1794-PS3

The Allen-Bradley 1794-PS3 is a Power Supply module. This module is part of the Flex I/O product family of distributed I/O modules. This module is mainly used to provide power to a Flex I/O assembly, providing the necessary backplane power to operate the installed modules.

The 1794-PS3 operates at a supply voltage range of 85-264VAC, 47-63Hz while the nominal supply voltage are 120V AC, 50/60 Hz; 1.7 A max. and 230V AC, 50/60 Hz; 1.1 A max. It requires a maximum input current of 1.9 Ampere and able to withstand an inrush current of 40 A typical, 1 AC cycle @ Vin 265V AC, 55 °C. This module also features a power supply hold-up time where Output will stay within specification when input drops out for 1/2 cycle @ 47 Hz, 85V AC with max. load.

The 1794-PS3 provides a nominal output voltage of 24VDC with voltage range of 20.4…27.6V DC, including noise and 5% AC ripple. When installed in horizontal orientation, the output current is 3 Amperes while 2.8 Amperes for other mounting orientations. It has an output power of 72 Watts and output ripple of 1200 mV peak-to-peak. The output of the 1794-PS3 is capable of energizing up to Ten (1) Flex I/O adapters. It has an overcurrent protection of 3.2 Amperes, thermal dissipation of 41.0 BTU/hr and maximum power dissipation of 12 Watts. This power supply has an operating temperature of 0 °C < Ta < +55 °C (+32 °F < Ta < +131 °F), operating shock of 30 g and operating vibration of 5g @ 10…500 Hz.

Note that either 3 Amps or 2.8 Amps is the module's maximum output current, depending on its mounting. The entire module measures 3.7 x 2.7 x 3.4 inches. It uses an open-style enclosure and can be mounted horizontally or vertically using a DIN rail or panel mount. It requires an isolation between the DC output terminals and AC input terminals. The nominal power supply input voltage of this module is 120 to 230 Volts AC, 47 to 63 Hertz, and 1.4 Amps (for 120 Volts AC) or 0.8 Amps (for 230 Volts AC), while its nominal output voltage is 24 Volts DC. It also has a power supply input power of 86 W, a maximum apparent input power of 205 VA, and a maximum transformer load of 250 VA. The maximum input current of this module is 1.9 Amps, minimum load is 50 mA, output power is 72 W, and output ripple is a maximum of +/-5% 1200mV peak-to-peak. The 1794-PS3 module also has a leakage current of a maximum of 0.5 mA RMS at the rated input and output and an overcurrent protection of up to 3.2 Amps. Its power dissipation is 12 W while its thermal dissipation is 41 BTU/hour.