When you're comparing industrial power supplies transformers, the 12V output is often the starting point. But as you narrow it down, the real decision is about where the supply will be installed and how much current your load draws. Should you choose a DIN rail unit with status signaling and adjustable voltage, or a purpose-built access control supply with a built-in delay? This head-to-head pairs the MEAN WELL MDR-100-12 DIN Rail Power Supply with the 3A 12V Power Supply Control for Door Access Control. One is a general-purpose workhorse; the other is a specialized unit for a specific job. The right pick depends on your mounting situation, your current draw, and whether you value extra control features or a lower upfront cost.
Quick Verdict
The MEAN WELL is the more capable unit for industrial panels, while the 3A access control supply is the targeted solution for a single door. The choice comes down to how much flexibility you need and how much you want to spend.
Product Comparison
Here's how the two supplies stack up on the key specs.
| Feature | MDR-100-12 DIN Rail Power Supply | 3A 12V Door Access Control Power Supply |
|---|---|---|
| Price | $29.99 | $12.55 |
| Output Current | 7.5A | 3A |
| Output Power | 90W | 30W |
| Mounting / Application | DIN rail | Door access control |
| Adjustability | Voltage | Delay (0-15s) |
| Extras | DC OK signal, LED indicator | Pluggable green terminal block |
Where Each Product Wins
MEAN WELL MDR-100-12 wins when the power supply is going to be part of a larger control setup and you expect to change loads over time. The extra capacity gives you room to add sensors, relays, or controllers without swapping the supply.
3A 12V Door Access Control Power Supply wins when the wiring is simple and the load is fixed. It's a self-contained option that keeps the wiring tidy.
MDR-100-12 DIN Rail Power Supply
The MDR-100-12 is a 12V, 7.5A, 90W enclosed DIN rail supply with a white plastic housing. It offers adjustable voltage, an LED indicator, and a DC OK signal-comforting features when you're relying on a continuous 12V bus. The unit is built for indoor installation, and the DIN rail format makes it easy to mount in a standard cabinet. At roughly 100mm deep and 90mm high, it fits typical DIN rail cabinets but does need a little room for ventilation. The main drawback is the power headroom: 7.5A is plenty for many loads, but if your system only draws 1A, you're carrying capacity you won't use.
3A 12V Power Supply Control for Door Access Control
This grey unit is purpose-built for door access hardware. It accepts 110-240V AC and outputs 12V DC at 3A with 30W of power, and it includes an adjustable delay from 0 to 15 seconds as well as a pluggable green terminal block. The delay is especially useful for timed release of electric strikes. The trade-off is the 3A limit: you won't be able to power multiple heavy-duty locks or a high-draw controller from this single unit. On the plus side, the pluggable terminal block makes wiring quick, and the metal and copper construction feels solid for a device that will likely be mounted inside a door access enclosure. For a basic single-door installation, it's a compact and ready-to-use option.
Final Choice by Use Case
For a control cabinet or multi-device setup: Go with the MEAN WELL MDR-100-12. Its higher capacity and flexible output make it a solid foundation for a growing system.
For a single door access install: Go with the 3A power supply control. It's a dedicated, no-fuss source for an electric lock.
If you expect to expand later, the MEAN WELL's extra headroom is worth the investment. If you're just locking one door, the access control unit keeps the project simple.
