The following SIPLUS S7-400 standard CPUs with a graded performance spectrum are available for a wide range of different applications in extreme ambient conditions:

• SIPLUS S7-400 CPU 412-2
  The standard CPU for smaller plants in the mid-performance range.
• SIPLUS S7-400 CPU 414-3
  The standard CPU for medium-sized plants with additional requirements for program scope, processing speed, and communication.
• SIPLUS S7-400 CPU 416-3
  The standard CPU for plants with high requirements in the top-end performance range.
• SIPLUS S7-400 CPU 417-4
  The standard CPU for plants with the most stringent requirements in the top-end performance range.

SIPLUS S7-400 standard CPUs are designed for use in the following environmental conditions:

• Wide range of ambient temperatures from -25 °C to +60/+70 °C
• Where increased resistance to chemical, mechanical and biological loading as well as salt spray is required
• Higher installation altitudes
• In relative humidity up to 100%