Description
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | 80026-173-23 / MOX12-P3509 |
| Manufacturer | ABSOLUTE / ABSOPULSE |
| Module Type | DC-DC Power Supply / Switching Module |
| Input Voltage | 42-258VDC (Max 8A) |
| Output 1 | COM1: ±5VDC @ 10A |
| Output 2 | COM1: ±15VDC @ 1A |
| Output 3 | COM1: +12VDC @ 1A |
| Output 4 | COM5: +24VDC @ 2A |
| Output 5 | COM2: ±24VDC @ 1A |
| Output 6 | COM4: +15VDC @ 2A |
| Operating Environment | High Temp, Humidity, Vibration, EMI Resistant |
| Application | PLC, DCS, Industrial Automation, Telecom |
Product Introduction
When a PLC backplane starts dropping voltage because the power supply is failing, the whole control system turns into a giant paperweight. The ABSOLUTE 80026-173-23 MOX12-P3509 is the exact type of industrial DC-DC power module that keeps the logic cards fed and happy. It takes a messy, wide-range DC input (anywhere from 42V up to 258V) and chops it down into clean, isolated rails for the rest of the chassis.
I’ve pulled a lot of these out of hot, dusty cabinets over the years, and the multi-output design is genuinely useful. Getting a solid 10A on the ±5V rail and dedicated 24V/15V rails means you don’t have to daisy-chain external converters. It’s a tough piece of kit built for high vibration and EMI, though I will say the terminal blocks can get brittle if they’ve been baking at 60°C for a decade. Treat it right, and it’ll keep your DCS humming.
Quality SOP & Tech Pitfalls (The Reality Check)
The Lab Report (SOP)
Power supplies aren’t like logic boards; you can’t just plug them in and hope. Before shipping, we do a visual inspection for blown caps or burnt traces. Then, it goes on the bench power supply for a live load test. We crank up the input to 258VDC and pull maximum current on the 5V and 24V rails to check for thermal runaway. We verify ripple with an oscilloscope, check insulation resistance with a megger, and pack it in anti-static foam with a printed test report.
The Engineer’s Warning (Pitfalls)
Never, ever assume the input voltage is safe just because the label says 258VDC max. I’ve seen a tech accidentally hook up a 480V AC line to a 258VDC-rated module because he was rushing during a weekend shutdown. The resulting explosion took out the backplane fuse and cost two days of downtime. Also, watch out for inrush current. When you power up a system with multiple of these modules, the simultaneous capacitor charging can trip your upstream breakers. Soft-start them if possible, or stagger the power-up sequence.
Installation & Configuration Guide
- Pre-Installation: ⚠️ CRITICAL: Lock out and tag out the main power. Wait at least 5 minutes for the internal capacitors to discharge. Verify 0V with a multimeter before touching anything. Take a photo of the existing wiring.
- Removal: Label every wire with a sharpie or tag. Loosen the terminal screws and pull the wires straight out. Release the DIN rail clips and slide the old MOX12-P3509 off the rail.
- Installation: Slide the new module onto the DIN rail and lock the clips. Double-check the input polarity before applying power. Reconnect the output wires exactly as photographed. Torque the terminal screws to spec—loose connections under high current will melt the terminal block.
- Power-On & Testing: Apply the 42-258VDC input. Check the status LEDs. Use a multimeter to verify each output rail (±5V, ±15V, +12V, +24V) is within tolerance. Monitor the module for 15 minutes to ensure it isn’t running hot.
ABSOLUTE 80026-173-23 MOX12-P3509
Compatible Replacement Models
| Replacement Model | Compatibility Tier | Field Notes |
|---|---|---|
| MOX12-P3509 (Same Rev) | ✅ Drop-in Replacement | 100% pinout and spec match. Direct swap. |
| MOX12-P3509B | ✅ Drop-in Replacement | Minor revision. Verify output pinout matches your chassis. |
| ABSOPULSE Equiv. | ⚠️ Software Compatible | Same manufacturer, different part number. Requires wiring harness adaptation and load testing. |
| Generic 24V PSU | ❌ Hardware Mod Required | Will not work. This is a multi-output DC-DC converter, not a standard 24V supply. |
Frequently Asked Questions (FAQ)
Can I use a standard 24V power supply instead of this?
Absolutely not. This is a multi-output DC-DC converter. Your PLC backplane needs the ±5V and ±15V rails to operate the analog and digital logic cards. A standard 24V supply will leave those cards dead.
Is the 258VDC input limit hard or soft?
It’s a hard limit. Do not exceed 258VDC. If your plant runs on a 480V AC system, you need a step-down transformer and rectifier upstream of this module. Don’t try to feed it raw rectified 480V.
Does this module support hot-swapping?
Generally, no. While the DeltaV controllers support hot-swap, power supplies are usually single points of failure. Plan a scheduled maintenance window to swap this safely. If your system has redundant power supplies, follow the OEM redundancy switchover procedure.
Why are there so many output terminals?
Industrial PLCs need multiple isolated voltage rails. The ±5V feeds the CPU and digital logic, the ±15V feeds analog I/O cards, and the +24V feeds relays and field devices. They all need to be isolated from each other to prevent ground loops.
How do I know if this power supply is failing?
Look for intermittent PLC faults, analog signal noise, or random I/O dropouts. Measure the output rails under load. If the 5V rail is sagging below 4.9V or you see excessive ripple on the oscilloscope, the internal capacitors are likely dried out. Replace it before it takes out the CPU.
Is this module still supported by the OEM?
ABSOLUTE/ABSOPULSE is a legacy brand. These are typically New Surplus or refurbished OEM parts. We test every unit to original specifications, but always keep a spare on the shelf. When they’re gone, they’re gone.
