The SINAMICS S120 liquid-cooled drive units are specifically designed to address the requirements relating to liquid cooling; they are characterized by their high power density and optimized footprint. Liquid cooling dissipates heat much more efficiently than air cooling systems. As a result, liquid-cooled units are much more compact than air-cooled units with the same power rating. Since the heat losses generated by the electronic components are almost completely dissipated by the liquid coolant, only very small cooling fans are required. This means that the devices are quiet in operation. Due to their compact dimensions and almost negligible cooling air requirement, liquid-cooled units are the preferred solution wherever installation space is restricted and/or the ambient operating conditions are rough.

Control cabinets with liquid cooling are easy to implement as sealed units with degrees of protection of IP55.

The product portfolio includes the following liquid-cooled SINAMICS S120 built-in units:

• Power Modules
• Basic Line Modules
• Active Line Modules
• Active Interface Modules
• Motor Modules

The associated system components such as line reactors, motor reactors, dv/dt filters plus VPL and sine-wave filters are air-cooled. Active Interface Modules are available in air-cooled and liquid-cooled versions.

Highlights of the liquid-cooled units

• Up to a 60 % smaller footprint than air-cooled drive converters
• All main components such as power semiconductors, DC link capacitors and balancing resistors are cooled by the cooling circuit
• Only a low flow rate is required
• Uniform pressure drop of 0.7 bar
• Automatic protective functions
• Nickel-plated busbars
• Low noise
• Compatible with all components and functions and tools of the SINAMICS system family
• The power rating can be extended by connecting units in parallel
• No equipment fans

Cabinet units in liquid-cooled version

Liquid-cooled SINAMICS S120 drive units are also available as cabinet units, including cooling system. See section SINAMICS S120 Cabinet Modules > Liquid-cooled units.

Example of a drive line-up with SINAMICS S120 liquid-cooled units