Delta BUB0705H 75x30mm 5V 0.50A 4-Wire PWM High-Static-Pressure Turbo Fan

Delta Electronics (Taiwan) · BUB Series · 75x75x30mm · 5V DC 0.50A · In stock

The Delta BUB0705H is a 75x75x30mm high-static-pressure turbo fan from Delta Electronics BUB series, designed for restricted-airflow cooling inside 1U rackmount servers, network switches, industrial PCs and high-density embedded enclosures. Operating on 5V DC at 0.50A, the BUB0705H ships with the standard 4-wire interface (V+ / GND / tach / PWM) and is footprint-compatible with the widely deployed 75x30 server-cooling slot used across telecom, datacom and OEM embedded platforms. The "turbo" designation in the BUB series refers to a high-static-pressure impeller profile, not a high-RPM consumer fan: the impeller keeps pushing air through dense heatsink fins, multi-device stacks and dust-filter media where a standard sleeve or ball-bearing fan would stall.

KOEED supplies Delta BUB series fans alongside spare parts from Allen-Bradley, Siemens, Mitsubishi, Omron, Fanuc, Schneider, Yaskawa, Panasonic and KEYENCE, so the cooling layer can be quoted on the same BOM as the PLC, HMI or servo hardware it is protecting. For obsolete and EOL Delta fan part numbers, see our real-time stock list or send the part label to our RFQ inbox.

1. Key Technical Specifications / Overview

The BUB0705H is built in Delta's Taiwan facility on the same platform as the rest of the BUB high-static-pressure family. Below is the engineering ledger used for replacement quoting. Values are read from the Delta datasheet; the 5V/0.50A rating is the canonical DC input and the 4-wire interface is the standard server PWM control pinout.

2. Application Scenarios / Where It Fits

The BUB0705H is engineered for confined, high-back-pressure enclosures where generic 75mm fans would lose airflow. Typical installations include:

• 1U rackmount servers and blade-server sleds — the 30mm depth lets it sit on a CPU or chipset heatsink with very little clearance above the board.
• Network switches, routers and high-port-count Ethernet gear — matched to the 75x30 server-cooling slot used on Siemens RUGGEDCOM and similar industrial networking platforms.
• Industrial PCs and edge gateways — installed in Allen-Bradley and Schneider edge-controller chassis where ambient temperature is regulated but the internal heatsink is dense.
• GPU and AI accelerator cooling modules — the 4-wire PWM allows the host BMC or controller to ramp the fan profile with workload, similar to Fanuc CNC spindle and servo drive layouts.
• Vision inspection enclosures and KEYENCE controller bays — KEYENCE CV-5000 and XG-8000 vision systems often spec a 75x30 fan in the head or controller bay; a high-static-pressure fan like the BUB0705H is required when filters are fitted.
• Servo amplifier and drive enclosures — backplane cooling on Yaskawa Sigma-7, Mitsubishi MR-J4 and MELSEC iQ-R panels, where the fan lives behind a foam filter.
• HMI and operator panel back-housing — replacement for aging Omron NS / NB and Panasonic GT-series panel internal fans.
• Custom embedded boxes and PoE switch stacks — wherever the airflow path is forced through a heat-sink tower rather than free-air, the BUB impeller keeps cfm up.

For plant-wide maintenance planning, see KOEED's AI Diagnostic Tool to confirm a BUB0705H is a pin-compatible replacement for a 75x30 server fan in a specific Allen-Bradley, Siemens, Mitsubishi, Omron, Fanuc, Schneider, Yaskawa, Panasonic or KEYENCE platform.

3. Integration & Wiring Notes

The 4-wire interface follows the industry-standard Intel/Delta server PWM pinout, so the BUB0705H can be wired directly into a standard 4-pin fan header on most embedded SBCs, server motherboards and PLC backplanes. The standard pinout is:

Power: the 5V rail should be sized to handle 0.50A continuous per fan plus inrush margin (recommend a 5V/1A fused supply per BUB0705H). If the host runs at 12V, use a buck-converter step-down to 5V before the fan header — do not bridge a 12V rail directly to the BUB0705H. For PLC backplane integration on Allen-Bradley or Omron CPUs, isolate the 5V fan supply from logic ground if the host uses a single-ended 24V common; the BUB's GND and host logic GND should be tied at one point only.

PWM control: drive the blue wire from a 5V-tolerant GPIO or a dedicated fan-control IC. Frequency is 25 kHz nominal; 0% duty stops the rotor, 100% is full rated speed. The tach output is open-collector and must be pulled up to the host logic level (3.3V or 5V) — 10 kohm is a typical pull-up. If you are swapping an older 3-wire Delta fan on a Panasonic FP-series backplane, leave the PWM pin floating; the BUB0705H will simply run at full speed in that case.

4. Installation & Commissioning Tips

• Airflow direction. Confirm the arrow on the fan frame matches the intended intake/exhaust orientation before powering up. Reversing a high-static-pressure fan in a tightly sealed enclosure can cause thermal runaway, particularly in Fanuc spindle and Yaskawa servo drive bays.
• Mounting flatness. The 75x30 frame should sit on a flat, rigid surface with all four corner grommets compressed evenly. Bowed mounting on a 1U server lid is a common cause of premature bearing wear.
• Filter maintenance. If a dust filter is fitted, clean or replace it on a defined interval. The BUB impeller will keep pushing air as the filter loads, but the host will see rising intake temperature and may trigger a fan-RPM alarm driven by the tach line.
• Clearance above the rotor. Keep at least 3 mm of free space above and below the rotor to prevent impeller contact in vibration. The BUB0705H's 30 mm depth is shallow by design, so this is usually not a problem in 1U and embedded enclosures.
• First-power commissioning. On first power, run the fan at 100% PWM duty for 30 seconds to verify the tach signal is present and stable, then hand off to the host's PID controller. For PLC-driven systems, log the tach frequency and compare against Delta's nominal rpm to confirm the fan is healthy.
• EMI consideration. The PWM edge is fast (25 kHz). Route the 4-wire harness away from analog signal cables, especially around KEYENCE vision and Siemens analog input modules, or add a small ferrite on the harness.
• Replacement interval. Ball-bearing Delta fans are typically rated for 50,000-70,000 hours at 40°C. For 24/7 cabinets in hot ambient (55°C+), plan a preventive swap at 5 years rather than running to failure.

5. Procurement, Warranty & Lead Time

KOEED stocks Delta BUB series cooling fans as part of our industrial-automation spare-parts portfolio. Each BUB0705H ships as a genuine Delta Electronics part from our China Sourcing Company network, with visual inspection, tach verification, and a documented chain of custody. Stock status is published on our real-time records page so you can confirm availability before requesting a quote.

Lead time. In-stock units typically ship within 1-3 business days from our Hong Kong / Shenzhen warehouses. For larger quantities (50+ units), or for matched Delta BUB series companions (BUB0512H, BUB0912H, BUB0712H and other 75x30 / 40x40 / 50x50 variants), confirm with Moritta@KOEED.COM — the response is normally within 24 hours on business days.

Warranty. Delta BUB0705H units are covered by a 12-month limited warranty against manufacturing defect under normal operating conditions. Warranty claims are handled by emailing the serial / lot sticker photo to Moritta@KOEED.COM along with the original KOEED invoice number.

BOM quotation. Most customers source the BUB0705H alongside a control-system BOM. If you have an Allen-Bradley ControlLogix chassis, a Siemens SIMATIC S7-1500 panel, a Mitsubishi iQ-R rack, an Omron NJ/NX controller, a Fanuc CNC retrofit, a Schneider Modicon M580 island, a Yaskawa MP controller, a Panasonic FP7 PLC, or a KEYENCE vision system — send the full part list in one email and we will quote the lot.

To open a quote, you can either fill in our Request-for-Quote form or email Moritta@KOEED.COM directly with the BUB0705H part number, quantity, and ship-to country. Engineers who need to size the air-flow / pressure trade-off before placing the order can use our free PLC Analog Calculator and Modbus CRC Calculator tools, or the AI Diagnostic Tool for a 24/7 chat-based answer on legacy Delta fan replacements.

Have a question before you commit? Reach the KOEED team at Moritta@KOEED.COM or use the contact form — we answer on business days within 24 hours, and the AI Diagnostic Tool is available 24/7 for urgent troubleshooting.