{"id":7386,"date":"2025-07-13T17:32:13","date_gmt":"2025-07-13T17:32:13","guid":{"rendered":"http:\/\/iotronx.com\/izdelek\/sonoff-smart-stackable-power-meter-spm-glavna-enota\/"},"modified":"2025-08-07T22:21:31","modified_gmt":"2025-08-07T22:21:31","slug":"sonoff-spm-4-channel-relay-module-main-unit","status":"publish","type":"product","link":"https:\/\/iotronx.com\/en\/izdelek\/sonoff-spm-glavna-enota-4-kanalnega-relejnega-modula\/","title":{"rendered":"Sonoff SPM 4-channel Relay Module Master Unit"},"content":{"rendered":"

Connect up to 32 SPM-4Relays\u3011One SPM-Main unit can connect up to 32 SPM-4Relay modules. Each 4-relay module has 4 isolated channels for easier device management.
\n\u3010Meter your energy consumption\u3011Monitor your energy consumption via the eWeLink mobile app. Easily access current, voltage and power data.
\n\u3010Max. 20A per channel\u3011Each channel supports up to 20A of current, so even larger consumers can be easily handled.
\n\u3010Communication via RS-485\u3011The main unit communicates with relays via RS-485 bus, which enables stable multi-point transmission connection over long distances.
\n\u3010Overload Protection\u3011When enabled, the device effectively prevents overload damage.<\/p>\n

 <\/p>\n

\"Sonoff<\/p>\n

SONOFF Smart Stackable Power Meter<\/strong> consists of:<\/p>\n

(1) main units<\/strong> with built-in Wi-Fi chip and support for eWeLink IoT cloud and eWeLink app, and<\/p>\n

(2) one or more SPM-4Relay 4-channel relay modules<\/strong>.<\/p>\n

\n

THIS PRODUCT IS THE MAIN UNIT.<\/strong><\/span>
SPM 4-RELAY modules are sold separately.<\/strong><\/p>\n<\/blockquote>\n

All units can be mounted on a DIN rail in the electrical cabinet and allow smart management and metering of energy consumption<\/strong> up to 20A per channel. Also built-in overload protection<\/strong>. It is professional high-performance smart solution<\/strong> for managing homes, commercial buildings, industrial buildings or shopping centres to monitor the energy consumption of occupants or tenants.<\/p>\n

\"SPM<\/p>\n

The main unit connects to the eWeLink cloud via Wi-Fi or Ethernet. Communication with the relays is via an RS-485 bus, allowing reliable long-term operation. One master unit can control up to 32 four-channel modules (128 channels of 20A in total), each with independent power metering and control.<\/p>\n

The unit has an SD card slot (not attached<\/em>), where you can insert an 8-32 GB SDHC card to store up to 180 days of consumption data. You can also retrieve and export data via HTTP API.<\/p>\n

Linking SPM units - diagram:<\/strong><\/h3>\n

\"Sonoff<\/p>\n

Main product features:<\/strong><\/h3>\n
    \n
  • Remote on\/off<\/strong> - control channels anywhere, anytime via the internet.<\/li>\n
  • Up to 32 x 4-channel relays can be added<\/strong> - up to 128 independent channels in total.<\/li>\n
  • DIN rail mounting<\/strong> - Ideal for junction boxes and industrial use.<\/li>\n
  • SD card support<\/strong> - up to 180 days of consumption data storage (8-32 GB SDHC card).<\/li>\n
  • Independent channel management<\/strong><\/li>\n
  • Physical buttons<\/strong> on\/off switch on each 4-relay module<\/li>\n
  • Overload protection<\/strong> on all channels<\/li>\n
  • eWeLink mobile app<\/strong> - for Android and iOS, connection to eWeLink Cloud<\/li>\n
  • Display current status<\/strong> - check the status of the relays (on\/off) in the app<\/li>\n
  • Sharing control<\/strong> - allow access for multiple users (e.g. family, colleagues)<\/li>\n<\/ul>\n

    \"Technical<\/p>","protected":false},"excerpt":{"rendered":"

    Sonoff's Smart Power Meter (SPM) is a professional grade, DIN-scale compatible, stackable relay with power meter and overload protection, with a maximum capacity of up to 20 A per channel. Power consumption can be stored on a memory card (not an accessory).<\/p>","protected":false},"featured_media":7388,"template":"","meta":{"_acf_changed":false},"product_brand":[120],"product_cat":[136,91],"product_tag":[],"class_list":["post-7386","product","type-product","status-publish","has-post-thumbnail","product_brand-sonoff","product_cat-ewelink","product_cat-nadzor-porabe-energije","first","instock","sale","taxable","shipping-taxable","purchasable","product-type-simple"],"acf":[],"_links":{"self":[{"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/product\/7386","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/media\/7388"}],"wp:attachment":[{"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/media?parent=7386"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/product_brand?post=7386"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/product_cat?post=7386"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/iotronx.com\/en\/wp-json\/wp\/v2\/product_tag?post=7386"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}