STEP 1
List the connected devices
Record every PoE device and its maximum published power requirement.
Power planning guide
How to Plan the DC Power Supply for an Industrial PoE Switch
The DC supply has to support two separate loads: the switch itself and the PoE power delivered to connected devices. Start with each device's maximum specified power requirement, not the number of available PoE ports alone.
Reviewed by the ERAITOK technical team · Updated 14 September 2026
Connected-device schedule
Start with the devices, not the port count
Prepare a simple device schedule before selecting the switch or power supply. Use the maximum published requirement for each device rather than its normal or average consumption.
- Device type and quantity
- Required PoE standard
- Maximum specified power input
- Whether every device will operate at the same time
- Any ports intended for future expansion
Five-step review
Check the connected load, switch and installation together
STEP 2
Calculate the combined load
Add the maximum power requirements of the connected devices.
STEP 3
Check the switch limit
Confirm that the result remains within the selected switch's published PoE budget.
STEP 4
Include switch consumption
Add the switch's own consumption when sizing the external DC supply.
STEP 5
Confirm the installation
Check DC voltage, current capacity, cabinet conditions and site protection before ordering.
A switch with enough ports is not automatically suitable if the total connected load exceeds its available PoE budget. Any additional design allowance, environmental derating and protective equipment should be checked against the power-supply manufacturer's data and the project electrical design.
ERAITOK product information
Use the figures published for the selected model
ERAITOK publishes model-specific input-voltage ranges, port configurations and PoE budgets on its product pages and English datasheets. Do not apply the figures from one model to another.
Project enquiry
What to include for a useful configuration review
ERAITOK can compare the project requirement with the published product data. Final power-supply selection, enclosure protection and site electrical design remain part of the project specification.
Request a Preliminary Configuration Review- Connected-device types and quantities
- Maximum power requirement per device
- Proposed switch model, if already selected
- Available DC supply voltage
- Copper, SFP or SC fibre connection requirement
- Cabinet and installation conditions
- Required quantity and delivery region