1606-XLS120E — 120W DIN Rail Power Supply with Selective Fuse Bridging, 24V DC / 5A

The 1606-XLS120E is a 120W regulated 24V DC DIN rail power supply with selective fuse bridging (SFB) technology — a feature that allows the output to continue supplying current beyond the rated 5A for a brief period when loads demand it, then cleanly disconnects a faulted branch without interrupting power to the rest of the system. It accepts 100–240V AC universal input, mounts on a standard 35 mm DIN rail, and delivers regulated 24V DC at up to 5A continuous. For industrial control panels where supply stability and fault isolation directly affect system reliability, the XLS series sits above basic switchmode supplies in terms of diagnostics and behavior under load faults.

Specifications

Parameter	Value
Part Number	1606-XLS120E
Series	1606-XLS
Output Voltage	24V DC (adjustable 24–28V DC)
Output Current	5 A continuous
Output Power	120 W
Input Voltage	100–240V AC (85–264V AC wide range)
Selective Fuse Bridging (SFB)	Yes — boosts output to blow downstream fuses on fault
Boost Current (SFB)	Up to 2× rated current for up to 4 seconds
Efficiency	≥ 89% @ full load
Holdup Time	≥ 20 ms @ 120V AC full load
NEC Class 2	Yes
Output Voltage Ripple	≤ 100 mV peak-to-peak
Mounting	35 mm DIN rail
Operating Temperature	−25°C to 60°C (derate above 50°C)
Standards	UL 508, CE, ATEX Zone 2, cUL

Panel Design Considerations

Output voltage trim: the output is adjustable 24–28V DC via front potentiometer. Trimming to 25–26V compensates for long cable voltage drop and keeps field devices near their nominal supply voltage at the end of a run.
Mounting orientation: rated for vertical DIN rail mounting. Horizontal mounting reduces maximum output current by ~20% due to reduced convective cooling — derate accordingly.
Downstream fuse sizing: for SFB to work correctly, branch fuses must blow before the SFB boost period expires (4 seconds). Use fast-blow fuses rated below the SFB boost current. Standard slow-blow or thermal fuses may not clear within the boost window.
Derating above 50°C: full 5A available up to 50°C. Above 50°C, maximum current reduces linearly — approximately 2.5% per degree Celsius. At 60°C, maximum current is approximately 4.25A.

FAQ

Q: Can two 1606-XLS120E units be paralleled for 240W / 10A output?

Yes. Set one unit's output 0.2–0.3V higher than the other — the higher-voltage unit picks up load first and the lower-voltage unit balances in as load increases. This provides both redundancy and capacity expansion without a dedicated OR-diode module.

Q: What is NEC Class 2 compliance and when is it relevant?

NEC Class 2 limits available output power to levels that reduce shock and fire risk from wiring faults. In North American installations where local electrical code requires Class 2 power sources for low-voltage wiring, a Class 2-compliant supply simplifies inspection and reduces wiring protection requirements for the 24V distribution.

Q: Does the supply protect against reverse polarity at the output?

The 1606-XLS series output terminals are clearly labeled + and −. The supply does not include internal reverse-polarity protection on the output. Reversed output wiring can damage connected loads and the supply — verify polarity during installation.

Q: How does the 20 ms holdup time benefit a PLC system?

Many PLCs and I/O modules need 10–20 ms of supply voltage to complete an orderly shutdown sequence when AC input power drops. The 20 ms holdup bridges brief AC dropouts — from motor starting inrush, contactor bounce, or utility fluctuations — that would otherwise cause nuisance PLC restarts mid-production.

1606-XLS120E New 1606XLS120E Power Supply 1 Phase 24V 5A 120W PLC Module