The SD83x Power Supply Units are designed to meet all the applicable electrical safety data stated by the EN 50178 harmonized European Standard Publication and the additional safety and function data required by EN 61131-2 and UL 508.

The secondary output circuitry is accepted for SELV or PELV applications. They are switch-mode Power Supply Units that convert the mains voltage to 24 volts d.c. These power supplies can be utilized for non-redundant and redundant applications.

Redundant applications require diode voting units SS823 or SS832. With the type SD83x series Power Supply Units, there is no requirement for the installation of a mains filter. They provide a soft start feature; power-on of an SD83x will not trip fuses or earth-fault circuit breakers.

• Simple DIN-rail mounting
• Class I Equipment, (when connected to Protective Earth, (PE))
• Over-voltage Category III for connection to primary main
  TN network
• Protective separation of secondary circuit from primary circuit
• Accepted for SELV and PELV applications
• The output of the units is protected against over current
  (current limit) and over-voltage (OVP)
• SD834 can be connected in parallel to increase output power
• Both a.c. and d.c. input at SD831 and SD834
• Floating DC-OK relay contact at SD834