Product Datasheet M-750 BATTERY SELECTOR/MASTER DISCONNECT SWITCH Specifications Vaporproof, water-resistant, dustproof and corrosion resistant. Ignition protected: conforms to USCG safety standard Section 183.410. UL and CE certified. M-750 Body diameter 5.00(127.00mm),mounting flange diameter 6.00 (152.40mm), overall height 2.64 (67.31mm). Three 3/8 - 24 copper studs. Functions either with alternators or generators. M-753 with keys Make before break design permits operation through the Features and Benefits On positions with the engine running. 500A intermittent, 310A continuous, 6-36V DC. Web Resources Available with enhanced features such as alternator field disconnect circuit. Download technical resources at: Provides a sure and reliable battery disconnection, littelfuse.com/M-750 protecting against electrical fire, tampering or theft, and Ordering Information battery drain. For any vehicle using two batteries, such as boats, PILOT MODEL LOCK ALTERNATOR FIELD DISCONNECT emergency and rescue vehicles, trucks, RVs, buses, and CIRCUIT utility trucks. M-750 OB M-752 M-753 OB M-754 Flange for easy flush Heavy spring ensures 3/8 - 24 copper All-weather hardware: Large knob for easy grip... mounting. Can also rock-solid electrical contact studs are solidly heavy copper studs and even when wearing gloves. mount through a panel. and provides strong detent machined to the brass nuts for maximum action to the switch. contact plates and current capacity. cannot come apart. 500 Amp Capacity Max Starting Power Water-Resistant Solid copper contact Corrosion-Proof Delivers maximum starting Impact-Resistant High-performance synthetic plates. Easily handles Stainless steel power: allows either or both Rugged polyester thermo- rubber o-ring keeps out amperages as high as screws securely hold batteries to be used. Can be plastic case and knob. Stands water, contaminants and 500A intermittent. Largest the plate against the switched between batteries even up to impact, maintains its vapors. Many battery amp capacity for the dollar o-ring, and keep the when the engine is running. water-resistant integrity. switches have no o-ring of any battery switch. switch watertight. Datasheet Replaces Hotfeed Number D-598 1 of 2 littelfuse.com 2020 Littelfuse Commercial Vehicle Products Rev: 081820Product Datasheet HM-750 BATTERY SELECTOR/MASTER DISCONNECT SWITCH Typical Wiring Diagrams for M-750 & M-751 2 Batteries, 1 Switch, 1 Engine, 1 Alternator 2 Batteries, 1 Switch, 1 Engine, 1 Alternator, with Battery Isolator SW 2 1 + + SW BAT 2 BAT 1 ALT + + BAT 2 BAT 1 ISO 1 2 L L ALT COM COM ALT 2 Batteries, 1 Switch, 1 Engine, 1 Alternator 2 Batteries, 1 Switch, 1 Engine, 1 Alternator SW 2 1 + + BAT 2 BAT 1 + + SW SW BAT 2 BAT 1 2 1 2 1 L2 L1 L2 ALT 2 L1 ALT 1 COM COM COM Key to the diagrams: BAT1 = Battery 1 and common COM = Common L1 = Starter No.1 & load BAT2 = Battery 2 and common SW = Switch L2 = Starter No.2 & load ISO = Battery isolator L = Starter & load ALT = Alternator Mounting CL M-750 series switches can be mounted flush or from behind, through a circular hole. When mounted flush, the switch covers over any holes previously made. When mounted from behind, No. 563 self-adhesive plastic sticker is available, which is identical to the ring-shaped sticker already on the switch. Surface Mounting Through Panel Mounting B2 CL A2 Drill four holes on a 5.500 Housing & knob clearance hole diameter circle (139.7mm). Hole 3.312 diameter (84.12mm). Drill size 0.218 (5.53mm) diameter four holes on a 4.395 diameter will accept No.10 screws. circle (116.63mm). Hole size 0.201 (5.10mm) diameter, 0.5 (12.70mm) A1 = 1.944 (49.38mm) deep for 1/4 -20 bolts. A2 = 3.888 (97.78mm) CL = Center line B1 = 1.553 (39.46mm) B2 = 3.107 (78.92mm) CL = Center line B1 A1 Visit Littelfuse.com for the most up-to-date product information. Littelfuse products are designed for specific applications and should not be used for any purpose (including, without limitation, automotive applications) not expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse product documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse product documentation. 2 of 2 littelfuse.com 2020 Littelfuse Commercial Vehicle Products Rev: 081820