Honeywell FC-PSU-UNI2450U 24 VDC 50 A Safety Power Supply

Description

Key Technical Specifications

Honeywell’s Safety Manager hardware documentation identifies FC-PSU-UNI2450U as a system power supply and specifies V2.1 and V3.0 versions. The documented input is 110-240 VAC, with operating limits of 93-253 VAC.

The documented output is 25 VDC or 28 VDC, with 48 A available at 25 VDC and 43 A at 28 VDC within the stated -5 to +50 °C range.

Product Introduction

Honeywell FC-PSU-UNI2450U is a high-capacity system power supply used in Honeywell Safety Manager installations. It accepts 110-240 VAC and provides 25 VDC or 28 VDC output for Safety Manager system hardware and associated loads.

The unit provides a 100 ms hold-up time at full load, dual overvoltage protection, and low output ripple. Honeywell documentation lists the unit with TUV, CE, and cRUus approvals.

FC-PSU-UNI2450U

FC-PSU-UNI2450U

Installation & Configuration Guide

Stage 1: Pre-Installation Preparation

⚠️ Safety First: This is an AC-input, high-current DC power supply. Isolate the incoming AC supply and downstream DC loads according to the plant’s lockout/tagout procedure before replacement. Do not treat the unit as a low-voltage plug-in module.

Tools Required:

• ESD wrist strap
• Insulated screwdriver set appropriate for the installed terminals
• Calibrated digital multimeter
• Wire labels
• Smartphone or camera
• Existing Safety Manager cabinet drawings

Data Backup:

1. Record the existing FC-PSU-UNI2450U version and nameplate information.
2. Photograph AC input and DC output wiring.
3. Record output-voltage configuration.
4. Document connected load distribution.
5. Confirm the replacement revision against the existing Safety Manager hardware documentation.

Honeywell lists multiple FC-PSU-UNI2450U revisions, so do not order or install solely from the base model number when the site requires a particular revision.

Stage 2: Removing the Old Power Supply

1. Place the Safety Manager system in the approved maintenance condition.
2. Isolate the incoming AC source using the site’s LOTO procedure.
3. Verify absence of hazardous voltage with a properly rated multimeter.
4. Allow the DC bus to discharge and verify the output terminals are at a safe voltage.
5. Label each AC and DC conductor before removal.
6. Disconnect the wiring without pulling on the conductors.
7. Release the mounting hardware and remove the PSU.
8. Inspect the cabinet mounting area and wiring for heat damage or discoloration.

⚠️ Critical: The input is rated for 110-240 VAC, with operating limits extending to 93-253 VAC. Never use the DC output terminals as a reference for identifying the AC input wiring.

Stage 3: Installing the New Module

1. Verify the replacement nameplate reads FC-PSU-UNI2450U.
2. Confirm the required revision before installation.
3. Inspect the enclosure, connectors, terminals, and cable set.
4. Mount the PSU securely in the original cabinet location.
5. Reconnect AC input wiring exactly according to the approved wiring documentation.
6. Reconnect the DC output wiring and verify polarity.
7. Check terminal tightness using the applicable Honeywell/site torque specification.

Configuration Check — Critical:

The FC- provides 25 VDC or 28 VDC output. Confirm the required output setting before energizing the Safety Manager load.

Self-Checklist:

• Correct model and revision
• AC input wiring verified
• DC polarity verified
• Output-voltage setting confirmed
• Grounding verified
• Mounting hardware secured
• All terminals checked

Stage 4: Power-On & Testing

Pre-Power Check:

1. Verify AC input wiring against the cabinet schematic.
2. Verify DC polarity.
3. Check for shorts across the DC output.
4. Confirm protective grounding.
5. Confirm connected load is within the PSU’s rated output capability.

Power-On Steps:

1. Energize the AC input under controlled conditions.
2. Measure the DC output voltage.
3. Confirm the measured voltage corresponds to the configured 25 VDC or 28 VDC setting.
4. Monitor the Safety Manager system for power-supply alarms.
5. Verify downstream controllers and I/O return to their expected operating state.
6. Monitor the PSU under normal load.

Honeywell documentation specifies a 100 ms hold-up time at full load and output-current derating beginning at 50 °C. Do not evaluate a high-temperature installation using the nominal 48 A / 43 A figures without checking the applicable derating curve.

Frequently Asked Questions (FAQ)

Q1: What is Honeywell FC- used for?

FC- is a system power supply for Honeywell Safety Manager hardware. Honeywell documentation identifies it as a 110-240 VAC input, 24 VDC-class system PSU with a 50 A nominal class designation.

Q2: What output does FC- provide?

The technical documentation specifies 25 VDC or 28 VDC output. At 25 VDC, the unit can provide 48 A from -5 to +50 °C; at 28 VDC, it can provide 43 A over that temperature range.

Q3: What versions of FC- exist?

Honeywell documentation identifies V2.1 and V3.0 in its current hardware reference. Earlier documentation also identifies V1.0. Therefore, the revision on the installed nameplate should be checked before treating two units as interchangeable.

Q4: Can FC- directly replace FC-PSU-UNI2450?

Not automatically. Honeywell’s system-hints documentation identifies FC- as the V2.1 replacement for FC-PSU-UNI2450 V1.0 and V2.0, as well as FC- V1.0. Honeywell also warns that older power supplies may require additional components rather than being direct form/fit replacements.

Q5: What is the operating temperature range?

The documented operating range is -5 to +70 °C. Output-current derating applies at elevated ambient temperature, beginning at 50 °C.

Q6: Is FC- suitable for a 230 VAC plant supply?

Yes, 230 VAC falls within its documented 110-240 VAC input range. The specified operating limits are 93-253 VAC, with an input frequency range of 47-63 Hz.

Q7: What should I verify before purchasing a replacement?

Confirm the complete model number, revision, input requirement, output setting, cabinet wiring, and connected load. For Safety Manager installations, also check whether the installed unit is covered by Honeywell’s documented replacement path. This is particularly important when replacing older FC-PSU-UNI2450 revisions.