When you're choosing between industrial power supplies and transformers for a DIN rail cabinet, the first fork is voltage. The MEAN WELL MDR-100-12 is built around 12V at 7.5A and sells for USD 29.99. The NDR-120-24 is built around 24V at 5A and sells for USD 44.99. Both are DIN rail units, but the way you use the cabinet determines which one actually fits.
Before choosing, think about what you're powering. 12V is common for sensors, small contactors, and control logic, while 24V is often used for valves, actuators, and relay circuits that need a bit more drive. The output current matters too: the MDR supplies 7.5A at 12V, and the NDR supplies 5A at 24V. That means each is sized for a different load profile rather than being a simple substitute. The table below shows the core differences; the sections after it apply those differences to cabinet decisions.
Quick Verdict
If your controls run on 12V, the MDR-100-12 packages adjustable voltage, an LED indicator, and a DC OK signal in an indoor-focused DIN rail unit. If your output devices run on 24V, the NDR-120-24 is the one to pair with them. Let your load voltage drive the decision; the rest is mostly installation environment.
Comparison Table
| Spec | MEAN WELL MDR-100-12 | NDR-120-24 |
|---|---|---|
| Output | 12V DC, 7.5A | 24V DC, 5A |
| Installation area | Indoor | Indoor/Outdoor |
| Price | USD 29.99 | USD 44.99 |
Where Each Wins
After you lock in voltage, look at where the cabinet will live. If the panel stays inside, the 12V unit keeps things simple. If the cabinet may sit outside or in an exposed area, the 24V unit's broader installation area starts to matter more.
- The MEAN WELL MDR-100-12 is the straightforward pick for a 12V control system.
- The NDR-120-24 is the pick for a 24V system.
Product Notes
MEAN WELL MDR-100-12 DIN Rail Power Supply
The MDR-100-12 is the 12V, 7.5A DIN rail supply in an enclosed white housing. It lists an indoor installation area, an adjustable voltage range, an LED indicator, and a DC OK signal. For a control cabinet with 12V sensors or logic circuits, this unit gives you the output you need plus status feedback that helps during commissioning. The limitation is the indoor-only installation area: if the cabinet may be exposed to outdoor conditions, this is not the right unit for that location. Inside a clean, dry panel, that constraint is easy to live with.
NDR-120-24 DIN Rail Power Supply
The NDR-120-24 is the 24V, 5A DIN rail supply with a listed indoor/outdoor installation area and a DIN Rail Mount style. When your actuators, valves, or PLC I/O need 24V, this unit matches the load and gives you more flexibility about where the cabinet can live. The limitation is the higher price and the fit: if your panel is 12V and stays indoors, you'll be paying for a 24V output and an installation area you don't need. For a 24V cabinet in a potentially exposed location, the added cost is harder to argue with.
Final Choice by Use Case
- 12V sensors and indoor controls: MEAN WELL MDR-100-12. It gives you 12V at 7.5A with adjustable voltage and status indicators.
- 24V actuators or devices: NDR-120-24. It gives you 24V at 5A for the devices that need it.
