Mean Well DBUF DIN Rail Buffer Module (20A/40A) Installation & Service Manual PDF (EN)

Installation Manual Type DBUF DIN rail Buffer Module DBUF20-24 Charging Voltage: 23-30VDC OUTPUT: 20A (max) DBUF40-24 Charging Voltage: 23-30VDC OUTPUT: 40A (max) Introduction The DBUF buffer module is a supplementary device for regulated DC 24V power supplies. The buffer module utilizes maintenance-free electrolytic capacitors to store energy, thus eliminates the need of periodic replacement as compared to costlier batteries which also have shorter functional life span. The DBUF comes with comprehensive protection features like over voltage, over current and short circuit protections. Buffer modules can be connected in parallel to increase the output ampacity or the hold-up time .

Like other Mean Well’s DIN series, they can be mounted on a TS35 Standard DIN rail. Installation 1 Always allow good ventilation clearances, 5mm left and right, 40mm above and 20mm below, around the unit in use to prevent it from overheating. 2 The appropriate mounting orientation for the unit is vertical, the TB1 terminals at the bottom. Mounting orientations other than that, such as upside down, horizontal, or table-top mounting, is not allowed. 7 The recommended torque setting for terminals is 10kgf-cm(9Lb-in). 8 Mounting Instruction: Mount as shown in figure only, with input terminals down, or else sufficient cooling will not be possible.

Admissible DIN rail TS35/7.5 or TS35/15 For rail fastening （3）Use copper wire only, and recommended wires are shown as below. AWG 18 16 14 12 10 Rated Current of 7A 10A 15A 20A 30A Equipment (Amp) Cross-section of 0.8 1.3 2.1 3.3 5.3 Lead(mm2 ) Note: 1. Current each wire carries should be de-rated to 80% of the current suggested above when using 5 or more wires connected to the unit. 2. The maximum allowable wire cross-sectional area for the terminal is 10 AWG/ 5.3 mm2 . Make sure that all strands of each stranded wire enter the terminal connection and the screw terminals are securely fixed to prevent poor contact.

If the power supply possesses multi-output terminals, please make sure each contact is connected to wires to prevent too much current stress on a single contact. AWG 18 16 14 12 10 Rated Current of Equipment (Amp) 7A 10A 15A 20A 30A Cross-section of Lead(mm2 ) 0.8 1.3 2.1 3.3 5.3 Note: 1. Current each wire carries should be de-rated to 80% of the current suggested above when using 5 or more wires connected to the unit. 2. The maximum allowable wire cross-sectional area for the terminal is 10 AWG/ 5.3 mm2 . Make sure that all strands of each stranded wire enter the terminal connection and the screw terminals are securely fixed to prevent poor contact.

If the power supply possesses multi-output terminals, please make sure each contact is connected to wires to prevent too much current stress on a single contact. （4）Use wires that can withstand temperatures of at least 80°C, such as UL1007. （5）Recommended wire strapping length is 5mm (0.197”). （6）Recommended screwdriver is 4mm, slotted type.

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Installation Manual a Tilt the unit slightly rearwards. b Fit the unit over top hat rail. c Slide it downward until it hits the stop. d Press against the bottom for locking. e Shake the unit slightly to check the locking action. 9 For other information about the products, please refer to www.meanwell.com for details. Typical Application Notes 1 2 3 4 "Click" 1. General wiring diagram 2. Signals supplied from an external voltage

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Installation Manual 3. Paralleling of buffer units Warning / Caution !! 1 Risk of electrical shock and energy hazard. All failure should be examined by a qualified technician. Please do not remove the case of the power supply by yourself! 2 Risk of electric arcs and electric shock (danger to life). Connecting both the primary and the secondary sides together is not allowed. 3 Risk of burn hazard. Do not touch the unit in operation and shortly after disconnection! 4 Risk of fire and short circuit. The openings should be protected from foreign objects or dripping liquids. 5 Only install the unit in a pollution degree 2 environment (Note.1).

6 Please do not install the unit in places with high moisture or near the water. 7 The maximum operating temperature is 75°C, please do not install the unit in places with high ambient temperature or near fire source. 8 Output current and output wattage must not exceed the rated value on its specification. 9 Disconnect system from supply voltage: Before commencing any installation, maintenance or modification work: Disconnect your system from supply voltage. Make sure that inadvertent connection in circuit will be impossible! 10 For continued protection against risk of fire, replace only with same type and rating of fuse.

Pour ne pas compromettre la protection contre les risquй d’incendie, remplacer par un fusible de mкme type et de memes caractйristiques nominales. Note.1: Pollution Degree 2 applies where there is only non-conductive pollution that might temporarily become conductive due to occasional condensation. Generally refer to dry, well-ventilated locations, such as control cabinets.

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Installation Manual Manufacturer MEAN WELL ENTERPRISES Co., LTD. No.28, Wuquan 3rd Rd., Wugu Dist., New Taipei City 24891, Taiwan Tel: +886-2-2299-6100 Web: www.meanwell.com Branch Office China MEAN WELL (GUANGZHOU) ENTERPRISES Co., LTD. No.11, Jingu South Road, Huadong Town, Huadu Distric, Guangzhou, Gungzhou, China Tel: +86-20-3773-7100 Web: www.meanwell.com.cn China SUZHOU MEAN WELL TECHNOLOGY Co., LTD. No.269 Changping Rd. , Huangdai Town, Xiangcheng District Suzhou, Jiangsu Province, China Post Code: 215152 Tel: +86-512-6508-8600 Web: www.meanwell.cc U.S.A. MEAN WELL USA, INC. 44030 Fremont Blvd., Fremont, CA 94538, U.S.A. Tel: +1-510-683-8886 Web:

www.meanwellusa.com Europe MEAN WELL EUROPE B.V. Langs de Werf 8, 1185XT Amstelveen, The Netherlands Tel: +31-20-758-6000 Web: www.meanwell.eu 2026.01.12

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