12V-48V DC Marine Battery Isolator Switch with 1000A Cranking Rating and ON-OFF Two-Position Rotary Battery Disconnect Switch

A battery master switch earns its place the day someone has to kill the power in a hurry. The MT068 answers that moment with a two-position rotary head that clicks into ON or OFF and stays there — no half-turned dial, no guessing which way is dead. Under the housing, a solid copper bridge carries 250A continuously and swallows 1000A for the few seconds an engine or bow thruster needs to crank.

What makes this part worth stocking is the voltage spread: DC 12V through 48V from a single SKU. A dinghy tender, a 24V workboat, a 36V golf car and a 48V electric outboard all take the same switch, so a distributor carries one box instead of four and the wrong-part return disappears from the counter.

• One dial, one unambiguous state — The head stops hard at each end, so a glance from the helm tells you whether the bank is live. Vibration from a planing hull will not walk the dial out of position.
• Copper where the heat is — A solid copper bridge runs lower resistance than plated steel, which means cooler studs and a contact face that still cleans up after years of cycling.
• A shell that holds its shape — ABS is moulded rather than soft-formed, so terminals stay square when heavy lugs are torqued down and the body does not creep in a hot engine bay.
• Salt, fuel and sun — The sealed joint keeps spray and dust off the contact set, which is what stops a switch from welding shut in a marine environment.

Sales sheets quote the big cranking number because it looks impressive. Wire to it and the switch will discolour and eventually weld. The table below is the order to think in.

1. Isolate and prove dead — Turn the dial to OFF, disconnect the negative lead first, then confirm zero volts at both studs before you touch anything else.
2. Size the cable for 250A — Work from the continuous rating and add margin. The 1000A figure sizes nothing — it only describes the start burst.
3. Mount to a rigid surface — Use a flat panel or bracket. A flexing surface lets the stud nuts loosen over the season.
4. Land the lugs — Bank positive on one stud, starter or distribution feed on the other. Closed ring lugs only, crimped with the matching die.
5. Torque, cycle, verify — Tighten both nuts fully by torque, cycle the dial once off load, then reconnect and check stud temperature after the first loaded run.

Model MT068, ON-OFF two-position rotary, ABS housing with copper current path, rated 250A continuous and 1000A cranking at DC 12V–48V. Minimum order 5 pieces, price quoted against quantity and packing. Standard production runs 30 days from deposit, T/T or Western Union with 30% down and the balance before shipment. Units ship in export cartons; pallet quantities and mixed containers can be quoted on request.

Send us your system voltage, cable cross-section and the number of banks you need to isolate, and we will confirm the right MT068 configuration and packing for your order.