WESTINGHOUSE 5X00501G01 | Power Supply for WDPF Racks

Description

Product Introduction

That coal-fired plant in West Virginia—the one with the WDPF system that’s been running since the 80s—had a unit trip last fall. The investigation pointed to a “loss of DC” alarm that lasted 200 ms. Long enough for the control relays to drop out, long enough for the burner management system to get confused. The root cause? A 5X00501G01 power supply with a bulging input capacitor. It had been slowly drying out for years, finally couldn’t hold up during a brief AC sag. One 200 part, one 50,000 outage.

The WESTINGHOUSE 5X00501G01 is a 120W power supply module designed to live in WDPF I/O racks and cabinets. It takes 115 or 230V AC (there’s a little selector switch on the side—easy to miss) and gives you a stiff 24V DC at up to 5 amps. Inside, it’s a linear supply? No—switchmode, but built like a tank: through-hole components, big electrolytics, a hefty transformer. It’s not efficient by modern standards (maybe 75%), but it’s rugged. The 5X00501G01 powers the backplane, the field I/O modules, and sometimes the field instruments themselves. In a WDPF system, it’s the heart—if it fails, the whole rack goes dark.

Key Technical Specifications

Quality Inspection Process (SOP Transparency)

A power supply this old needs careful handling. Here’s our SOP.

1. Incoming Verification
   • Match the model: 5X00501G01. (There’s a -G02 variant with different output current—check the label.)
   • Visual inspection: Open the case (if possible) and look for bulging capacitors, brown discoloration on the PCB.
   • Check the input voltage selector switch—make sure it’s not stuck or corroded.
   • Inspect the output terminals—no cracks, screws turn freely.
2. No-Load Test
   • Set the input switch to 230V (unless customer specifies 115V).
   • Apply power through a variac, bring up slowly—watch for sparks.
   • Measure output: 24.0V ±0.5V.
   • Green LED on.
3. Full-Load Test
   • Connect an electronic load at 5A.
   • Run for 1 hour, logging output voltage every 5 minutes.
   • Voltage must stay above 23.5V, ripple <50 mV.
   • Measure case temperature—should stabilize below 65 °C.
4. Protection Test
   • Short the output briefly—the internal fuse should blow (or the supply should go into hiccup mode; we document which).
   • If fuse blows, we replace it (and note in the report).
   • Overvoltage test: force an internal fault (simulated), verify crowbar fires.
5. Isolation Test
   • 500V megger between AC input (shorted) and DC output (shorted)—>10 MΩ.
   • 500V megger between DC output and chassis ground—>10 MΩ.
6. Thermal Soak
   • 4 hours at 50 °C in a thermal chamber, running at 5A load.
   • Monitor output voltage and ripple—must stay within spec.
7. Final QC & Packaging
   • QC sticker with test date and operator initials.
   • Wrap in anti-static bag.
   • Double-box with foam padding—these are heavy units.
   • Test report included—load test log, ripple measurements.

Field Replacement Pitfalls

I’ve swapped these in coal plants, gas plants, and even a nuclear facility. Here’s where people go wrong.

❗Input Voltage Switch
The little red switch on the side is easy to bump during installation. If it’s set to 115V and you feed it 230V, the supply will die instantly—input fuse blows, maybe more. Check it before you apply power. Every time.

Output Polarity
The terminals are marked + and -, but if you reverse them, the supply might have reverse polarity protection? Some do, some don’t. The 5X00501G01 doesn’t—you’ll blow the fuse. Wire it right the first time.

Grounding
There’s a chassis ground terminal. Use it. If you don’t, the output common can float relative to ground, causing noise in the I/O modules. In one plant, an ungrounded supply caused random analog input shifts for years before someone found it.

Load Sharing
If you need more than 5A, you might parallel two supplies. But they’re not designed for active load sharing—you’ll need external OR-ing diodes. Don’t just wire them in parallel; one will carry most of the load and overheat.

Aging Capacitors
These supplies are old. Even new-old-stock units may have capacitors that have degraded from sitting. We reform them during test (gradual power-up), but if you install one that’s been on a shelf for 20 years without reforming, it might fail early.

Nail these five, and your 5X00501G01 will run for another decade.

New Original vs. Refurbished: Why It Matters

“New Original (New Surplus)” means this supply was manufactured by Westinghouse, packed in its original box, and never installed. The capacitors have zero hours (though they may need reforming), the transformer has never been energized, and the terminals have never seen a screwdriver.

Refurbished risk in plain terms
A refurbished Westinghouse power supply often comes from a decommissioned plant. It may have run for years at high temperature. The capacitors are aged—ESR rises, ripple increases. A refurbisher tests it at low load and sells it. Six months later, in a hot cabinet, it fails.

Real cost of a refurbished failure
If this supply powers a critical WDPF rack, a failure means that rack goes dark. If that rack controls a boiler feed pump or a turbine valve, you’re looking at a unit trip. The cost of one forced outage dwarfs the price difference.

What we provide as proof

• Westinghouse box (or photos).
• Serial number recorded.
• Load test log (1 hour at 5A).
• Capacitor reforming note (if applicable).
• 12‑month warranty.

Pricing context
We’re priced 40% above the cheapest “pulled” WDPF supplies and 30% below the original Westinghouse list price (adjusted for inflation). That pays for the full-load test, the capacitor reforming, and the warranty that covers replacement if a capacitor fails.

Performance Benchmarks & Test Results

Test conditions: 230V AC input, 5A load, ambient 24 °C.

We keep the full load test log—ask, and we’ll email the Excel file.

DS2020PDMAG5 GE IPCDCS
DS2020PDMAG6 GE IPCDCS
DS2020SVSAG2 GE DCS
DS2020UCOCN1G1A GE PLC
DS2020UCOCN4G1A GE PLCPLC
DS213SPICNDEVCOM GE DCS