{"product_id":"cnc-ac-1-pole-mcb-100a-circuit-breaker","title":"AC 1 Pole MCB 100A | Reliable Overload Protection","description":"\u003cdiv style=\"font-family:Segoe UI,Roboto,Arial,sans-serif;font-size:15px;line-height:1.7;color:#1a1a1a;\"\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eCNC 1 Pole 100A MCB — Heavy-Load Single-Pole Circuit Breaker\u003c\/h2\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003eThe CNC YCB9-125 is a high-ampere single-pole MCB rated at 100A — fitting into the gap between standard household MCBs (which top out around 63A) and bulky MCCBs. It gives you 100A protection in a compact 36mm (2-module) DIN-rail package that fits any standard Pakistani DB box.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003eUnlike standard 6kA MCBs, this breaker is rated at \u003cstrong\u003e10 kA breaking capacity\u003c\/strong\u003e — meaning it can safely interrupt fault currents up to 10,000 amperes. That higher rating is necessary at the 100A level because short-circuit fault currents scale with supply capacity, and installations drawing 100A are usually closer to larger transformers where fault levels are higher.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003eTypical use in Pakistan: \u003cstrong\u003emain incoming breaker for large single-phase residential or commercial premises\u003c\/strong\u003e, generator output protection on 15–20 kVA single-phase gensets, and solar inverter AC output protection where the inverter output exceeds the 63A capability of a standard MCB. CNC Electric is a trusted MCB brand in Pakistan with a \u003cstrong\u003e5-year replacement warranty\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eSpecifications\u003c\/h2\u003e\n\u003ctable style=\"width:100%;border-collapse:collapse;margin:16px 0 24px 0;font-size:14px;\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"border:1px solid #d0d0d0;padding:10px 12px;text-align:left;background:#f0f0f0;font-weight:700;color:#111;\"\u003eSpecification\u003c\/th\u003e\n\u003cth style=\"border:1px solid #d0d0d0;padding:10px 12px;text-align:left;background:#f0f0f0;font-weight:700;color:#111;\"\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eProduct Type\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eMCB — Heavy-Ampere Single Pole Miniature Circuit Breaker\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eModel\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eYCB9-125\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003ePoles\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e1P (Single Pole — disconnects live wire only)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eRated Current\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e100A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eRated Voltage\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e230V AC, 50Hz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eBreaking Capacity\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e\n\u003cstrong\u003e10kA at 230V AC\u003c\/strong\u003e (higher than standard 6kA MCBs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eTrip Curve\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eC-curve (trips at 5-10× rated current)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eStandard\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eIEC 60898-1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eMounting\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e35mm DIN rail\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eModule Width\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e2 modules (36mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eTerminal Capacity\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eUp to 50mm² cable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eRequired Cable Size\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e25mm² copper for 100A continuous\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eMechanical Life\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e20,000 operations\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eElectrical Life\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e10,000 operations\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eWarranty\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e5-year replacement warranty\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eWhen to Use a 100A MCB Instead of an MCCB\u003c\/h2\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003eAt 100A, you sit at the boundary between the MCB world (up to 125A) and the \u003ca href=\"\/collections\/ac-mccb-breakers\" style=\"color:#d42027;\"\u003eMCCB world\u003c\/a\u003e (100A–1600A). The choice between them depends on four factors:\u003c\/p\u003e\n\u003ctable style=\"width:100%;border-collapse:collapse;margin:16px 0 24px 0;font-size:14px;\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth style=\"border:1px solid #d0d0d0;padding:10px 12px;text-align:left;background:#f0f0f0;font-weight:700;color:#111;\"\u003eFactor\u003c\/th\u003e\n\u003cth style=\"border:1px solid #d0d0d0;padding:10px 12px;text-align:left;background:#f0f0f0;font-weight:700;color:#111;\"\u003e100A MCB (this product)\u003c\/th\u003e\n\u003cth style=\"border:1px solid #d0d0d0;padding:10px 12px;text-align:left;background:#f0f0f0;font-weight:700;color:#111;\"\u003e100A MCCB\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eBreaking capacity\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e10 kA\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e15–50 kA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eTrip settings\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eFixed (C-curve)\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eAdjustable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003ePhysical size\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003e2 DIN modules (36mm)\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eLarge panel-mount (100–150mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f9f9f9;\"\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003ePrice\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eRs.1,200\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eRs.5,500–9,000\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eBest for\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eResidential main incomer, small commercial premises\u003c\/td\u003e\n\u003ctd style=\"border:1px solid #d0d0d0;padding:10px 12px;\"\u003eIndustrial panels, high fault-level installations\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eChoose this 100A MCB if:\u003c\/strong\u003e your prospective short-circuit current is below 10 kA (typical for residential and light commercial premises), you want a compact DIN-rail breaker, and you need a fixed C-curve trip. \u003cstrong\u003eMove to a 100A \u003ca href=\"\/collections\/ac-mccb-breakers\" style=\"color:#d42027;\"\u003eMCCB\u003c\/a\u003e if:\u003c\/strong\u003e you are in an industrial environment close to a large transformer, or you need adjustable trip settings for motor coordination.\u003c\/p\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eWhere to Use the 100A Single-Pole MCB\u003c\/h2\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eMain incoming breaker for a large single-phase home\u003c\/strong\u003e — a house with 4+ air conditioners, electric geyser, EV charger, and large inverter easily draws over 63A. The 100A MCB sits at the top of the DB, with branch \u003ca href=\"\/products\/cnc-1-pole-mcb-ac-breaker-ycb7-63a\" style=\"color:#d42027;\"\u003e1 Pole MCBs\u003c\/a\u003e feeding the individual circuits. Pair it with a \u003ca href=\"\/pages\/voltage-protector-finder\" style=\"color:#d42027;\"\u003evoltage protector\u003c\/a\u003e and \u003ca href=\"\/collections\/spd\" style=\"color:#d42027;\"\u003eSPD\u003c\/a\u003e on the outgoing side.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eSingle-phase generator output protection\u003c\/strong\u003e — 15–20 kVA single-phase gensets produce roughly 65–87A continuous output. A 100A MCB on the generator's output panel protects the feeder cable and isolates the gen-set for maintenance without needing to move to an MCCB.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eSolar inverter AC output\u003c\/strong\u003e — hybrid and off-grid solar inverters rated 15–22 kW single-phase produce roughly 65–96A AC output. The 100A MCB is the standard AC-side protection element on the inverter feeder, positioned between the inverter and the house DB.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eShop or small commercial main breaker\u003c\/strong\u003e — retail outlets, clinics, and small restaurants with high refrigeration and AC loads. Simpler and cheaper than an MCCB where the fault current is under 10 kA.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eLarge UPS output distribution\u003c\/strong\u003e — 10-20 kVA single-phase UPS systems feeding multiple downstream DB boards.\u003c\/p\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eImportant Wiring Notes\u003c\/h2\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eUse 25mm² copper cable minimum.\u003c\/strong\u003e 100A continuous current in a 16mm² cable overheats and eventually ignites insulation. The cable is the first thing to fail, not the breaker. For longer runs (over 15 metres) or high ambient temperature, go up to 35mm² cable to allow for voltage drop.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eTighten terminal screws to specification.\u003c\/strong\u003e At 100A, a loose termination generates heat, discolours insulation, and can fuse the terminal into the conductor. Use a torque screwdriver and tighten to 2.5–3 Nm (or whatever the terminal label specifies). Check tightness again after 3 months of service.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003eProvide panel ventilation.\u003c\/strong\u003e At 100A continuous, the breaker dissipates heat. A closed DB box in a Pakistani summer can exceed 55°C internally, derating the breaker by up to 20%. Either up-size to 125A or provide forced ventilation on installations running near full load.\u003c\/p\u003e\n\u003cp style=\"margin:0 0 14px 0;\"\u003e\u003cstrong\u003ePair with a 2 Pole or 4 Pole upstream.\u003c\/strong\u003e For full isolation of both live and neutral (required during maintenance), this 1 Pole breaker should be preceded by a 2 Pole or 4 Pole main isolator. Alternatively, install this 100A MCB on only the live conductor and use a separate 100A neutral link.\u003c\/p\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eRelated Products\u003c\/h2\u003e\n\u003cul style=\"margin:10px 0 16px 20px;padding:0;\"\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eBranch circuits (downstream) → \u003ca href=\"\/products\/cnc-1-pole-mcb-ac-breaker-ycb7-63a\" style=\"color:#d42027;\"\u003e1 Pole MCB 2A-63A (Rs.425)\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eMain incomer with neutral switching → \u003ca href=\"\/products\/cnc-2p-mcb-ac-circuit-breaker-500v-ycb7h-63\" style=\"color:#d42027;\"\u003e2 Pole MCB 10A-63A (Rs.850)\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eThree-phase main incomer → \u003ca href=\"\/products\/cnc-4p-ac-mcb-circuit-breaker-ycb7h-63\" style=\"color:#d42027;\"\u003e4 Pole MCB 20A-63A (Rs.1,900)\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eAbove 100A or industrial fault levels → \u003ca href=\"\/collections\/ac-mccb-breakers\" style=\"color:#d42027;\"\u003eMCCB breakers 100A-1250A\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eVoltage over\/under protection → \u003ca href=\"\/pages\/voltage-protector-finder\" style=\"color:#d42027;\"\u003eVA Voltage Protector\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eLightning \/ surge protection → \u003ca href=\"\/collections\/spd\" style=\"color:#d42027;\"\u003eSPD surge protectors\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eEarth leakage protection → \u003ca href=\"\/collections\/rccb\" style=\"color:#d42027;\"\u003eRCBO breakers\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eAutomatic WAPDA\/generator switching → \u003ca href=\"\/collections\/ats\" style=\"color:#d42027;\"\u003eATS Automatic Transfer Switches\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eManual WAPDA\/generator switching → \u003ca href=\"\/collections\/changeovers\" style=\"color:#d42027;\"\u003eChangeover switches\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eComplete DB setup → \u003ca href=\"\/collections\/db-boxes\" style=\"color:#d42027;\"\u003eDB boxes\u003c\/a\u003e + breakers\u003c\/li\u003e\n\u003cli style=\"margin:0 0 6px 0;\"\u003eRead our guide → \u003ca href=\"\/blogs\/guides\/types-of-circuit-breakers\" style=\"color:#d42027;\"\u003eTypes of Circuit Breakers in Pakistan\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"font-size:22px;font-weight:700;margin:32px 0 14px 0;color:#111;line-height:1.3;\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eWhat is a 100A MCB used for?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eA 100A MCB is used as the main incoming breaker for large single-phase residential or commercial installations where the total load exceeds 63A — the limit of a standard household MCB. Typical applications include main breaker for a large home with multiple ACs, output protection for 15-20 kVA single-phase generators, AC output of large solar inverters, and main breaker for small commercial premises like shops or clinics.\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eWhat cable size do I need for a 100A MCB?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eUse \u003cstrong\u003e25mm² copper cable\u003c\/strong\u003e as the minimum. For runs longer than 15 metres or in hot environments, step up to 35mm² to allow for voltage drop and cable derating. Never use aluminium cable directly on MCB terminals — if aluminium supply cable arrives, terminate via a bi-metallic lug to copper pigtail at the breaker.\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eWhy is the breaking capacity 10 kA instead of 6 kA?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eBreaking capacity has to match the prospective short-circuit current at the point of installation. Standard household circuits (branch level) have fault currents under 6 kA, so 6 kA MCBs are adequate. At the main incomer level drawing 100A, fault currents are typically 8–10 kA, so the 100A MCB is rated at 10 kA to safely interrupt those faults. If your main incomer is close to a large transformer where fault currents exceed 10 kA, move up to a 100A MCCB with 15–50 kA breaking capacity.\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eWhat is the 100A MCB price in Pakistan?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eThe CNC YCB9-125 1 Pole 100A MCB is available at Rs.1,200 at CNC Electric Pakistan. Competitor brands: Schneider iC60N 1P 100A typically costs Rs.4,500–6,000, and Chint NB1 1P 100A costs Rs.1,800–2,200. CNC offers equivalent IEC 60898-1 certified performance with 10 kA breaking capacity at a significantly lower price with a 5-year replacement warranty.\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eShould I use a 100A MCB or a 100A MCCB?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eUse the 100A MCB if your prospective fault current at the installation point is under 10 kA (typical for residential and light commercial premises). Use a \u003ca href=\"\/collections\/ac-mccb-breakers\" style=\"color:#d42027;\"\u003e100A MCCB\u003c\/a\u003e if you are in an industrial environment close to a large transformer (fault level above 10 kA), or if you need adjustable trip settings for motor coordination or selective tripping between main and sub-mains.\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eCan I use a 100A MCB on a three-phase supply?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eNo. This is a single-pole MCB for single-phase circuits (230V AC). For three-phase 400V applications requiring 100A protection, use an \u003ca href=\"\/collections\/ac-mccb-breakers\" style=\"color:#d42027;\"\u003eMCCB\u003c\/a\u003e rated 100A 3P or 4P, or combine three of these 1-pole MCBs linked mechanically (not recommended for safety reasons — go to the MCCB).\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eDoes the 100A MCB need a separate neutral switch?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eYes — since this is a single-pole breaker, the neutral is not switched. For full-isolation maintenance, install either a separate 100A isolator on the neutral wire, or pair this 1P MCB with a main 2 Pole MCB upstream. In most modern installations, you would use a true \u003ca href=\"\/products\/cnc-2p-mcb-ac-circuit-breaker-500v-ycb7h-63\" style=\"color:#d42027;\"\u003e2 Pole MCB\u003c\/a\u003e at the main incomer if the load is below 63A, and this 100A 1 Pole for heavier loads with a separate neutral isolator.\u003c\/p\u003e\n\u003ch3 style=\"font-size:17px;font-weight:700;margin:22px 0 8px 0;color:#111;\"\u003eHow much DB space does the 100A MCB occupy?\u003c\/h3\u003e\n\u003cp style=\"margin:0 0 18px 0;\"\u003eThe CNC YCB9-125 100A MCB is 36mm wide — two DIN-rail modules. That makes it the same width as a 2 Pole MCB, allowing easy substitution in existing DB layouts. Plan your DB capacity: a 12-way DB with this 100A main and 10 branch 1 Pole MCBs uses 2 modules for the main + 10 for branches = 12 total, fitting exactly.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"CNC Electric Pakistan","offers":[{"title":"100A","offer_id":42324151369794,"sku":"YCB9-125","price":1200.0,"currency_code":"PKR","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0605\/2059\/5522\/files\/1P_100A_MCB_AC_Circuit_Breaker.webp?v=1755853207","url":"https:\/\/www.cncelectric.pk\/products\/cnc-ac-1-pole-mcb-100a-circuit-breaker","provider":"CNC Electric Pakistan","version":"1.0","type":"link"}