The power supply is one of the most overlooked — and most critical — components in an industrial computer. While office computers plug into a standard wall outlet, industrial systems must operate reliably from unpredictable, variable, and sometimes hostile power sources.
The Problem with Standard Power Supplies
Consumer computer power supplies (ATX) are designed for one thing: converting clean 110/220V AC from a wall outlet to the DC voltages the motherboard needs. They assume:
- Stable voltage within ±10%
- Clean sine wave with minimal harmonics
- Ground fault protection via building wiring
- Consistent frequency (50/60 Hz)
In industrial environments, none of these assumptions are safe.
Challenges in Industrial Power
Voltage Sags and Surges
Heavy machinery starting up can drop facility voltage by 10-20%. Conversely, when large motors stop, voltage spikes can occur. Industrial power supplies must handle voltage variations of ±20% or more.
DC Power Sources
Many industrial deployments run on DC power:
- Vehicle systems: 12V (cars), 24V (trucks/buses), 48V (heavy equipment)
- Solar/battery installations: 12-48V DC
- Industrial control cabinets: 24V DC (standard for PLCs)
- Telecom: -48V DC
Industrial computers with wide-range DC input (e.g., 9-36V or 12-48V) can operate directly from these sources without external converters.
Transient Voltage Spikes
Vehicle power systems are especially hostile — load dumps when alternators disconnect can produce spikes up to 100V on a 12V system. Industrial vehicle computers include transient voltage suppression rated to ISO 7637 or MIL-STD-1275.
Power Interruptions
Brief power interruptions (brownouts, transfer switch gaps) can crash unprotected systems. Industrial computers include:
- Hold-up capacitors that maintain power through brief interruptions
- Supercapacitor-based UPS for graceful shutdown
- Ignition control for vehicle applications (delayed on/off with configurable timers)
Key Power Supply Specifications
| Specification | Consumer | Industrial |
|---|---|---|
| Input Voltage | 110-240V AC | 9-36V DC or 12-48V DC |
| Voltage Tolerance | ±10% | ±20% or wider |
| Surge Protection | Basic (MOV) | TVS diodes, input filtering |
| Operating Temp | 0-40°C | -20°C to 70°C |
| Hold-Up Time | <20ms | 50-100ms+ |
| Isolation | Basic | Reinforced (1500-3000V) |
| Efficiency | 80-90% | 85-95% |
| Certifications | UL/CE | UL/CE, E-Mark, EN 60950 |
Vehicle Power: Special Considerations
Vehicle-mounted industrial computers need additional features:
- Ignition sensing: Start the computer when the ignition turns on, shut down gracefully when it turns off
- Delayed shutdown: Keep running for a configurable period after ignition off (completing data writes, uploading logs)
- Cold crank protection: Maintain operation when the battery voltage drops during engine starting (can dip to 6V on a 12V system)
- Load dump protection: Survive high-voltage transients when the alternator disconnects
Acnodes Corporation offers industrial computers with wide-range DC power input, vehicle power compatibility, and industrial-grade power protection. Contact us for power design guidance.