Product Overview

The Allen-Bradley 1769-PB2 is a dedicated I/O power supply for the CompactLogix platform.
This power supply mounts directly in a CompactLogix rack or expansion I/O bank.
It provides power to modules on both the left and right sides of its position.
Up to Eight (8) modules can be installed on each side of the 1769-PB2 .
Thus, a maximum of Sixteen (16) modules receive power from one supply.
With its open-type enclosure, the entire assembly requires mounting inside a protective cabinet.
This power supply module includes finger-safe covers and barrier-type terminal blocks for safety.

Technical Specifications

Input Characteristics

The Allen-Bradley 1769-PB2 accepts an input voltage range of 19.2 to 31.2 VDC .
Nominal input voltage is 24 VDC for standard industrial systems.
Maximum inrush current reaches 30 A at 31.2 VDC during power-up.
Power consumption equals 50 VA at 24 VDC under normal load conditions.
Power dissipation measures 7.5 W at 60 °C (140 °F) for thermal management.

Output Characteristics

The 1769-PB2 provides two separate output voltage rails for I/O modules.
Current capacity at 5 VDC equals 2.0 A for logic and backplane power.
Current capacity at 24 VDC equals 0.8 A for field device power.
On each side of the supply, the 24 VDC output delivers 1 A independently.
For 5 VDC, the full 2 A is available across both sides combined.

Power Supply Distance Rating

The Allen-Bradley 1769-PB2 has a power supply distance rating of 8 modules .
This rating applies to each side of the power supply independently.
Consequently, eight modules can connect to the left side of the 1769-PB2 .
Another eight modules can connect to the right side of the same supply.
Do not exceed 8 modules on either side for reliable operation.

Protection and Fusing

An internally installed fuse protects the 1769-PB2 from overcurrent conditions.
Compatible fuse types include Wickmann 19193-6.3A for replacement needs.
Alternatively, use Littelfuse 021706.3MXP as a suitable substitute.
The fuse is not user-replaceable in the field for safety reasons.

Physical Characteristics

Dimensions and Weight

The 1769-PB2 weighs approximately 485 grams (1.07 lb) for handling reference.
Dimensions measure 118 x 70 x 87 mm (4.65 x 2.76 x 3.43 in.) .
With mounting tabs included, height reaches 138 mm (5.43 in.) .
Shipping weight equals 2 pounds with dimensions of 8 x 8 x 5 inches.

Wiring Specifications

Wire size requires 14 AWG (2.5 mm²) solid copper wire for power connections.
Wire insulation must be rated at 90 °C (194 °F) or greater for safety.
Maximum insulation thickness is 1.2 mm (3/64 in.) for terminal compatibility.
For solid conductors, wire size ranges from 22 to 14 AWG .
For stranded conductors, wire size ranges from 22 to 16 AWG instead.
Wire type must be Copper rated at 90 degrees Celsius .

Mounting Options

The Allen-Bradley 1769-PB2 supports both DIN rail and panel mounting methods.
Upper and lower panel mounting tabs are provided on the module housing.
For DIN rail installation, snap the module onto standard 35 mm rail.
For panel mounting, use screws through the mounting tabs provided.
Follow the standard CompactLogix mounting methods for consistency.

Environmental Specifications

Temperature and Humidity

Operating temperature ranges from 32 to 140 °F (0 to 60 °C) .
Storage temperature spans from -40 to 185 °F (-40 to 85 °C) .
Relative humidity tolerance reaches 5 to 95% non-condensing .

Vibration and Shock

Operating vibration rating is 5 G at 10 to 500 Hz for industrial use.
Operating shock tolerance reaches 30 G for panel-mounted configurations.
Non-operating shock tolerance equals 50 G for storage and transport.
Therefore, the 1769-PB2 withstands harsh industrial environments.

Isolation

Continuous isolation voltage rating equals 75 Volts for basic protection.
This isolation separates input power from output circuits.
The Allen-Bradley 1769-PB2 provides safe operation in control panels.

Line Loss Ride-Through

Line loss ride-through ranges from 10 milliseconds minimum to 10 seconds maximum .
This feature maintains output during brief input power interruptions.
Consequently, the 1769-PB2 prevents system resets during momentary voltage sags.

Certifications

The 1769-PB2 carries c-UL-us certification for US and Canadian markets.
CE certification ensures compliance with European safety and EMC directives.
C-Tick (RCM) certification applies for Australian regulatory requirements.
These certifications allow global installation of the Allen-Bradley 1769-PB2 .

Installation Guidelines

First, verify that input power matches the 19.2-31.2 VDC range.
Select the mounting position for the Allen-Bradley 1769-PB2 in your rack.
For maximum capacity, place the supply in the center of your I/O bank.
This allows 8 modules on each side for a total of 16 modules.
Install the 1769-PB2 into the CompactLogix backplane securely.
For DIN rail mounting, snap the module onto 35 mm rail until it locks.
For panel mounting, use screws through the upper and lower mounting tabs.
Connect input power using 14 AWG solid copper wire with 90°C insulation.
Torque terminal screws appropriately for secure power connections.
After wiring, verify that no more than 8 modules exist on either side.
Apply input power and measure output voltages before connecting loads.

Wiring Guidelines

Use dedicated 24 VDC power source for the 1769-PB2 input terminals.
Connect the positive wire to the VDC terminal on the module.
Connect the negative wire to the COM terminal for return path.
For grounding, connect the chassis ground terminal to panel ground.
Keep input power wiring separate from I/O signal cables.
Use cable ties to secure wiring away from sharp edges.
Label both ends of each power wire for future maintenance.

Package Contents

• 1 x Allen-Bradley 1769-PB2 I/O power supply module

• 1 x Finger-safe terminal cover for input connections

• 1 x Module identification label for marking

• 1 x Installation instruction sheet

• 1 x Mounting tab set (pre-installed)

Frequently Asked Questions (FAQ)

1. Can the 1769-PB2 power both CompactLogix and 1769 I/O modules?

Yes, the Allen-Bradley 1769-PB2 powers all 1769 series modules. This includes CompactLogix controllers and discrete I/O modules.

2. What happens if I exceed 8 modules on one side?

Exceeding 8 modules on one side of the 1769-PB2 violates the power supply distance rating. The modules may experience undervoltage or erratic operation.

3. Is the internal fuse replaceable by the user?

No, the Allen-Bradley 1769-PB2 has a non-user-replaceable internal fuse. A blown fuse requires returning the module for factory service.

4. Can I use this power supply with MicroLogix 1500 systems?

Yes, the 1769-PB2 works with MicroLogix 1500 expansion banks. It follows the same power supply distance rating of 8 modules per side.

5. What is the difference between 1769-PB2 and 1769-PA2?

The Allen-Bradley 1769-PB2 accepts 24 VDC input power. The 1769-PA2 accepts 120/240 VAC input instead for different applications.