, spatial conditions and environmental aspects should be included in the planning process. A well thought-out system design lays the foundation for effective operation later on. 

Generation, treatment and compressed air storage are essential components when it comes to the supply of compressed air. If the treatment components are overwhelmed by excessively high air flow rates, or if a treatment line is not effectively closed off in the event of a fault, unwanted contamination of the process air will occur. Moreover, unnecessary costs are incurred if the compressors also run at weekends in order to compensate for leakage losses.
With an air-main charging system from KAESER, these issues are a thing of the past.

Reliable compressed air supply with air main charging

Protect your components!

DHS air main charging system applications: Reliable compressed air supply with air main charging
  1. Compressor
  2. Refrigeration dryer with ECO-DRAIN
  3. Filtration with ECO-DRAIN
  4. Air receivers
  1. Electronic DHS 4.0 air-main charging system
  2. AQUAMAT condensate treatment
  3. Compressed air network

Since the network is often depressurised following periods of downtime, there is no flow resistance from the network pressure when the compressors are started. The compressed air treatment components in a compressed air supply system, however, are designed to accommodate the flow rates and speeds that occur in the distribution network when the system is in load operation. Therefore, without back-pressure present, there is the risk that filter and dryer components may become ‘overwhelmed’ by the sudden surge in airflow that occurs when the system re-starts. This can lead to filter element damage and to a raised pressure dew point in the refrigeration dryer. As a result, contaminants such as oil, particulate matter and humidity are introduced into the pipe distribution network and the process air.

Reliable compressed air quality with air-main charging

Trouble-free production!

Reliable compressed air quality with air-main charging
  1. Compressors
  2. Air receivers
  3. Refrigeration dryer with ECO-DRAIN
  4. Filtration with ECO-DRAIN
  1. Electronic DHS 4.0 air-main charging system
  3. AQUAMAT condensate treatment
  4. Compressed air network

Electronic air-main charging systems also prove highly useful during system operation - and are even essential for stations with multiple treatment lines - because they help assure consistently high compressed air quality. If a fault occurs with a dryer or a filter, for example, the air-main charging system is able to shut down and isolate the affected treatment line. This not only assures consistent air quality, but also safeguards the pipe distribution network and the air consumers in your production facility.

Technical specifications

The technical specifications can be found in this brochure: