RB-212DMF5 Power Relay for Antminer S19 APW12 Power Supply
Couldn't load pickup availability
Have questions about this product? Our team is here to help — just reach out on WhatsApp.
💬 Contact Us on WhatsAppAbout the Product
RB-212DMF5 Power Relay | 12VDC DPST 8A / 277VAC for Antminer S19 APW12 PSU Repair
The RB-212DMF5 is a general-purpose power relay used on the Antminer S19 APW12 power supply. 12VDC coil driven by the PSU control circuit, DPST (double-pole single-throw) contact configuration, 8A switching capability at 277VAC. The 5000VAC dielectric strength between coil and contacts provides robust isolation between the PSU control side and the mains-switched load.
Drop-in replacement when the original relay fails — common failure modes include welded contacts after extended high-current duty, open coil after thermal stress, or sluggish actuation from contact erosion. A fresh RB-212DMF5 restores the PSU's mains-switching stage to spec.
When to Replace the RB-212DMF5
- PSU fails to start — relay contacts stuck open, mains never reaches the bridge rectifier.
- Audible relay chatter at startup — coil voltage marginal or relay actuator failing.
- Welded contacts — PSU stays powered after the control signal releases, won't shut down cleanly.
- Visible damage on the relay housing — burnt body or melted plastic after a fault event.
- Coil open-circuit reading on a DMM with the relay isolated — winding failed internally.
RB-212DMF5 Power Relay Specifications
| Feature | Specification |
|---|---|
| Part Number | RB-212DMF5 |
| Product Category | General purpose relay |
| Coil Voltage | 12VDC |
| Contact Form | DPST (Double Pole Single Throw) |
| Contact Current Rating | 8A |
| Switching Voltage | 277VAC |
| Nominal Power | 0.4W at 20°C |
| Coil Resistance | 360Ω ±10% at 20°C |
| Nominal Current | 33.3mA ±10% at 20°C |
| Operate Voltage | 9VDC max at 20°C |
| Release Voltage | 0.6VDC min at 20°C |
| Max Coil Voltage | 18.6VDC (155% of nominal) |
| Dielectric Strength (coil-contacts) | 5000VAC |
| Temperature Range | -40°C to 105°C (no condensation) |
| Humidity Range | 20% to 85% RH (no condensation) |
| Compatible PSU | Antminer S19 APW12 |
FAQ — RB-212DMF5 Power Relay
Q: How do I test the relay in-circuit?
A: Power off the PSU. Measure coil resistance with a DMM — healthy reads ~360Ω. Open circuit = failed coil, replace. Then check contact continuity in the relaxed state (normally open) — should be OL until 9VDC+ applied to the coil.
Q: Standard vs sensitive coil variant — which one for APW12?
A: The APW12 uses the standard coil version. Sensitive coil variants exist for low-power drive applications but don't match the APW12 control-circuit voltages. Match the part number exactly.
Q: Replacement procedure?
A: Desolder the through-hole pins on the PSU control board, clean the holes, fit the new RB-212DMF5 with correct orientation (coil pins vs contact pins clearly marked on the housing), reflow. Test coil resistance before powering up the PSU.
Q: Bulk pricing for APW12 PSU repair benches?
A: Yes — email contact@lys-sz.com for volume pricing on RB-212DMF5 stock.
Related products
- APW12 Power Supply (Antminer L7 / S19j)
- DFB2560 Bridge Rectifier 600V (APW12 PSU)
- HF32F-G/012-HS High-Power Relay (Whatsminer)
- Antminer APW12 PSU Test Fixture
APW12 PSU repair benches stocking RB-212DMF5 relays by the tray? Email contact@lys-sz.com for bulk pricing. Worldwide shipping from our Shenzhen warehouse.
Buying in bulk for a mining farm or repair shop?
Get dedicated B2B pricing on this part and across our full catalog — quote response within 24 hours, payment by T/T USD bank wire, and DDP delivery available for US & EU customers (and other lanes on request).
