Low-voltage power supply The low-voltage power-supply circuit converts the AC power from the wall receptacle into the DC voltage that the product components use. The product has two low-voltage power-supplies for 110 Volt or 220 Volt input. Figure 1-5 Low-voltage power-supply circuit AC input DC controller PSTYP100 ZEROX 24RMT +24VB +24VA SW2 +5VB SW1 +5VC +3.3V PWROFF +3.3VS PWRSWON +12VA ICB Formatter The low-voltage power supply converts the AC power into three DC voltages, which it then subdivides, as described in the following table.
Power switch Table 1-8 Converted DC voltages Main DC voltage Sub-voltage Behavior +24 V +24 VA Constantly supplied 12 Chapter 1 Theory of operation ENWW Fuse Noise filter Fuser control circuit Fuse Noise filter Zerocross circuit +24V +5V Rectifying generation generation circuit circuit circuit Rectifying circuit Protection circuit +12V +3.3V generation generation circuit circuit Protection circuit Remote switch control circuit Low-voltage power supply Noise filter Noi se fil ter Switchin circuit g