{"product_id":"blue-sea-7718-bss-ml-12v-500a-remote-battery-switch","title":"Blue Sea Systems 7718-BSS ML-Series 12V 500A Battery Switch","description":"\u003cp class=\"nvn-hero\"\u003eThe Blue Sea Systems 7718-BSS is a heavy-duty 12V 500-amp remote battery switch from the ML-Series. It ships with an SPDT ON-ON Contura remote switch and silver alloy contacts, so you can disconnect or combine battery banks right from the helm on a serious dual-battery boat.\u003c\/p\u003e\n\n\u003cdiv class=\"nvn-description\"\u003e\n\u003cp\u003eThe Blue Sea Systems 7718-BSS is a heavy-duty 12-volt remote battery switch from the ML-Series, rated for 500 amps continuous. It's built to make and break big DC loads from a distance, so you can kill power to the whole boat, or combine two banks, without ever crawling back to the battery box. It ships with an SPDT ON-ON Contura remote control switch and runs silver alloy contacts inside. That's the short version. Here's what it actually means on your boat.\u003c\/p\u003e\n\u003cp\u003eML stands for magnetic latching. Once the solenoid throws, it holds its position on its own, without drawing coil current to stay there. So you're not bleeding amps out of your house bank just to keep the switch closed. You flip the Contura switch at the helm, the solenoid latches, and it stays put until you tell it otherwise. For anyone running a boat that sits for weeks between trips, that's a real advantage over a switch that has to stay energized.\u003c\/p\u003e\n\u003cp\u003eThe 500-amp rating is continuous, and this switch will handle real engine-start and windlass loads on top of that. But that current has to get there. Run heavy cable to it, 4\/0 is typical on a 500-amp circuit, and torque the terminal lugs to spec. Loose lugs are the number one failure we see on any high-amp connection. They heat up, they corrode, and eventually they let go. Snug them down properly at install, then check them again at the start of every season.\u003c\/p\u003e\n\u003cp\u003eProtect the circuit, too. Put a suitably rated fuse or breaker close to the positive battery post, within about 7 inches of the source, so the cable is protected before it ever reaches the switch. The 7718-BSS switches the load. It doesn't protect it. That part is on you and your fuse, and it's not a corner to cut on a 500-amp system.\u003c\/p\u003e\n\u003cp\u003eSo where does it shine? Dual-bank setups on trawlers, cruisers, and sportfishers where you want a clean remote disconnect plus the option to combine banks for a jump-start or a heavy draw. Wire up the ON-ON Contura switch and you can cross-connect two battery banks or isolate them, right from the dash. No more reaching for a big manual selector buried in a locker. Pair the 7718-BSS with a Blue Sea automatic charging relay if you want automatic charging between banks with a manual override in the same system. It's a common combination on well-rigged boats, and the two are designed to talk to each other natively.\u003c\/p\u003e\n\u003cp\u003eA couple of honest notes before you buy. The black housing runs warm under sustained high load, so give it some air and keep it out of the hottest corner of the engine bay if you have the room. And it isn't a sealed unit. Mount it in a dry, protected spot, up out of the bilge. Moisture sitting on the coil terminals will corrode them over a season and rob you of reliability right when you're leaning on it. On a metal boat, run the remote switch leads in shielded cable to keep electrical noise off the signal so the switch doesn't false-trigger.\u003c\/p\u003e\n\u003cp\u003eThe silver alloy contacts are a big part of why this holds up. They resist welding under the heavy inrush you get from starting engines and spinning up a windlass far better than plain copper would. They'll still pit over years of hard high-amp cycling, that's just physics, but this is the contact set you want for the job. For a serious dual-battery boat that needs remote switching you can actually trust, the 7718-BSS is a solid pick. Wire it right, fuse it close to the post, keep it dry, and it'll run quietly for years.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul class=\"nvn-features\"\u003e\n  \u003cli\u003e500 amp continuous rating handles engine-start, windlass, and thruster loads on a 12V DC system\u003c\/li\u003e\n  \u003cli\u003eMagnetic latching ML-Series design holds position with no continuous coil draw, so it won't drain your bank\u003c\/li\u003e\n  \u003cli\u003eIncludes SPDT ON-ON Contura remote control switch for helm-side cross-connect or battery isolation\u003c\/li\u003e\n  \u003cli\u003eSilver alloy contacts resist welding under high-amp inrush better than plain copper\u003c\/li\u003e\n  \u003cli\u003eRemote operation lets you disconnect or combine banks without reaching the battery box\u003c\/li\u003e\n  \u003cli\u003eBlack housing and heavy-duty terminal studs built for the marine environment\u003c\/li\u003e\n  \u003cli\u003ePairs natively with a Blue Sea automatic charging relay for automatic charging with manual override\u003c\/li\u003e\n  \u003cli\u003eSized for 4\/0 cable on full-current 500-amp circuits\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv class=\"nvn-trust\"\u003e\n  \u003ch2\u003eWhy Buy from NVN Marine\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eAuthorized Blue Sea Systems reseller, full manufacturer warranty\u003c\/li\u003e\n    \u003cli\u003eNMEA member and ABYC certified, advice from real boat techs\u003c\/li\u003e\n    \u003cli\u003eSame-day shipping before 3 PM ET on in-stock items\u003c\/li\u003e\n    \u003cli\u003eNY headquarters and Fort Lauderdale flagship retail store\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"nvn-faq\"\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat does the Blue Sea 7718-BSS actually do?\u003c\/summary\u003e\n    \u003cp\u003eIt's a 12V, 500-amp remote battery switch from the ML-Series. It lets you make or break a heavy DC circuit, or combine two battery banks, from a switch at the helm instead of a manual selector at the battery box.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDoes it come with the remote switch?\u003c\/summary\u003e\n    \u003cp\u003eYes. It ships with an SPDT ON-ON Contura remote control switch. You mount that switch where you want the control, usually at the helm, and wire it back to the solenoid.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat size cable do I need for 500 amps?\u003c\/summary\u003e\n    \u003cp\u003eOn a full-current 500-amp circuit, 4\/0 cable is typical. Whatever you run, torque the terminal lugs to spec. Loose, undersized lugs are the most common failure point on any high-amp connection.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDoes the 7718-BSS need a fuse?\u003c\/summary\u003e\n    \u003cp\u003eYes. This switches the load, it doesn't protect it. Put a suitably rated fuse or breaker within about 7 inches of the positive battery post so the cable is protected before it reaches the switch.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eCan I mount it in the bilge?\u003c\/summary\u003e\n    \u003cp\u003eNo. It isn't a sealed unit. Mount it in a dry, protected spot up out of the bilge. Moisture on the coil terminals will corrode them over a season and hurt reliability.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat does the ON-ON Contura switch let me do?\u003c\/summary\u003e\n    \u003cp\u003eThe SPDT ON-ON switch gives you two active positions, so you can cross-connect two battery banks or isolate them from the dash. That makes it handy as a combiner for a jump-start or a heavy draw.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWill it drain my battery while it's switched on?\u003c\/summary\u003e\n    \u003cp\u003eNo. ML stands for magnetic latching. Once the solenoid latches it holds position without continuous coil current, so it isn't pulling amps out of your bank just to stay closed.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eCan I pair it with an automatic charging relay?\u003c\/summary\u003e\n    \u003cp\u003eYes. It works with a Blue Sea automatic charging relay so you get automatic charging between banks plus a manual override in one system. The two are designed to work together natively.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhy silver alloy contacts?\u003c\/summary\u003e\n    \u003cp\u003eSilver alloy resists welding under the big inrush from starting engines and running a windlass better than plain copper. They'll still pit over years of hard cycling, but they hold up well for high-amp switching.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"nvn-specs\"\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eTitle\u003c\/th\u003e\n\u003ctd\u003eBlue Sea Systems 7718-BSS ML-Series 12V 500A Battery Switch\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eBlue Sea Systems\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eManufacturer Part Number\u003c\/th\u003e\n\u003ctd\u003e7718-BSS\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eUPC\u003c\/th\u003e\n\u003ctd\u003e632085077181\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSeries\u003c\/th\u003e\n\u003ctd\u003eML-Series\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eProduct Type\u003c\/th\u003e\n\u003ctd\u003eSolenoid \/ Remote Battery Switch\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eVoltage\u003c\/th\u003e\n\u003ctd\u003e12 Volt DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eContinuous Amperage\u003c\/th\u003e\n\u003ctd\u003e500 Amps\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eHousing Color\u003c\/th\u003e\n\u003ctd\u003eBlack\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eRemote Control Switch\u003c\/th\u003e\n\u003ctd\u003eSPDT Remote Control Contura Switch (included)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSwitch Actuator Type\u003c\/th\u003e\n\u003ctd\u003eON-ON\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eContact Material\u003c\/th\u003e\n\u003ctd\u003eSilver Alloy\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n    \"@context\": \"https:\/\/schema.org\",\n    \"@type\": \"FAQPage\",\n    \"mainEntity\": [\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What does the Blue Sea 7718-BSS actually do?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It's a 12V, 500-amp remote battery switch from the ML-Series. It lets you make or break a heavy DC circuit, or combine two battery banks, from a switch at the helm instead of a manual selector at the battery box.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Does it come with the remote switch?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Yes. It ships with an SPDT ON-ON Contura remote control switch. You mount that switch where you want the control, usually at the helm, and wire it back to the solenoid.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What size cable do I need for 500 amps?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"On a full-current 500-amp circuit, 4\/0 cable is typical. Whatever you run, torque the terminal lugs to spec. Loose, undersized lugs are the most common failure point on any high-amp connection.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Does the 7718-BSS need a fuse?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Yes. This switches the load, it doesn't protect it. Put a suitably rated fuse or breaker within about 7 inches of the positive battery post so the cable is protected before it reaches the switch.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Can I mount it in the bilge?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"No. It isn't a sealed unit. Mount it in a dry, protected spot up out of the bilge. Moisture on the coil terminals will corrode them over a season and hurt reliability.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What does the ON-ON Contura switch let me do?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"The SPDT ON-ON switch gives you two active positions, so you can cross-connect two battery banks or isolate them from the dash. That makes it handy as a combiner for a jump-start or a heavy draw.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Will it drain my battery while it's switched on?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"No. ML stands for magnetic latching. Once the solenoid latches it holds position without continuous coil current, so it isn't pulling amps out of your bank just to stay closed.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Can I pair it with an automatic charging relay?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Yes. It works with a Blue Sea automatic charging relay so you get automatic charging between banks plus a manual override in one system. The two are designed to work together natively.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Why silver alloy contacts?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Silver alloy resists welding under the big inrush from starting engines and running a windlass better than plain copper. They'll still pit over years of hard cycling, but they hold up well for high-amp switching.\"\n            }\n        }\n    ]\n}\n\u003c\/script\u003e\n","brand":"Blue Sea Systems","offers":[{"title":"Default Title","offer_id":45005635944541,"sku":"2007970","price":184.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0299\/7266\/0317\/files\/ImageServerAPI_1f46fdc4-1570-4942-9ec5-814b4dd81e0e.jpg?v=1788766952","url":"https:\/\/nvnmarine.com\/products\/blue-sea-7718-bss-ml-12v-500a-remote-battery-switch","provider":"NVN Marine","version":"1.0","type":"link"}