An industrial power supply converts line voltage into the clean, regulated DC that PLCs, HMIs, sensors, safety relays and fieldbus devices depend on. It is the one component whose failure takes an entire control panel down at once, and rack supplies are tied to a specific platform, so a generic replacement rarely fits. MT.parts keeps 140+ power supplies in stock, from DIN rail units to chassis and DC bus supplies, including models the manufacturer has discontinued.
Where these power supplies are used
- Control panels, feeding 24 V DC to controllers, operator panels, relays and field sensors.
- PLC and I/O racks, as the chassis supply that powers the backplane and the modules in it.
- Servo cabinets, where a DC bus supply feeds several axis drives from a shared bus.
- Fieldbus and network segments, powering DeviceNet trunks and remote I/O drops.
- Critical processes, in redundant AC power supply systems and N+1 arrangements.
- Remote and outdoor cabinets, pump stations and skids where an external supply sits next to the enclosure.
How to choose a replacement power supply
Voltage and wattage alone will not tell you if a unit fits. Check these before ordering:
- Part number first. The exact catalog number on the label is the safest match, especially for chassis supplies. Search it in our catalog.
- Output voltage and number of outputs, 24 V DC in most panels, but also 5 V, 12 V and 48 V, and multi-output units for PLC backplanes.
- Output current in amps, with headroom for inrush from contactor coils, drives and capacitive loads, not just the steady-state load.
- Input voltage and phase, 120/240 V AC single-phase, three-phase, or a DC input version. Many PLC chassis supplies exist in both an AC and a DC input variant.
- Format and platform, DIN rail versus a chassis supply that only fits its own family, since a 1756 chassis supply does not fit a 1769 or a 1746 rack.
- Features and environment, DC-OK or alarm contact, redundancy and buffer modules, power boost behavior, plus derating at the ambient temperature inside the enclosure.
If you are unsure which code replaces yours, send us the nameplate data and our team identifies the correct unit.
New, refurbished and obsolete power supplies
We supply three conditions, and the condition is always stated on the product page. New units are factory-sealed. Refurbished units are inspected, repaired where needed and functionally tested before shipping. Obsolete and hard-to-find supplies are models the manufacturer has discontinued, which is often the only way to keep an older rack or panel powered without rewiring it. Every power supply we ship carries a 12-month warranty.
Power supply brands and series we stock
- Allen-Bradley: 1606-XL, 1606-XLB and 1606-XLE PSUs, ControlLogix 1756 power supplies, SLC 500 (1746) power supplies, Compact I/O (1769) power supplies, FLEX I/O (1794) power supplies, Kinetix 5700 DC bus power supply, DeviceNet PSU
- Siemens: DIN rail and panel-mount power supplies, listed individually by catalog number
- Schneider Electric: DIN rail power supplies and controller supply modules, listed individually by reference
- Omron: switching power supplies for panel and DIN rail mounting, listed individually by part number
- Fanuc: power supply units for CNC and drive cabinets, listed individually by part number
Frequently asked questions
What is the difference between a DIN rail power supply and a PLC chassis power supply?
A DIN rail supply is a general purpose unit: it sits on the rail and feeds 24 V DC to whatever is wired to its terminals. A chassis power supply plugs into or bolts onto the rack of a specific PLC platform and powers the backplane itself, so it is not interchangeable between families. Check which of the two failed before ordering.
Can I replace a discontinued power supply with a newer model?
For DIN rail units, usually yes, as long as output voltage, current and mounting depth match. For chassis supplies it is much tighter, because the backplane connector and the slot are specific to that rack. Replacing with the same discontinued catalog number avoids rebuilding the panel. We stock obsolete supplies for exactly that reason.
Do refurbished power supplies come with a warranty?
Yes. New, refurbished and obsolete power supplies all ship with a 12-month warranty.
How fast can I get a quote?
We reply to quote requests within 24 hours, including part identification when you only have nameplate data.
Do you ship internationally?
Yes. We ship worldwide, including to plants outside the United States.
Can't find your part number?
If the power supply you need is not listed, we source it. Send us the manufacturer, part number and quantity, and our team locates the unit, including discontinued models. Request a quote.
