Allen-Bradley 1606-XL240DR 240W Redundant Industrial Power Supply

Module Overview

The 1606-XL240DR is a high-performance, DIN-rail mounted power supply designed for mission-critical automation environments where system uptime is the highest priority. This "DR" (Redundancy) variant is specifically engineered for $N+1$ and $1+1$ redundancy configurations. Unlike standard power supplies that require external diode modules to prevent backfeeding in a failure scenario, the 1606-XL240DR features integrated decoupling diodes. This allows two units to be wired in parallel directly to the same load; if one unit fails, the other instantaneously assumes the full load without a voltage drop, ensuring continuous operation for PLCs, HMIs, and sensitive field instrumentation.

Detailed Engineering Specifications

The 1606-XL240DR combines a robust power stage with flexible input options to suit global industrial standards.

• Product Type: Redundant Switching Power Supply

• Output Power: 240 Watts

• Output Voltage: 24V DC

• Rated Output Current: 10.0 Amperes

• Input Voltage (AC): 100–120V / 200–240V AC (Manual Select Switch)

• Input Voltage (DC): 240–375V DC

• Operational Range: 85–132V / 176–264V AC

• Efficiency: 89% (Typical)

• Ripple/Noise: < 30 $mV_{PP}$ (Peak-to-Peak)

• Hold-up Time: > 25 ms (@ 196V AC)

• Rated Input Current: < 6.0A (@ 115V) / < 2.8A (@ 230V)

• Operating Temperature: 0°C to +70°C (Derating required above 60°C)

• Dimensions (WxHxD): 120 x 124 x 102 mm

• Physical Weight: 0.98 kg (2.16 lbs)

Redundancy and System Reliability

The "Redundant" designation of the 1606-XL240DR refers to its internal Oring Diodes. In a standard parallel setup, if one power supply's internal output capacitor shorts, it could pull down the voltage of the entire 24V bus. The integrated diodes in this module provide a one-way path for current, isolating the failed unit from the healthy one. This architecture is essential for high-availability systems such as wastewater treatment, continuous chemical processing, and safety-instrumented systems.

Installation and Thermal Management

The module is designed for vertical mounting on a standard 35mm DIN rail. To ensure the 89% efficiency rating and prevent premature aging of internal electrolytic capacitors, a minimum cooling clearance of 40mm above and below the unit, and 15mm on the sides, is recommended. The front panel features a "DC-OK" LED and a "DC-OK" relay contact (Green LED), which can be wired to a PLC input to provide an immediate alarm if the power supply output falls below 21.6V DC.

Technical FAQ

Do I need an external 1606-XLSRED module with this unit?

No. The 1606-XL240DR includes internal redundancy diodes. You only need external redundancy modules if you are using standard "XL" series supplies that lack the "DR" or "RED" suffix.

Can I use this power supply for 120V AC and 240V AC without changing settings?

No. This model features a manual select switch located on the side or top of the unit. You must ensure the switch is set to the correct voltage (115V or 230V) before applying power to avoid damaging the internal components.

What is the benefit of the DC input capability?

Supporting 240–375V DC allows this unit to be powered by a common DC bus or a battery backup system, which is common in power utility and substation applications where AC mains may be unreliable.