150A ON-OFF Battery Isolator Switch DC 12-24V Marine Battery Disconnect Switch for Boat RV

Lay-up season and pre-season survey are when battery isolation actually gets examined. A surveyor wants to see that the master switch isolates everything downstream, that it is rated for the circuit, and that the terminals are sound. Owners want a switch that still turns freely after a winter in a cold locker.

MT034 is a 150 amp, two-position rotary isolator for 12 to 24 volt DC systems, sized for the typical cruiser, camper or utility vehicle board. One movement to ON, one to OFF, with hard stops at both ends so the position can be confirmed without opening anything up.

The body mounts on a flat flange, the conductor path is copper, and the studs accept standard ring lugs. Nothing about it needs maintenance beyond a torque check and a clean dial face.

1. Turn the switch to OFF before the boat or vehicle is left for the season.
2. Prove isolation with a meter at the distribution block, not just at the dial.
3. Disconnect the battery negative if the bank is being removed or left unattended.
4. Clean salt and dirt from the housing so the dial turns freely in spring.
5. Note the switch position and rating in the maintenance log for next season.

• Correct rating — 150A continuous is adequate for a standard domestic board and small engine circuit.
• Full isolation — ON-OFF design breaks the entire downstream feed, with no bypass link.
• Sound terminations — ring lugs crimped and torqued, no twisted wire or tape joints.
• Accessible mounting — the flange is reachable and the dial faces the operator.
• Voltage coverage — 12V and 24V systems both inside the rated window.

• Two-position rotary dial with a positive stop at ON and at OFF.
• Copper conductors inside the housing for a low-resistance current path.
• Moulded body with a flat fixing flange for panel or locker wall mounting.
• Large terminal studs that accept standard crimped ring lugs.
• Face legend readable at arm's length and identifiable by touch.

Mount the body where the dial can be reached with a hand and seen from the helm or entry point. Keep cable bends generous behind the panel, land battery positive on one stud and the distribution feed on the other, and tighten both nuts fully. Finally, operate the dial once with no load, then reconnect the battery and confirm the whole board goes dead at OFF.

• Minimum order — 5 pcs.
• Price — negotiable, quoted against quantity and packing requirements.
• Capacity — 50,000 pcs per month.
• Lead time — 30 days for standard production.
• Payment — T/T or Western Union; 30% deposit with the balance before shipment.
• Packing — neutral white box inside a brown carton; branded packing available with written trademark authorisation.