PRODUCT DETAILS
1606-XLERED20 — Dual-Input Redundancy Module, 12–28V DC, 20A
The 1606-XLERED20 is a redundancy module that combines two independent 24V DC power inputs into a single decoupled output, using MOSFET-based decoupling rather than the higher-loss diode method found on older redundancy designs. It sits between two power supplies and the load, allowing either supply to fail or be removed without interrupting the 24V rail feeding the panel's controllers, I/O, and field devices.
Specifications
| Parameter | Value |
|---|---|
| Part Number | 1606-XLERED20 |
| Nominal Voltage | 12–28V DC |
| Input Voltage Range | 8.4–36.4V DC |
| Input Current (per input) | 10 A nominal |
| Output Current | 20 A nominal, 25 A short-circuit max |
| Decoupling Method | MOSFET |
| Voltage Drop | ~60 mV |
| Operating Temperature | −40°C to 70°C |
| Mounting | 35 mm DIN rail |
Two Inputs, One Clean Output
The traditional approach to redundant power — wiring two supplies in parallel through simple diodes — works but costs efficiency: every amp passing through a diode drops roughly 0.7V, which becomes real heat at higher currents. The 1606-XLERED20's MOSFET decoupling drops that loss to around 60 mV, a fraction of the diode equivalent, meaning less wasted power and less heat to manage inside the enclosure for the same redundancy benefit.
Each of the two inputs connects to an independent power supply. As long as at least one input stays within its voltage range, the module's output continues supplying the load without interruption — there's no switchover delay or relay action involved, since the MOSFET decoupling operates continuously rather than switching states reactively.
FAQ
Q: Can this module be used with non-24V supplies?
The module's nominal range covers 12–28V DC inputs, with an extended input tolerance down to 8.4V and up to 36.4V — verify both connected supplies are within this range and reasonably matched in output voltage for proper load sharing.
Q: What happens if both input supplies fail simultaneously?
The module's output drops along with both inputs — it has no internal energy storage of its own. For ride-through during a total power loss, a separate buffer or UPS module upstream of the redundancy module is required.
Q: Does this module require the two input supplies to be identical models?
Not necessarily identical models, but both supplies should be rated for compatible output voltage and current to ensure balanced load sharing and predictable behavior if one fails.
Q: Is a separate fuse needed on each input?
External input protection sized to each supply's rated output current is recommended for fault isolation, consistent with standard DC distribution practice even when the module itself includes internal protection circuitry.



