Bel Power LWN1902-6 | 1.9kW Rack Rectifier Specs

Description

Product Introduction

DC plant upgrades rarely fail on the rectifier you planned for — they fail on the one that doesn’t fit the shelf. The LWN1902-6 is a Melcher-lineage rack rectifier now sold under Bel Power, built to feed 48V DC distribution in telecom huts and industrial cabinets. Order by the full model string; the LWN family has enough near-twins that a partial code gets you the wrong cassette.

Against the earlier LWN1700-class units, this one delivers roughly 1.9kW in the same rack footprint and runs hotter before derating kicks in. Efficiency sits around 90% at nominal load per Bel’s curve — measured figures vary with input voltage and ambient, so check the datasheet for your operating point rather than trusting the headline number.

Key Technical Specifications

Compatible Replacement Models

• ✅ Drop-in Replacement: Same LWN1902-6 model — cassette swap, no rewiring. Verify output trim matches the existing plant setting.
• ⚠️ Software Compatible: Other LWN1902 revisions and LWN1700-class units — same rack form factor in most cases, but output trim, alarm signaling, and controller handshake may need reconfiguration. Budget 1–2 hours with a DC power tech.
• ❌ Hardware Incompatible: Flatpack and Cassette-series rectifiers with different shelf depth or connector pinouts — new shelf required. Don’t force it.

Frequently Asked Questions

Can I swap this rectifier with the plant live?
Only if your shelf supports hot-swap and the plant has N+1 redundancy. Confirm the cassette connector is rated for live insertion — older Melcher shelves vary. When in doubt, isolate the shelf.

How do I verify the unit works before it ships?
Ask for the test record: AC input sweep, full-load burn-in past 24 hours, output ripple measurement, alarm signaling check, and insulation resistance above 10MΩ. QC Passed tag and anti-static or foam-packed shipping.

Is this the same as a Melcher LWN1902-6?
Yes — Bel Power absorbed the Melcher line, and the model string carried over. Label branding differs by production date; the electrical spec is the same family. Confirm the label photo before buying.

What output voltage should I set?
Match the existing plant float voltage — typically 53.5V for 48V telecom strings, but verify against your battery manufacturer’s data. A wrong trim setting cooks batteries slowly, and nobody notices for a year.

Do the alarm and signaling pins match my rack controller?
Usually, within the LWN family. Cross-generation swaps sometimes move the signal pinout — check the wiring diagram against your controller manual before energizing.

What warranty is reasonable?
A tested-functional guarantee with a defined window: 30 days standard, 90 on some refurbished lots. If the fan sounds rough or the output trim drifts on arrival, flag it before installation.

Any installation traps?
Two. First, airflow direction — these cassettes are front-to-back, and reversing them in a cabinet designed for side-exhaust causes thermal shutdown. Second, leave headroom on the DC distribution; running a rectifier at 100% of rated load shortens capacitor life noticeably.