APWR Power supply

The APWR power supply has four DC outputs delivering the desired voltages for AlphaCom and AlphaCom E exchanges. The power supply is able to supply a STENTOFON AlphaCom exchange equipped with maximum 17 ASLT subscriber cards, which is a fully equipped AlphaCom E20 module. In an AlphaCom E26 exchange, two power supplies are required to supply the complete module; a third can be installed for redundancy.

The power supply is easy to install and connect due to the use of Universal AMP Mate’nLock type output connectors.

WARNING: This 1009703000 power supply is incompatible with the older 1009701000 supply. Do not put power supplies of different types into the same exchange module.

Features

AlphaCom power supply 100 9703 000

• Made for AlphaCom 80+, AlphaCom 138, AlphaCom E20 and AlphaCom E26
• Provides +5 V, +15 V, +24 V, and +32 V
• Universal voltage input range from 90 to 270 VAC
• Each power supply serves 102 standard stations
• Can be connected in parallel for load sharing and redundancy
• Potential-free alarm output to warn of power failure
• The power supply shuts down if one voltage fails for protection against overheating
• Power factor correction for efficient energy use
• Over voltage and short circuit protected
• Plug connector for DC outputs - no screws
• International safety approvals
• LED indicator per output voltage and fault
• Built-in cooling fan

Mounting

Mounting the APWR power supply

• Remove the upper front cover
• Remove the back covers
• Slide the power supply into the rails in the upper compartment from the front side
• Leave the power unit front flush with the exchange cabinet front

Connection

Connection of the power supply in an E26 exchange

• Plug the internal power cable to the power supply
• Route the cable through the holes in the main frame
• Connect the cable to a free power connector on the back plane
• Plug the female end of the mains cable into the power supply and the other to the mains outlet in the cabinet’s upper compartment

Indicators

Indicators on the AlphaCom power supply

• The green indicators are lit when the voltages are correct.
• The red indicator is lit only if there is a fault in the power.
• This indicator is not visible when the front cover is mounted.

Specifications

Minimum load

Introduction

As is normal for many PSU’s, the power supply 1009703000 also has minimum load requirements for its power outputs, as indicated in the specifications for the unit. Under operational circumstances this will never be a problem but during commissioning, when no stations are connected this could be noticeable.

Minimum load requirement for +32V supply

Although the PSU is designed with a minimum load requirement, normally this is not critical; the PSU will start up even with no load at all. The only time when the minimum load requirement may become noticeable is when the exchange is switched off and immediately on again after the exchange has been running for some time. In this case if there are any ASLT cards present in the system with no load to the +32V, e.g. no connected intercom station, the PSU may not start up. The proper way to resolve this situation is to make certain that at least 1 intercom station is connected to each ASLT. Waiting a short time until all capacitors are discharged and the internal temperature has gone down a little may appear to be a sufficient remedy, but this does not fulfil the real minimum load requirement.

The minimum load requirements on the other power outputs are sufficiently handled by the presence of the minimum number of cards required to make the AlphaCom E20 and AlphaCom E26 working exchanges.