Ferraz Shawmut FD27GRB66V4T — 4A 660VDC High-Speed DC Fuse (1PCS)

Ferraz Shawmut (Mersen) · FD27 Series · gRB Class · In stock

The FD27GRB66V4T is a 4-ampere, 660-volt DC high-speed fuse from the Ferraz Shawmut / Mersen FD27 family, a recognized premium European protection device used as a string, combiner and battery-link fuse in solar PV combiner boxes, battery energy storage systems (BESS) and DC drive cabinets. The “gRB” utilization class marks it as a full-range, general-purpose fuse with high DC breaking capacity — well suited to the harsh inductive let-through of photovoltaic and traction circuits.

This listing ships 1 piece in protective packaging — ideal for field-service replacement of a single tripped fuse or for engineering bench evaluation. Bulk pricing is available for solar integrators and BESS OEMs through our BOM quotation desk.

Key Specifications

Datasheet Highlights

• 660 VDC rating — covers residential and small-commercial PV string voltages (600 V / 1000 V class systems) and typical BESS battery-link rails when used in pairs.
• gRB utilization class — general-purpose full-range protection (g) with verified DC breaking performance (R), engineered for semiconductor-rectifier and battery circuits where AC-only NH gG curves are insufficient.
• 4 A calibration — suits small PV string feeds, sub-array combiner outputs, auxiliary DC control supplies and small DC-drive input branches where sustained current stays well below the 4 A threshold.
• Low I²t let-through — limits peak fault energy reaching downstream PV isolators, contactors, and busbars, which is critical when protecting thin-film or back-contact modules sensitive to arc-flash damage.
• Drop-in fit for FD27 holders — shares the FD27 body with the wider FD27GRB66Vx series (different current ratings), simplifying spares stocking in solar and BESS panels.
• Indicating version — the “4T” suffix typically marks a top-indicator (striker) variant for remote blown-fuse signaling in automated combiner boxes.

For the full time-current curve, watts-loss data, and the certified DC test certificate, request the manufacturer datasheet from Moritta@KOEED.COM or read our fuse selection guide for engineering guidance on gRB vs gPV classes.

Typical Applications

• Solar PV combiner boxes — string-side protection for residential and C&I PV arrays feeding inverters from SMA, Sungrow, Huawei, ABB and similar DC-input stages.
• Battery energy storage (BESS) racks — per-string or per-module DC-link protection in 48 V / 120 V / 600 V battery cabinets and DC-coupled hybrid inverters.
• DC drive & soft-starter input — upstream of the rectifier on small DC drives, elevator drives, and traction auxiliaries where the DC bus sees sustained inrush.
• Traction and rail auxiliaries — field replacement on older DC-fed rail and metro auxiliaries where Ferraz / Mersen is the OEM-specified fuse brand.
• Field-service replacement — a single 1PCS pack is the standard SKU for engineers who need to swap a tripped fuse on a combiner or drive without opening a 10-pack.
• EV charging DC modules — auxiliary DC rails in DC fast-charging stations where a 4 A gRB class is required by the cabinet designer.

This listing complements our wider DC fuse collection and the cross-brand Ferraz / Mersen fuse lineup stocked at KOEED.

Related Modules & Cross-Reference

Engineer’s note: the FD27GRB66V4T shares the same 660 VDC rating philosophy as Mersen’s rebranded DC Protistor lineup. When migrating from legacy Ferraz stock to current Mersen catalog codes, confirm the indicator variant (top striker / center mount) and the bus-mount torque before substituting in production. KOEED is an independent multi-brand distributor covering nine major automation brands (Allen-Bradley, Siemens, Mitsubishi, Omron, Fanuc, Schneider, Yaskawa, Panasonic, KEYENCE) — not an authorized subsidiary of any of them.

Warranty & Authenticity

• Genuine Ferraz Shawmut / Mersen — sourced through the brand’s authorized channel network, not unbranded replicas; factory markings, date code and lot traceable on request.
• Pre-shipment inspection — resistance check, visual indicator check and packaging integrity verified before dispatch.
• Worldwide shipping — DHL / FedEx / UPS door-to-door, with export documentation and HS-code declarations handled by our China sourcing team.
• 24-hour quote turnaround — send a single-line part number or a full BOM and we will respond with availability and tiered pricing on the next business day.
• Bulk pricing for integrators — solar combiner box builders and BESS integrators receive tiered pricing on case quantities; MOQ and lead time confirmed per RFQ.
• Replacement guarantee — if a fuse is found DOA on receipt, we replace or refund on a verified claim within the standard return window.

All commercial terms — warranty period, return policy and lead time — are confirmed in writing with the formal quotation. See our shipping policy and return policy for details, or write to Moritta@KOEED.COM with your project requirements.