{"product_id":"yokogawa-mro-234-a-spdt-relay-output-module","title":"Yokogawa MRO-234*A SPDT Relay Output Module","description":"\u003cp\u003eThe \u003cstrong\u003eYokogawa MRO-234*A\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003eMRO-234\u003c\/strong\u003e SPDT Relay Output Module, operates as a dedicated hardware component for galvanic isolation and digital contact switching execution within Yokogawa DCS control networks. It accepts low-voltage control signals to actuate Single Pole Double Throw (SPDT) electromechanical contacts, interfacing logic controllers directly with field actuators, solenoids, and alarm indicators across discrete control loops.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMRO-234\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eBase module series for multi-channel SPDT relay output processing\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e*\u003cstrong\u003eA\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003ctd\u003eStyle code Revision A denoting standard board layout and terminal arrangement\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eMRO-234*A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eYokogawa\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eJapan\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.5 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e99 x 100 x 40 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e-20 deg C to 60 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e2.5 W nominal (coil energized state)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eContact Configuration\u003c\/td\u003e\n\u003ctd\u003eSPDT (Form C) electromechanical relay contacts\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal Coil Voltage\u003c\/td\u003e\n\u003ctd\u003e24 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Switching Voltage\u003c\/td\u003e\n\u003ctd\u003e250 VAC \/ 125 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Continuous Current\u003c\/td\u003e\n\u003ctd\u003e2 A per contact channel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGalvanic Isolation\u003c\/td\u003e\n\u003ctd\u003e2000 VAC between coil circuit and contact terminals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eChannel-to-Channel Isolation and Inductive Load Suppression\u003c\/h3\u003e\n\u003cp\u003eThe MRO-234*A relay board delivers complete galvanic isolation between sensitive internal DCS control electronics and high-voltage field loads. Each output channel utilizes dedicated optocouplers and mechanical relay armatures to prevent inductive voltage spikes, electrical fast transients (EFT), and ground loops from propagating back to the main system backplane. Built-in flyback diodes across the 24 VDC coil circuits dissipate counter-electromotive force (counter-EMF), stabilizing DC power rails during rapid contact switching cycles.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: What is the recommended contact protection when switching highly inductive DC loads with the MRO-234*A?\u003c\/p\u003e\n\u003cp\u003eA: Connect a free-wheeling flyback diode in parallel with inductive DC loads (such as solenoid valves or contactor coils) to suppress voltage transients and prevent contact erosion or arc-welding.\u003c\/p\u003e\n\u003cp\u003eQ: Does the MRO-234*A module support hot-swapping under live power conditions?\u003c\/p\u003e\n\u003cp\u003eA: Removal or insertion of the module should only occur after de-energizing field power to the relay contacts to prevent accidental switching states or terminal arcing during contact mating.\u003c\/p\u003e\n\u003cp\u003eQ: What is the physical breakdown voltage limit between channels?\u003c\/p\u003e\n\u003cp\u003eA: The internal barrier provides continuous dielectric isolation up to 2000 VAC for 1 minute between control logic inputs and field contact outputs.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhysical Mounting:\u003c\/strong\u003e Secure the module onto DIN rail or enclosure mounting plates using the integrated retention clips. Maintain at least 50 mm clearance above and below the module for adequate thermal convection.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWiring and Strain Relief:\u003c\/strong\u003e Use AWG 14 to AWG 22 stranded copper wire for field contact connections. Ensure terminal block screws are torqued to 0.5 N-m to prevent high-resistance contact points.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCable Separation:\u003c\/strong\u003e Route 24 VDC coil supply lines and high-voltage AC load cables through separate wire ducts to prevent crosstalk and capacitive noise coupling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGrounding:\u003c\/strong\u003e Bond the panel DIN rail or mounting chassis directly to the main functional earth (FE) bus bar using a low-impedance grounding strap.\u003c\/li\u003e\n\u003c\/ol\u003e","brand":"Yokogawa","offers":[{"title":"Default Title","offer_id":53280430227765,"sku":"MRO-234*A","price":66.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0973\/7630\/5461\/files\/MRO-234A.png?v=1786672295","url":"https:\/\/www.5gplc.com\/products\/yokogawa-mro-234-a-spdt-relay-output-module","provider":"High Five PLC Solution Limited","version":"1.0","type":"link"}