Weidmüller WSI 6/LD Fuse Disconnect Terminal Block

The Weidmüller WSI 6/LD is a 6 mm² fuse-disconnect terminal block that combines a screw-clamp feed-through terminal with an integrated LD-series cartridge fuse holder in a single DIN-rail mounted component. Rated for 57 A conductor current and fuse ratings up to 25 A (dependent on the installed fuse type), the WSI 6/LD provides individual branch-circuit overcurrent protection at the point of termination — eliminating the need for a separate MCB or fused isolator for each instrument or control loop branch in Saudi DCS marshalling panels. The LD-series fuse holder accepts standard 5 × 20 mm glass fuses and RT18 (10 × 38 mm) type fuses covering 250 mA to 25 A, giving panel designers flexibility to match the fuse rating precisely to each branch-circuit load without over-specifying fuse size. The knife-disconnect function of the LD-series holder allows the fuse to be withdrawn for circuit isolation without any additional disconnecting tool, meeting IEC 60947-3 isolator requirements for maintenance access to individual branch circuits in live MCC and marshalling panels.

The WSI 6/LD is designed to replace the combination of a feed-through terminal, a separate fuse block, and a jumper bridge — reducing panel terminal strip length by typically 30–40% on Saudi marshalling sections that incorporate branch-circuit fusing. The 6 mm pitch and compatible DIN rail footprint allow the WSI 6/LD to be mixed within the same terminal strip as WDU 4 feed-through terminals and WDU 2.5 instrument terminals, providing a single-strip layout for power-in, fuse, and instrument-loop termination without the space penalty of separate fuse blocks. Weidmüller's fused terminal design includes a visual indicator flag that drops when the fuse blows, providing a clear fault indication without voltmeter access — a key maintenance feature in Saudi panel rooms where quick fault finding during production plant trips is critical.

The WSI 6/LD is widely used in ARAMCO DCS and ESD marshalling panels for 24 V DC transmitter loop power distribution, where individual field instrument loops must be individually fused to prevent a single instrument cable fault from collapsing the entire 24 V bus. In SABIC's Jubail petrochemical complex control room panels, WSI 6/LD fuse terminals are used to individually protect PLC analog output channels, where a field-short on a 4–20 mA output to a current-to-pneumatic converter must be isolated to the affected channel without affecting adjacent channels. The NEOM smart-city Building Management System (BMS) panel specification for the Sindalah Island marina and the NEOM Bay Airport terminal building requires individually fused 24 V DC sensor power distribution — a requirement directly met by the WSI 6/LD approach.

Razz Middle East stocks the WSI 6/LD fuse terminal in both the bare-terminal and complete-with-fuse kit options, along with the full range of 5×20 mm and RT18 fuse values from 250 mA to 25 A in GKN and Bussmann series. Our team provides fuse-discrimination studies for ARAMCO DCS marshalling panel fuse-scheme reviews, cross-references to Phoenix Contact FUK 2.5 and Siemens SIRIUS 8WH fuse terminal equivalents, and pre-assembled fused terminal strip services with Weidmüller M-series label markers. All WSI 6/LD supplies include Weidmüller factory test certificates, IEC 60947-3 declarations, and SASO customs clearance documents.