What is a PS series 24Vac DIN mount power supply?

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A PS series 24Vac power supply is basically a step down transformer mounted to a DIN bracket to simplify installation. The PS 120 solid state relay, PS-240 and PS-480, along with the “-3” suffix three-phase versions, include terminal blocks for both the input and output connections. The PS-120-208-240, PS-120-208-240-277, and the PS-480-40VA 24Vac power supplies have “flying lead wires” for both the input and output (primary and secondary). The wire color for the output voltage determines the voltage level provided. Several different models of the PS series 24Vac DIN mount stepdown transformers are available to cover a wide variety of line voltages; 110Vac / 120Vac to 24Vac stepdown transformer, DIN mount 208Vac to 24Vac step down transformer, DIN mount 240Vac to 24Vac step down transformer, DIN mount 277Vac to 24Vac step down transformer, DIN mount 480Vac to 24Vac step down transformer, DIN mount

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What is meant by the VA (volt-ampere) rating on a PS series power supply?

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A VA (volt-ampere) rating is used to determine power rating of the power supply and is basically equivalent to watts. The PS-120, PS-240 and PS-480, along with the “-3” suffix three-phase versions, have a 24Vac output and rated to 1.5VA. Therefore, the maximum current they can provide is 1.5VA ÷ 24Vac = 62.5mA. The PS-120-208-240, PS-120-208-240-277, and the PS-480-40VA 24Vac power supplies are rated to 40VA. Therefore, they are capable of providing 40VA ÷ 24Vac = 1.67 amps of output current.

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What do the various wire colors used for on the 40VA 24Vac PS series power supplies?

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The output (secondary) voltage of a 40VA PS series power supply is always 24Vac, with the wires being either blue and yellow, or yellow/white and yellow, depending upon the power supply you’re using. The input (primary) wire color is selected according to the AC mains supply voltage. For example, the blue and yellow wires on a PS-120-208-240 provide the 24Vac output. If the AC mains voltage is 120Vac, then the black and white wires would be connected to the AC mains. If the AC mains voltage is 208Vac, then the black and red wires would be connected to the AC mains. Finally, for a 240Vac AC mains, the black and orange wires would be connected to the AC mains. The black wire is the common connection on all versions.

Additional information is provided in the product datasheets.

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What are the dimensions and weight of a PS series 24Vac power supply?

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The dimensions and weight vary by part number. Each product datasheet provides the dimensions for each part number. The approximate weight for each product is provided below; PS-120; appx. 0.23 lbs PS-240; appx. 0.24 lbs PS-480; appx. 0.29 lbs PS-120-208-240; appx 1.5 lbs PS-120-208-240-277; appx. 2 lbs PS-480-40VA; appx. 1.5 lbs

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Where are the PS series 24Vac power supplies commonly used?

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The PS-40VA series power supplies are essentially used wherever a 24Vac source is needed with a total VA rating of less than 40VA (1.67 amps). There are countless applications, including security systems, HVAC systems, mass transit panels (busses, trains, etc..), access control, video monitoring, and more.

The PS-120, PS-240 and PS-480, along with the “-3” suffix three-phase versions, are also commonly used for stand-alone applications. However, they’re most commonly used with our LPC and TP series phase angle and burst fire solid state relays and power controllers. These products can proportionally control power to AC loads up-to 100 amps and require an auxiliary 24Vac power supply. The PS 1.5VA power supplies can be mounted to the LPC or TP series power controller assembly as a standard option. Please contact us if you’d like additional information - 800.879.7918 / support@hbcontrols.com

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