Ogemray Smart Relay 25A Review: A High-Power Third-Party Alternative to Shelly Relays

When you need a smart relay capable of handling high-current loads like electric heaters, water pumps, or heavy-duty appliances, the Ogemray Smart Relay 25A presents itself as a compelling option. Designed as a third-party relay alternative, it delivers 25 amps of switching capacity while supporting Wi-Fi connectivity and integration with major smart home platforms. But how does it stack up against established brands like Shelly, especially the popular Shelly 1PM Gen3 and Shelly 2PM Gen4 2-pack? In this review, we dig into the build, features, performance, and overall value of the Ogemray Smart Relay 25A.

The growing demand for high-power smart relays has opened the door for alternatives beyond the well-known Shelly ecosystem. While Shelly offers reliable relays with energy monitoring, third-party options like the Ogemray aim to provide similar functionality at a lower price point. However, choosing a third-party relay requires careful evaluation of reliability, safety certifications, and firmware support. We tested the Ogemray Smart Relay 25A in a real home environment for a week, switching a 3000W water heater and a 2000W workshop heater. Here's what we found.

Overview of the Ogemray Smart Relay 25A

The Ogemray Smart Relay 25A is a compact Wi-Fi relay designed for DIN rail mounting or standalone use. It supports both normally open and normally closed configurations, making it versatile for a variety of applications. The relay can handle resistive loads up to 25A (5500W at 220V) and inductive loads up to 15A, which covers most home heavy-duty appliances. It uses a standard ESP32 chipset, which gives it good compatibility with platforms like Home Assistant, OpenHAB, and even Alexa if you use a custom skill.

What sets the Ogemray apart from many other third-party relays is its built-in web interface for firmware updates and configuration. It also supports MQTT out of the box, allowing advanced users to integrate it into complex automation scenarios. The physical dimensions are similar to a Shelly 1PM Gen3, but the Ogemray is slightly thicker due to a larger heatsink for handling 25A. The relay comes with a one-year warranty and is ETL/CE listed, though we recommend verifying local certifications before installation.

• Rated: 25A resistive / 15A inductive (250V AC max)
• Connectivity: Wi-Fi 2.4 GHz, MQTT, HTTP
• Compatible with: Home Assistant, OpenHAB, ESPHome
• Physical: DIN rail or surface mount, dimensions 44 x 70 x 25 mm

Key Features and Specifications

The Ogemray Smart Relay 25A packs several features that make it attractive for DIY smart home enthusiasts. Most importantly, it includes a real-time power monitoring chip that reports voltage, current, power, and cumulative energy consumption. This data is accessible through the relay's web interface or via MQTT tags. The accuracy is decent but not as precise as the Shelly 1PM Gen3, which uses a more refined metering circuit. For basic energy tracking, the Ogemray is sufficient, but if you need granular data for billing, you might prefer a Shelly relay with calibrated monitoring.

Another standout feature is its support for over-the-air (OTA) firmware updates. During our testing, we updated the firmware twice, and the process was smooth via the web portal. The board also includes a small reset button and a programmable LED indicator. One missing feature, however, is support for local switching without a neutral wire. The Ogemray requires both line and neutral, similar to most smart relays. If you have older homes without a neutral at the switchbox, you would need a Shelly Wall Switch List or a battery-powered solution instead.

• Power monitoring: V, A, W, kWh (accuracy ±5% typical)
• Firmware: OTA updates via web UI
• Safety: Built-in over-temperature and over-current protection
• Ingress: IP20 (indoor use only)

Performance in Real-World Use

We tested the Ogemray with a 3000W water heater and found it switched reliably every time. The relay click is audible, which is normal for mechanical relays of this rating. The internal temperature after one hour of continuous 25A load reached about 55°C, which is within safe limits. The Wi-Fi range was adequate — about 20 meters through two drywall walls. We did notice occasional latency of 1-2 seconds when using MQTT commands, likely due to the Wi-Fi stack. In comparison, the Shelly 2PM Gen4 2-pack responds almost instantly to MQTT thanks to its optimized firmware.

Energy monitoring reported power within 3% of a clamp meter for resistive loads, but for inductive loads like a motor, the readings fluctuated more. The web interface is basic but functional: you can toggle the relay, view real-time data, and set a few automation rules like weekly schedules or react to voltage thresholds. For advanced scripting, you'll want to use ESPHome or MQTT directly. Overall, for the price, the performance is acceptable for high-power applications where a third-party relay is acceptable.

One concern we encountered was that the relay's web interface sometimes became unresponsive after 48 hours of continuous uptime, requiring a power cycle. This seems to be a firmware bug that Ogemray is aware of — an update was released during our testing period. After the update, we had 72 hours of stable operation. This highlights the importance of choosing a product with active firmware support.

Ogemray vs. Shelly: Which Relay Should You Choose?

The natural question is how the Ogemray compares to the industry standard from Shelly. The Shelly 1PM Gen3 is a 16A relay with highly accurate energy monitoring, a proven track record, and broad smart home compatibility. Meanwhile, the Shelly 2PM Gen4 2-pack offers two independent 16A channels in one device, plus even more advanced features like submetering and roller shutter support. Shelly relays are generally more polished in terms of firmware reliability and support for cloud-free local operation.

Where the Ogemray wins is raw current capacity: 25A vs. 16A for most Shelly relays. If you need to switch a 5000W load, the Ogemray is ready out of the box. However, for typical home circuits (lights, fans, small appliances), the Shelly 1PM Gen3 or Shelly 2PM Gen4 2-pack are more refined and easier to integrate. The Ogemray also costs about 30% less than a Shelly 1PM Gen3, making it a budget option for high-power scenarios. But if safety regulations in your project require strict certifications, Shelly's CE/UL marks might be more recognizable to inspectors.

Another consideration is the ecosystem: Shelly offers a mature app (Shelly Smart Control) with cloud and local modes, while the Ogemray relies on third-party platforms (Home Assistant, OpenHAB) for a polished user interface. If you are comfortable with custom integrations, the Ogemray is a viable alternative; if you prefer a plug-and-play experience, stick with Shelly.

• Choose Shelly 1PM Gen3 for accuracy and ecosystem support
• Choose Shelly 2PM Gen4 2-pack for two channels and roller shutter control
• Choose Ogemray for high-power loads (up to 25A) on a budget

Installation Tips and Considerations

Installing the Ogemray Smart Relay 25A requires basic electrical knowledge. The relay comes with a wiring diagram that is printed on the side of the case. You'll need to connect line (L), neutral (N), load (L1), and optionally a momentary switch for manual control. The relay does not have a dedicated input for external sensors, unlike the Shelly Pro 1CB C63A which includes dry contact inputs for thermostats or float switches. If you need sensor inputs, look at Shelly's professional range.

For mounting, the Ogemray includes a DIN rail clip, and it fits in a standard distribution board. However, because of the 25A rating, ensure the wiring (at least 2.5 mm²) and the circuit breaker (ideally 25A C-curve) are properly sized. The relay itself has built-in overcurrent protection that trips at 30A, but it should not be relied upon as the primary circuit breaker. Always follow local electrical codes.

A practical tip: after installation, set up the relay on a separate Wi-Fi SSID if possible, or at least use a static IP to avoid discovery issues. During testing, we found that a DHCP lease renewal sometimes caused the relay to lose connection until it was power cycled. Giving it a fixed IP via your router solved this.

• Use 2.5 mm² or thicker wire for 25A continuous load
• Consider a dedicated 25A MCB upstream
• Assign a static IP in your router for stable MQTT operation

Pros and Cons of the Ogemray Smart Relay 25A

Starting with the positives: the Ogemray offers an unmatched current rating in its price class, reliable switching up to 25A, and basic but useful power monitoring. It is open-platform friendly with MQTT and ESPHome support. The web UI for OTA updates is a nice touch. For users who need a high-power relay and are willing to handle custom integrations, it's a good value.

On the downside, the firmware is not as mature as Shelly's — we encountered a stability issue that required an update. The energy monitoring lacks the precision of the Shelly 1PM Gen3, and the manual control input only supports a toggle switch, not a momentary press for scenarios like smart light switches. The relay also lacks a local REST API emulation mode that some Shelly users rely on for scripting. Lastly, customer support may be slower compared to Shelly's established channels.

Overall, the Ogemray is best suited for hobbyists, makers, and projects where the 25A capacity is essential and budget constraints matter. For mission-critical or professionally installed systems, a Shelly relay like the Shelly 2PM Gen4 2-pack or the Shelly Pro 1CB C63A offers better reliability and support.

The Ogemray Smart Relay 25A fills a specific niche: high-power smart switching at a low price. While it lacks some polish and reliability of mainstream brands, it does the job for basic automation of large loads. If you need a proven, highly accurate relay with energy monitoring for your home, consider the Shelly 1PM Gen3, which offers excellent performance and a seamless integration experience. For a deeper look at all our ratings and to compare specs, visit our store.