Last Updated: September 27, 2026
Quick Answer: For this worked example, a verified 230VAC installation has a 24V control load of 6.0A, or 144W. The EDR-150-24 is supported at 24V/6.5A for that input condition, so it passes the first arithmetic screen. That result is not final approval: peak current, ambient derating, voltage drop, protection, exact product revision, and commissioning still have to be verified.
An automatic cold-storage door may have a large motor, but its 24V control power supply should not be sized from the motor nameplate. In the architecture discussed here, the motor is powered by a separate drive. The DIN-rail supply serves only the control loads: PLC, HMI, remote I/O, safety sensors, relays and contactor coils, an electric lock or brake-release device, status indication, and communications equipment.
That boundary matters. Adding motor power to the control calculation produces the wrong architecture, while overlooking a lock coil or a simultaneous alarm state can produce an undersized 24V supply. This worked example maps a 6.0A worst-case control state and then checks it against the input-dependent ratings in the current WEHO EDR-150 specification sheet.
The result is deliberately specific: the EDR-150-24 can pass this first-stage 6.0A comparison at a verified 230VAC input, where the available WEHO sources agree on a 24V/6.5A operating point. This article does not extend that conclusion to other input conditions because the input-range statements differ across the product page, technical sheet, and photographed label.
Build the load map around operating states
Do not add only normal running currents. Define the door states first: closed and locked, unlock command, opening, open hold, closing, safety reversal, alarm, and restart after a power interruption. Then identify which control devices can be energized together.
An illustrative maximum-concurrent schedule for a 230VAC installation could be:
| 24V control-load group | Example maximum simultaneous current | Power at 24V |
|---|---|---|
| PLC, HMI, and remote I/O | 1.30A | 31.2W |
| Safety sensors and limit switches | 0.50A | 12.0W |
| Relay and contactor coils | 0.90A | 21.6W |
| Electric lock and brake release | 1.50A | 36.0W |
| Status beacon and sounder | 0.40A | 9.6W |
| Panel accessories and communications | 1.40A | 33.6W |
| Total | 6.00A | 144.0W |
These are example values, not ratings for a particular door. A real project must replace every row with the selected device datasheet value and confirm the credible overlap between loads. The motor and its drive remain outside this 24V control calculation.
The most demanding state may occur during a transition rather than normal travel. The lock-release device, selected relay or contactor coils, safety sensors, warning beacon, HMI, PLC, and gateway may operate together during unlock, reversal, alarm, or restart. A state-based load map is therefore more useful than a list of connected devices.
Why the EDR-120-24 is too small for this example
The WEHO EDR-120-24 is listed at 24V and 5A. The defined control state requires 6.0A, so that model is already short by 1.0A before pull-in current, ambient derating, conductor voltage drop, or future changes are considered.
The current EDR-150 sheet lists the EDR-150-24 at 24V/6.5A for 230VAC input, and the photographed unit label and WEHO EDR-150 product page support the same 24V/6.5A operating point. At the verified 230VAC site supply, the 6.0A example leaves 0.5A, equivalent to 12W at 24V. It therefore passes the first arithmetic screen.
This illustrative close-up shows the source-controlled EDR-150-24 from a straight-on front view inside an open refrigerated loading-bay control cabinet, with the freezer door and material-flow zone providing application context. The native blue face, -V/-V/+V/+V and protective-earth/N/L terminal order, and 40 × 125.2 × 113.5 mm envelope are checked against the source photograph and current specification. The front-on view intentionally keeps the unverified side warning panel out of sight; the 24V control supply remains distinct from the separate door-motor path.
This conclusion is intentionally narrow. The remaining 0.5A is not automatically an adequate engineering margin, and passing a nameplate comparison is not final proof of suitability. The current product sheet, ordered revision, installation conditions, dynamic current, branch protection, and commissioning results still govern the decision.
Reconcile the exact product revision before release
The product page, current enterprise-drive sheet, and photographed label all identify the EDR-150-24 and support the 230VAC/24V/6.5A point used here. The specification’s front, side, and overall-dimension views identify a 40mm width, 125.2mm height, and 113.5mm depth. Use those outside dimensions for a preliminary cabinet-space check; they do not establish the required installation clearances. Confirm rail position, cable bend space, and ventilation clearance against the ordered revision before finalizing the enclosure.
Their published input-range wording is not identical, which indicates that online data, specification sheets, and photographed labels may represent different revisions. This worked example therefore uses only the shared 230VAC/24V/6.5A point. For any other input condition—or whenever the ordered unit, product page, and current sheet do not align—stop and obtain confirmation for the exact model and revision. Never combine the most favorable value from each source.
Check pull-in and startup behavior
Relay coils, contactor coils, locks, and brake-release devices can draw more current during pickup than while holding. An HMI, gateway, or distributed I/O assembly can also have a startup profile that is not obvious from its average consumption.
For each load, obtain peak current, peak duration, repetition rate, and permitted voltage dip. Determine whether peaks can overlap during unlock, reversal, alarm, or power restoration. If the supplier data does not define the dynamic behavior clearly, measure it in a representative panel and observe the 24V bus at the load terminals. A steady 6.0A calculation alone cannot prove acceptable transient performance.
This second application image shows the source-controlled EDR-150-24 inside an open OEM cold-room door validation panel while an engineer measures the full actuator rig. The exact front label, four upper -V/-V/+V/+V terminals, three lower protective-earth/N/L terminals, and 40 × 125.2 × 113.5 mm envelope are checked against the source photograph and current specification. A closed auxiliary junction/protection box keeps surrounding connections covered; the illustrated 24V control path remains separate from the door-motor path.
Design the cabinet for the real environment
A cold room does not necessarily mean the power supply operates in cold, dry air. A sealed cabinet can become warm internally, while door openings, washdown, and temperature cycling can create condensation risk around the installation.
Verify the actual cabinet ambient temperature, enclosure construction, mounting clearances, airflow, neighboring heat sources, and the manufacturer’s derating requirements. Provide the environmental protection required by the project; the product’s electrical rating alone does not establish suitability for direct water, condensation, or washdown exposure.
Calculate voltage drop to moving and remote loads
The control cabinet may be several metres from the lock, door-position sensors, beacon, or sounder. Flexible door cable, connectors, and terminal blocks add resistance. Calculate voltage drop over the complete outgoing-and-return conductor path at the highest credible branch current.
Confirm that the farthest device remains within its permitted voltage range during simultaneous loading and pickup. Do not use the power supply’s voltage adjustment as a substitute for correctly sized conductors, sound terminations, and a verified voltage-drop budget.
Coordinate protection and keep the motor path separate
Divide the 24V distribution into documented branches where appropriate, and select protection according to conductor ampacity, load behavior, available fault current, and the required fault response. Review suppression for inductive coils, grounding and bonding, polarity, terminal ratings, and whether one branch fault could remove PLC or safety-sensor power.
The motor drive must remain on its own engineered power path. The EDR-150-24 in this example supplies the 24V control bus; it is not depicted or selected as the door-motor source.
Commission the worst operating case
Before release, test the assembled panel through repeated unlock, open, close, reversal, alarm, and restart sequences. Record supply-terminal voltage, farthest-load voltage, peak current, cabinet temperature, and recovery after transient events. Repeat relevant tests after the cabinet reaches its expected thermal condition and under the specified input supply.
For procurement or engineering review, provide the exact load BOM, operating-state matrix, peak-current data, cable lengths and conductor sizes, ambient and enclosure conditions, upstream protection, input voltage, and applicable local requirements. That evidence gives a much stronger basis for confirming the EDR-150-24 than the phrase “150W power supply” alone.
Key Takeaways
- Keep the automatic-door motor and its drive outside the 24V control-load calculation.
- The example control state totals 6.0A at 24V, or 144W.
- The 5A EDR-120-24 is too small for that stated control load.
- At the verified 230VAC input, the EDR-150-24’s 6.5A operating point passes the first arithmetic comparison, leaving 0.5A or 12W.
- The source revisions differ in their broader input-range wording, so this conclusion must not be generalized beyond the shared 230VAC/24V/6.5A point.
- Peak current, thermal derating, cable voltage drop, branch protection, ordered revision, and commissioning results still govern final approval.
Conclusion
For the worked 230VAC case, the logic is clear: the 5A EDR-120-24 is too small, while the EDR-150-24 can cover the stated 6.0A steady control load at the first screening stage. This is an evidence-bound selection, not a reusable default. Change the input voltage, load overlap, temperature, wiring, or product revision, and the decision must be run again.
Frequently Asked Questions
Can the EDR-150-24 power the 6.0A load in this example?
At the verified 230VAC input used by this example, the current WEHO specification sheet lists 6.5A for the 24V model, so it passes the initial 6.0A steady-current comparison. Final suitability still depends on peak current, derating, temperature, voltage drop, protection, the exact ordered revision, and commissioning tests.
Why is the EDR-120-24 not selected?
The EDR-120-24 is listed at 24V and 5A. The example requires 6.0A, so the load already exceeds that rating before any other engineering checks are applied.
Does the 6.0A calculation include the automatic door motor?
No. The motor is powered by a separate drive. This article covers only the 24V control bus and its PLC, HMI, I/O, sensors, coils, lock or brake release, indication, and communications loads.
Can this 230VAC example be reused for another input voltage?
No. The product page, technical sheet, and photographed label do not use identical input-range wording. This article relies only on their shared 230VAC/24V/6.5A operating point. Confirm the exact ordered revision and repeat the selection for any other input condition.
What should be checked before approving the BOM?
Confirm exact device currents, overlapping operating states, startup and pull-in peaks, input voltage, cabinet temperature and derating, conductor voltage drop, branch protection, coil suppression, product revision, installation instructions, and applicable local requirements.
