1756-PA75R Redundant Power Supply ControlLogix

Allen-Bradley 1756-PA75R Redundant Power Supply for ControlLogix Systems

Product Introduction

The 1756-PA75R belongs to the ControlLogix series of redundant power supplies. Unlike standard power supplies, this module installs outside the chassis. It must work in a pair with another unit of the same catalog number. Automatic chassis load sharing distributes the power demand between the two units. A solid-state relay provides contact output for status monitoring. You can wire this output to an input module or an annunciator.

Mechanical and Environmental Data

Here are the physical dimensions and environmental limits.

Dimensions measure 17.5 centimeters in height, 14.5 centimeters in width, and 13.7 centimeters in depth. In inches, this equals 6.9 by 5.7 by 5.4 inches. Weight is 1.45 kilograms or 3.2 pounds. The enclosure is none, meaning it is an open-style module. Panel mounting is the required installation method. Operating temperature range runs from 32 to 140 degrees Fahrenheit, which equals 0 to 60 degrees Celsius.

Wire size for the annunciator is 22 to 14 AWG stranded copper rated at 167 degrees Fahrenheit. Conductor wire size is 14 AWG.

Redundant System Requirements

Building a redundant power supply pair requires several components. First, you need two units of the 1756-PA75R. Second, you need two redundant power supply cables, such as the 1756-CPR2, 1756-CPR2D, or 1756-CPR2U. Third, you need one redundant power supply chassis adapter. Compatible adapter catalog numbers include the 1756-PSCA2, 1756-PSCA2K, or 1756-PSCA2XT. Optionally, you can add a signaling device like an annunciator for monitoring the operational state.

The 1756-CPR2 cable uses two female ends. These connect to male connectors on the redundant power supply and the chassis adapter module.

Chassis Compatibility

The 1756-PA75R works with the following chassis models: 1756-A4, 1756-A7, 1756-A10, 1756-A13, and 1756-A17. It requires Series B chassis for proper operation.

Installation Guidelines

Follow these steps for a proper redundant power supply setup.

First, mount two 1756-PA75R units outside the chassis on a panel. Then, install a 1756-PSCA2 chassis adapter into the chassis. Next, connect each power supply to the adapter using two 1756-CPR2 cables. Additionally, wire the solid-state relay output to an input module or annunciator for status monitoring. Finally, apply AC power to both units and verify load sharing.

Do not replace the non-replaceable fuse, as it is soldered in place. Moreover, ensure proper ventilation around both power supply units to maintain operating temperature.

Packaging List

The package includes the following items:

One 1756-PA75R redundant power supply module.
One printed quick start guide.

Note: No certificates, warranty documents, or cables are included in the box. Order the 1756-CPR2 cable separately.

Shipping Information

We ship worldwide using FedEx, UPS, or DHL. Orders placed before 2 PM ship same day.

Frequently Asked Questions (FAQ)

1. Can I use a single 1756-PA75R alone without a second unit?
   No. The 1756-PA75R is designed for redundant operation only. You must use it in a pair with another unit of the same catalog number.

2. What cable do I need to connect this power supply to the chassis?
   You need a 1756-CPR2 cable. It has two female ends that connect to the male connectors on the power supply and the chassis adapter module.

3. Does the 1756-PA75R have a replaceable fuse?
   No. The fuse is non-replaceable and soldered in place. If the fuse fails, you must replace the entire power supply unit.

4. What chassis adapter works with the 1756-PA75R?
   Compatible adapters include the 1756-PSCA2, 1756-PSCA2K, and 1756-PSCA2XT.

5. How can I monitor if the power supplies are working properly?
   Use the solid-state relay output. Wire it to an input module or an annunciator. This contact output indicates the supply status.