Product Specification Sheet APS642

Rev. 01/2017

SNT333 Switching Power Supply (QwikBUS™ Series)

Architects' And Engineers' Specifications
The Switching Power Supply unit(s) shall be Alpha Communications® / S.T.R.™ QwikBUS™ model SNT333, or approved equal. The SNT333 shall be built into a rugged high impact ABS plastic case, and shall be powered a contractor supplied power cord. Contractor shall furnish the proper C333-2 connecting cable to connect to the  SP333 intelligent controller and to the model T1240 (12VAC) power transformer.

Low voltage wiring shall be used and positive screw terminal and plug-in connectors shall be provided for installation wiring. The SNT333 shall be mountable right to the surface of the wall or in a customer-supplied junction box cabinet (model# CEC152 or equivalent).

Contractor shall observe all local and national electrical and building codes.

SNT333 Switching Power Supply

The Alpha Communications® / S.T.R.™ SNT333 Switching Power Supply is used only with the 2-wire QwikBUS™ series intercom and/or video-intercom systems. The SNT333 provides the regulated 24VDC power needed to control the SP333 QwikBUS™ intelligent controller.

Each SNT333 gets its power from a customer supplied power cord, and will operate on an input of 100 to 240VAC.

Each 2-wire QwikBUS™ system requires a minimum of one SNT333 Switching Power Supply.

  • Easily Installs Right on Finished Wall Surface or in Optional Junction Box (model# CEC152 or equivalent)
  • Operates on Safe Low-Voltage Class II Wiring
  • Positive Screw Terminal and Plug-in Connectors

Height: 3.75" (96mm)
Width: 3.15" (81mm)
Depth: 2.25" (58mm) from mounting surface

Construction: High impact Grey ABS plastic case
Connections: Positive screw terminal and plug-in connectors
Mounting: Surface-mounted (usually installed near the SP333 intelligent controller and other system central equipment).
Temp. Range: 0°C - 50°C
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.