{"id":4261,"date":"2025-10-21T17:04:37","date_gmt":"2025-10-21T17:04:37","guid":{"rendered":"https:\/\/1clickrepair.in\/ESS\/?post_type=product&#038;p=4261"},"modified":"2026-10-25T14:04:17","modified_gmt":"2026-10-25T14:04:17","slug":"r3-54b-panel-mount-fuse-holders-and-fuse-blocks","status":"publish","type":"product","link":"https:\/\/essfuse.com\/it\/prodotto\/r3-54b-panel-mount-fuse-holders-and-fuse-blocks\/","title":{"rendered":"5x20mm Panel Mount Fuse Holders &#038; Fuse Blocks | Industrial Grade Fuse Base"},"content":{"rendered":"<p><img decoding=\"async\" class=\"lazy aligncenter\" src=\"https:\/\/v7-upload.digoodcms.com\/website_193\/2025-07-17\/54b.png?imageMogr2\/format\/webp\" alt=\"R3 (54B) panel fuse holder image\" \/><\/p>\n<p><strong>Panel mount fuse holders<\/strong> and fuse blocks for 5x20mm cartridge fuses are standard panel-installed overcurrent protection components for low-voltage electrical systems. This 5x20mm panel fuse block adopts high-performance PBT insulating base paired with 0.5mm phosphor bronze conductive terminals, delivering reliable insulation performance, stable contact resistance and durable arc resistance for both AC and DC circuits. Its threaded panel mount structure and flame retardant housing make it widely applied in industrial control cabinets, switching power supplies, household appliances and front-panel instrumentation.<\/p>\n<h2>Core Product Features<\/h2>\n<ul>\n<li>Compatible with standard 5\u00d720mm glass and ceramic cartridge fuses, covering mainstream low-voltage protection specifications<\/li>\n<li>Dual rating: 6.3A at 250V AC; 10A at 125V DC, adapts to different low-voltage AC and DC scenarios<\/li>\n<li>PBT engineering plastic housing, UL94 V0 flame retardant grade, excellent heat resistance and electrical insulation<\/li>\n<li>0.5mm thick phosphor bronze terminals, high elasticity, stable clamping force, contact resistance below 5m\u03a9<\/li>\n<li>3000V AC power frequency withstand voltage, insulation resistance above 100M\u03a9, high operational safety<\/li>\n<li>50A breaking capacity, effectively interrupts fault current to protect downstream electrical components<\/li>\n<li>Threaded panel mount design, standard cutout size, tool-free front-panel fuse replacement<\/li>\n<li>RoHS compliant, meets global electronics safety and environmental protection requirements<\/li>\n<\/ul>\n<p>Compared with PCB mount fuse clips, this panel type model provides more flexible installation positions and easier daily maintenance. Its PBT housing offers superior thermal stability and chemical resistance, making it a standard protection solution for low-voltage control circuits and bench-top power supply units.<\/p>\n<h2>Full Technical Specifications<\/h2>\n<table style=\"border-collapse: collapse; width: 100%; border: 1px solid #000;\">\n<tbody>\n<tr>\n<th style=\"border: 1px solid #000; padding: 8px 12px; text-align: left; background: #f5f5f5;\">Specification Item<\/th>\n<th style=\"border: 1px solid #000; padding: 8px 12px; text-align: left; background: #f5f5f5;\">Parameter Value<\/th>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Model<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">R3-54B<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Compatible Fuse<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">5 \u00d7 20mm glass \/ ceramic cartridge fuse<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Rated Current &amp; Voltage (AC)<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">6.3A @ 250V AC<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Rated Current &amp; Voltage (DC)<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">10A @ 125V DC<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Breaking Capacity<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">50A<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Power Frequency Withstand Voltage<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">3000V AC<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Housing Material<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">PBT, UL94 V0 flame retardant<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Terminal Material<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">0.5mm thick phosphor bronze<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Contact Resistance<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">\uff1c 5 m\u03a9<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Insulation Resistance<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">\uff1e 100 M\u03a9<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Mounting Method<\/td>\n<td style=\"border: 1px solid #000; padding: 8px 12px;\">Panel mount, threaded nut fixing<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Selection &amp; Application Guidance<\/h2>\n<p>When selecting 5x20mm panel mount fuse holders and fuse blocks, first confirm the fuse size, system voltage type (AC\/DC) and operating current. The rated current is 6.3A for 250V AC circuits and 10A for 125V DC circuits, which should be selected according to the actual circuit type. Choose a 5x20mm fuse with appropriate current rating based on actual load, and reserve a 1.25\u20131.5 times safety margin to avoid overheating under continuous operation. For equipment requiring front-panel fuse replacement, panel mount models are preferred for convenient maintenance without opening the enclosure. For flame retardant and high insulation scenarios, PBT housing with UL94 V0 grade is recommended to ensure operational safety. Verify that the panel cutout matches the standard mounting size to ensure firm installation and stable contact performance.<\/p>\n<h2>Typical Application Scenarios<\/h2>\n<ul>\n<li>Industrial control panels and small automation equipment circuits<\/li>\n<li>Switching power supplies, adapters and power distribution units<\/li>\n<li>Test instruments and laboratory power supply circuits<\/li>\n<li>Household appliances and small electrical equipment<\/li>\n<li>Communication equipment and network terminal power protection<\/li>\n<li>LED lighting drivers and low-voltage power modules<\/li>\n<li>Medical equipment auxiliary circuits and control systems<\/li>\n<\/ul>\n<h2>Installation &amp; Maintenance Instructions<\/h2>\n<p>1. Select a 5x20mm cartridge fuse with matching current and voltage rating per circuit protection requirements.<\/p>\n<p>2. Drill a standard mounting hole on the equipment panel, insert the fuse holder from the front, and tighten the fixing nut from the back to ensure firm installation.<\/p>\n<p>3. Tighten circuit wires to the rear terminals and apply proper insulation treatment to prevent short-circuit hazards.<\/p>\n<p>4. Insert the fuse fully into the holder and tighten the end cap to ensure reliable contact and insulation performance.<\/p>\n<p>5. Do not operate beyond the rated voltage and current range to prevent insulation breakdown and safety risks.<\/p>\n<p>6. Disconnect power completely before fuse replacement to avoid electric shock and short-circuit damage.<\/p>\n<p>7. Inspect terminals and fuses periodically for looseness, oxidation or overheating signs, and replace components promptly if abnormalities are found.<\/p>\n<p><a href=\"https:\/\/essfuse.com\/wp-content\/uploads\/2025\/10\/R3-54B-5x20mm-Panel-Mount-Fuse-Holder.pdf\">R3-54B-5x20mm-Panel-Mount-Fuse-Holder<\/a><\/p>\n<h2>Frequently Asked Questions<\/h2>\n<p><strong>Q1: What fuse size do these panel mount fuse holders support?<\/strong><\/p>\n<p>A1: They are compatible with all standard 5\u00d720mm glass and ceramic cartridge fuses, the most widely used small-size specification for low-voltage equipment and control circuit protection.<\/p>\n<p><strong>Q2: What are the rated current and voltage?<\/strong><\/p>\n<p>A2: It supports dual ratings: 6.3A at 250V AC and 10A at 125V DC, covering most low-voltage AC and DC electrical equipment protection scenarios.<\/p>\n<p><strong>Q3: What material is the housing made of?<\/strong><\/p>\n<p>A3: The housing is made of PBT engineering plastic with UL94 V0 flame retardant grade, featuring excellent heat resistance, mechanical strength and electrical insulation performance.<\/p>\n<p><strong>Q4: What is the withstand voltage and insulation resistance?<\/strong><\/p>\n<p>A4: It supports 3000V AC power frequency withstand voltage, with insulation resistance above 100M\u03a9, providing high insulation strength and operational safety for low-voltage circuits.<\/p>\n<p><strong>Q5: What material are the terminals made of?<\/strong><\/p>\n<p>A5: The terminals are made of 0.5mm thick phosphor bronze, with high elasticity, contact resistance below 5m\u03a9, and stable clamping force after long-term use and multiple fuse replacements.<\/p>\n<p><strong>Q6: What mounting method does it use?<\/strong><\/p>\n<p>A6: It adopts panel mount design with threaded nut fixing, which can be directly installed on equipment front panels and control cabinet surfaces, with firm installation and convenient daily maintenance.<\/p>\n<p><strong>Q7: What are the main application fields?<\/strong><\/p>\n<p>A7: Widely used in industrial control equipment, switching power supplies, test instruments, household appliances, communication equipment and various low-voltage AC\/DC circuit overcurrent protection.<\/p>","protected":false},"excerpt":{"rendered":"<p>Industrial grade 5x20mm panel mount fuse holders and fuse blocks with PBT UL94 V0 flame retardant housing and 0.5mm phosphor bronze terminals, rated 6.3A 250V AC \/ 10A 125V DC, 3000V power frequency withstand voltage, designed for industrial control, home appliances and instrumentation circuit overcurrent protection.<\/p>","protected":false},"featured_media":4037,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"product_brand":[],"product_cat":[155],"product_tag":[],"class_list":["post-4261","product","type-product","status-publish","has-post-thumbnail","product_cat-panel-fuse-holder","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product\/4261","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/comments?post=4261"}],"version-history":[{"count":2,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product\/4261\/revisions"}],"predecessor-version":[{"id":15293,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product\/4261\/revisions\/15293"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/media\/4037"}],"wp:attachment":[{"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/media?parent=4261"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product_brand?post=4261"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product_cat?post=4261"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/essfuse.com\/it\/wp-json\/wp\/v2\/product_tag?post=4261"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}