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MaySpare Voltage Sensitive Rela helps to reserve a fully charged battery at all time, avoid the dead battery and possibility of towing on the sea.
- This Kit provides all the necessary cables, accessories and the VSR that you need to install the secondary battery with the VSR
- The dual battery isolator kit enables your accessories to run from a separate battery while the engine is not running on your vehicle while keeping your main battery charged and your vehicle always ready to go and start when you want it to.
HOW DOES MaySpare SAMRT BATTERY ISOLATOR WORK
When the voltage of start battery is higher than cut-in volts, the smart battery isolator (SBI) keeps engaging, two batteries (start and house) are charged simultaneously. Unit Indictor (LED) is on.
When the batteries no longer have a charge from the alternator, and loads on the batteries begin to delete them. Unit Indicator (LED) is on.
When the voltage drops below cut-off volts for 5 seconds, the SBI senses it and disengages, separating both batteries. Unit Indicator (LED) is off.
When the vehicle is restartd, the start battery has reached the cut-in volts, the SBI engaged again. Unit Indicator (LED) is on.
Zero Voltage Drop
- This Dual Battery Isolator is the only unit designed with cutting edge programming to deliver optimum performance.
- When the voltage of the start battery drops the isolator kit disengages from charging the auxillary battery.
- This isolates the start battery and eliminates the possibility of draining it, ensuring that you always have enough charge to start your engine.
Weather Resistance
- This dual battery isolator is also built to withstand extreme weather environments, vibration and is water resistant.
- It is safe for use, even your vehicle needs in dusty, wet and unexpected extreme weather environments.
Dustproof
Outer firmly enclosed casing and a silicone sealed internal layer, protects YOUR isolator from dust, dirt, sand and any other substance that could cause damage to isolator.
Sale Service
- 100% OEM Match and Replacement
- The solenoid relay meets your expectations
Dale Weidinger
Reviewed in the United States on March 16, 2025
Quick and easy to follow instructions. It works flawlessly in my bass boat to keep the trolling battery charged while on the lake.
James Henderson
Reviewed in the United States on April 8, 2025
Bought two to replace the manual battery switches on my boat. After a while one stopped working. Had to unhook it, and hook it back up to get it working again, so I replaced with a different brand. Getting ready for a new season, and now the other is failing.Worked good...but only for a year or so.
Jerry
Reviewed in the United States on September 16, 2024
After receiving this item I determined that it would not work for my installation, therfore I have returned it to the supplier.
Rusty
Reviewed in Canada on August 4, 2024
I put it in my side by side with leaked power to ground some how. Was wired correctly. Always had to boster to start buggy ended up shorting out the new battary I bought and to late to return .
Michel R.
Reviewed in Canada on August 6, 2023
Works , good buy
Dean
Reviewed in Canada on July 8, 2023
Hooked it up on my boat to charge my trolling motor battery. Work great and charges fast.
Adam B.
Reviewed in Canada on August 11, 2022
I converted a Ford Transit Connect into a camper and used this isolator in it. Been over a year and still working great. Used wire from jumper cables to connect the main vehicle battery to 2 batteries in the back that I use to power the lights/fan/water pump and usb outlets. No issues with the main vehicle battery draining. Great value for the price.
TL Tooling Ltd
Reviewed in Canada on November 25, 2022
Missing some components
Delvin I.
Reviewed in the United States on January 4, 2022
It is compact and simple and works to keep both boat batteries charged without risk of draining starting battery
Cole O'Neil
Reviewed in Canada on July 27, 2021
Kills battery’s when there’s no constant charge
YOLI LEE
Reviewed in the United States on October 15, 2021
I've used this in my truck to hookup my second battery and have not had 1 issue with it. Works exactly as it should and never has given me an issue. I've used this with Solar on my truck as well and it worked flawlessly than as well. It's been 6 months since I installed it so I don't recall the instructions if they were any good. I see in 1 review that someone doesn't know what the yellow cable is for and I thought I'd clarify.Black = GroundYellow = *WHEN GROUNDED TO METAL* Will connect both batteries to each other regardless of voltage. ONLY WHEN GROUNDED. You can test it out and hear an audible "click" of the relay connecting the batteries together.Overall it's worked out perfectly, I would recommend for anyone looking to do a similar setup for cheap.
Michael Nikolai
Reviewed in Canada on January 27, 2021
Very easy to install. It works perfect for a dual battery set up. So far it's holding up great in -25C Temps. I have a bypass switch on order so I can use the yellow wire bypass the isolator if needed.Sure, you can go with a manual isolator however if you want an easy and automatic solution then this is it.
Dave
Reviewed in Canada on November 18, 2020
Great product for adding a second battery, easy to install and good value.
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