Key Technical Specifications
| Parameter | Value | Field Note |
|---|---|---|
| Collector Current ( IC ) | 100 A | Max continuous rating at TC=25∘C . Derate above 70°C case temp. |
| Collector-Emitter Voltage ( VCES ) | 600 V | Do not exceed. Snubber circuits are mandatory for inductive loads. |
| DC Current Gain ( hFE ) | 75 (Typ) | Darlington gain reduces base drive current but increases saturation voltage. |
| Saturation Voltage ( VCE(sat) ) | ~2.5 V | Higher than IGBTs. Calculate conduction losses carefully. |
| Package Type | 1U Module | Standard footprint. Check mounting hole torque specs. |
| Isolation Voltage | 2500 VAC | Base plate to terminal insulation. Use thermal compound correctly. |
| Operating Temp ( Tvj ) | 150°C Max | Junction temp. Keep case temp well below this for longevity. |
| Application | Inverters / Drives | Ideal for older servo drives and DC motor controllers. |
Product Introduction
I’ve pulled these QM100HY-H modules out of fried servo drives more times than I can count. They are the workhorses of 90s and early 2000s industrial motion control, sitting right behind the base drive circuit in Mitsubishi inverters and NC equipment. When a machine stops moving and smells like burnt silicon, this is usually the first thing I grab my multimeter for. It’s a Darlington, which means it loves to switch but hates to stay on; the base drive requirements are low, but the conduction losses run hot.Engineers stick with the QM100HY-H because it’s a known quantity. You know exactly how it fails (usually shorted C-E), and you know the base drive resistor values by heart. With a 100A rating and 600V blocking, it handles the dirty work in medium-power switching without needing the complex gate drive logic of modern IGBTs. Just remember: this specific revision is notoriously sensitive to base-emitter reverse voltage. If your snubber is weak or your wiring is long, the inductive kickback will punch through the base junction before the collector even notices.
Quality SOP & Tech Pitfalls
The Lab Report:
We don’t just guess. Every QM100HY-H goes through a strict bench protocol before it ships.
- Visual/Counterfeit Check: Inspect epoxy for re-molding marks, pin corrosion, and laser etching consistency. Fake Mitsubishis are everywhere.
- Live Test on Rack: Installed in a test fixture with active base drive. We cycle it at 50% load to verify switching times and thermal stability.
- Leakage & Gain Check: Fluke 115 for VCE leakage at rated voltage; curve tracer verification for hFE linearity.
- Firmware/Date Code Logging: We record the date code. Old stock can suffer from bond wire degradation.
- Anti-Static Sealing: Vacuum sealed with desiccant. GTRs are ESD sensitive at the base terminal.
The Engineer’s Warning:
Don’t just swap this and power up. I’ve seen guys toast a brand-new QM100HY-H in 3 seconds because they didn’t check the base drive resistors. If the old module failed shorted, those base resistors are likely drifted or open. Test them first. Also, watch the torque on the mounting screws. Over-torquing this 1U package cracks the internal ceramic substrate. I had a customer who cracked three modules in a row because he used an impact driver on the heatsink bolts. Hand-tighten, then torque to spec.
Installation & Configuration Guide
- Pre-Installation Safety: ⚠️ LOCKOUT/TAGOUT. Discharge DC bus capacitors. Wait 5 minutes. Verify 0V with a meter. Take a photo of the base wiring before touching anything.
- Removal: Label the Base (B), Collector (C), and Emitter (E) wires. Unsink the module. Release DIN clips or mounting bolts evenly. Do not pry.
- Installation: Clean the heatsink surface with IPA. Apply fresh thermal compound (thin, even layer). Copy DIP switch/Jumper settings from the old module if applicable. Seat the QM100HY-H squarely. Torque mounting bolts in a cross pattern to 0.8-1.0 N·m.
- Power-On & Testing: Reconnect base drive wires. Double-check polarity. Power up with a variac or current-limited supply if possible. Check for smoke or heat. Verify gate/base waveforms with a scope before applying full load.
Compatible Replacement Models
| Model | Compatibility | Notes |
|---|---|---|
| QM100HY-2H | ✅ Drop-in Replacement | 1000V version. Higher voltage margin, slightly higher VCE(sat) . Direct swap. |
| QM100HY-H | ✅ Exact Match | Original spec. Best for preserving original drive characteristics. |
| QM100DY-H | ⚠️ Software Compatible | Different internal topology (Darlington vs. Single). Requires base drive resistor check. |
| IGBT Module | ❌ Hardware Mod Required | Do not swap directly. Gate drive voltage and timing are totally different. Full redesign needed. |
Frequently Asked Questions (FAQ)
Can I hot-swap this module safely?
Absolutely not. GTRs are not hot-swappable. You risk arc flash and destroying the base drive transistors. Power down, discharge, and verify zero energy.Is the QM100HY-H the same as the QM100HY-2H?
No. The -2H is rated for 1000V, while the -H is 600V. You can use the 2H as a drop-in replacement (it’s overkill on voltage), but never use the -H in a 1000V circuit. It will explode.Why does my base drive keep burning these out?
Check your snubber capacitor. If it’s dried out or has high ESR, the dV/dt spike at turn-off will punch through the base-emitter junction. Also, verify your base drive resistors haven’t drifted high, causing slow turn-off and thermal runaway.How do I know if it’s a fake?
Fakes often have shiny, uneven epoxy or misaligned pins. The laser marking should be crisp and deep. If the price is 50% below market, it’s fake. We test every batch for hFE consistency; fakes usually have wild gain variations.Can I use a standard silicon grease?
Yes, but use high-quality thermal compound, not the cheap white stuff that dries out in a year. For high-reliability apps, consider phase-change pads, but ensure they’re rated for the pressure of the 1U mounting bolts.What’s the max base current I should push?
Don’t exceed 2A peak. The datasheet says 2A for fast switching, but continuous base current should be calculated based on your duty cycle. Over-driving the base just wastes power and heats the junction.Do I need to re-tune the drive after replacement?
Usually no, if it’s an exact QM100HY-H replacement. But if you’re using the 1000V version (-2H), the saturation voltage is slightly higher. Monitor the drive’s thermal load for the first hour. If it runs hotter, you might need to tweak the PWM carrier frequency down slightly.
