MEAN WELL RD-85A is an enclosed dual-output AC/DC switching power supply with two separately specified DC rails: CH1 provides 5VDC at 8A and CH2 provides 12VDC at 4A. Its rated combined output is 88W. The two rails are not a selectable single output. Use each rail within its stated current range, observe any loading conditions in the datasheet, and keep combined loading within the rated total output. The metal enclosure measures 159 x 97 x 38mm and uses free-air convection cooling.Technical details below were checked against the MEAN WELL English series datasheet. Confirm final wiring, protection coordination, enclosure design, cooling, and derating against the datasheet before system integration.Features Two DC output rails - CH1 is rated for 5VDC at 8A; CH2 is rated for 12VDC at 4A. Combined output limit - Keep each rail within its specified current range and total loading at or below 88W; follow the series datasheet loading requirements. CH1 voltage adjustment - The CH1 adjustment range is 4.75-5.5V. AC/DC input - Accepts 88-264VAC or 125-373VDC at 47-63Hz according to the English series datasheet. Enclosed terminal design - Uses a metal enclosure measuring 159 x 97 x 38mm with screw terminals for installed equipment. Free-air convection cooling - Uses fanless cooling; validate enclosure airflow and derating for the finished system. Protection functions - Includes short-circuit, overload, and over-voltage protection. Ripple and noise - CH1 is specified at 80mVp-p maximum and CH2 at 120mVp-p maximum under the stated test conditions. Warranty - MEAN WELL lists a 3-year warranty for this series. Specifications Product MEAN WELL RD-85A switching power supply Series RD-85 Output configuration Two independently specified DC output rails CH1 rated output 5VDC, 8A CH1 current range 0-10A CH1 voltage adjustment 4.75-5.5V CH1 ripple and noise 80mVp-p maximum CH2 rated output 12VDC, 4A CH2 current range 0-5A CH2 ripple and noise 120mVp-p maximum Rated combined output 88W Typical efficiency 78% Input voltage range 88-264VAC or 125-373VDC Input frequency 47-63Hz Cooling Free-air convection Protection Short circuit, overload, and over voltage Operating ambient -25 to 70C; follow the datasheet derating curve Dimensions 159 x 97 x 38mm Warranty 3 years Reference DocumentsMEAN WELL RD-85 Series Datasheet - English PDFApplication Industrial control - Power compatible mixed-voltage control electronics after checking rail loading, wiring, and thermal margin. Automation equipment - Use within a documented system that accounts for rail loading, protection coordination, and enclosure conditions. Embedded electronics - Supply compatible circuits that require the specified 5V and 12V rails. Test and measurement fixtures - Integrate where the complete installation is designed within the voltage, current, and derating limits. Packing List Item Quantity MEAN WELL RD-85A switching power supply x1 FAQ.faq-accordion details{border-bottom:1px solid #e6eef8;padding:14px 0}.faq-accordion summary{cursor:pointer;font-size:16px;font-weight:700;color:#1f2933}.faq-accordion p{margin:12px 0 0;color:#4b5563;line-height:1.65} Does the RD-85A have two outputs?Yes. It has two separately specified rails: CH1 is 5VDC and CH2 is 12VDC. They are not a single selectable output. What current is available on each rail?CH1 is rated for 8A with a stated range of 0-10A. CH2 is rated for 4A with a stated range of 0-5A. Can both rails be used at the same time?Yes, when each rail remains within its specified current range and combined loading stays within the 88W rating. Follow the datasheet loading requirements. Which output is adjustable?CH1 has an adjustment range of 4.75-5.5V. Does it use a cooling fan?No. It uses free-air convection, so confirm enclosure airflow and derating before installation. What is included?The packing list includes one MEAN WELL RD-85A switching power supply.