4.2.5 POWER SUPPLY ASSY: PS2001-XX

The NV3128 Frame and its Power Supply are UL listed. The Power Supply Module PS2001-01powers the NV3128 from the AC line at a nominal voltage of 115 VAC - 60 Hz or 230 VAC - 50Hz. The power supply is designed to accept input voltages in the range of 88 VAC to 135 VAC, or 210 VAC to 270 VAC and to provide DC outputs of +17V, -17V, +7V, and -7V.

AC Power enters the system through connectors mounted on the rear panel. In addition to providing an AC connection, each connector contains both a 1.6 ampere fuse and a Radio Frequency Interference (RFI) /Electromagnetic Interference (EMI) filter.

This bi-directional filter attenuates noise on the power line and noise generated by the power supply to acceptable maximum limits set by FCC and VDE guidelines. A spare fuse, accessible at the rear of the frame, is included inside the power entry module.

A single PS2001 can safely supply the NV3128. A second may be added for redundancy.

CAUTION: HIGH VOLTAGES EXIST IN THE INPUT AND RECTIFIER CIRCUITRY. ALWAYS USE CAUTION WHEN HANDLING COMPONENTS IN THESE DANGEROUS AREAS.

The AC input voltage is rectified by diodes and filtered by capacitors.

This provides raw DC at a high voltage.

CAUTION: THE SETTING OF J1 SHOULD BE PERFORMED BY QUALIFIED SERVICE PERSONNEL ONLY.

The power input source and jumper location must be consistent.

Jumper J1 is set at the factory for either 115 VAC or 230VAC.

ALWAYS CHECK FOR THE CORRECT SETTING BEFORE

APPLYING POWER TO THE UNIT IN A NEW INSTALLATION.

When the jumper is in the 115 VAC position, the input circuit acts as a voltage doubler. The raw DC output is the sum of the positive and negative half-cycle peak voltages. When the jumper is in the 230 VAC position, the AC input is rectified by the full-bridge diode circuit. Both configurations produce the same nominal 230 VDC raw output voltage.

The power supply module incorporates several protective elements. A common problem with off-the-line switching power supplies is a high peak in-rush current due to low input impedance. A thermistor mitigates this problem by presenting a high startup resistance. As the capacitors start to charge, current flowing in the circuit warms the device dropping the resistance and minimizing its effect on the circuit.

NV3128 RS-422A Machine-Control Data Routing Switch

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Envision Peripherals NV3128 manual Power Supply Assy PS2001-XX