Charging Relay

How does a split charge relay work

A split charge relay is a device that splits the power of a single battery charging circuit into two paths. One path is an auxiliary load (such as an auxillary heater) while the other path — or branch– usually goes to two charge pumps in parallel so that one can supply current for boosting, and the second provide regulated current for charging batteries. A buss bar and/or wire connects to either terminal (+/-) of each to connect them together at one point, mostly for external wiring purposes but sometimes when only one could be charged simultaneously it served both as well because serial action limits recharge time due to lackadaisical generator output.


How to fit a split charge relay kit

You’ll see the circuits and connections on any of those kits, but basically you wire the solenoids for each side to a positive source (battery) and a negative source then do something called ‘splitting’ so that when you activate one motor by making a circuit to its terminal, it closes contacts which in turn activates the other motor. Typically this is done by using 2 switches in series- meaning when actuator 1 moves (Closes its connection), so does actuator 2. Which ever one of these is fitted will depend on what your installation involves as we’re all different.

How to test a split charge relay

Test a split-charge relay by connecting the battery charger to both “in” wires, one split apart from the other. If the battery will not charge then this is likely an issue with either the charging system or alternator. Connecting only one wire should have no impact on charging and will confirm that it’s an issue with your wiring setup.
Formula for figuring out how many volts of power you need in order to perform a specific function:
U = P × I  P = V ÷ I  I = U / P  V = U × P The formula you use depends on what voltage your toy requires v, how much amperage (A) it needs

How to wire a split charge relay

There are four pins on a charger relay. The two outside-most pins are where the output is located, and will each power one battery in your system. The two inside-most pins connect to the input – which should be plugging into your 12v source like an automobile’s cigarette lighter or a generator for example. The two outside-most wires of the input should go to the corresponding wires on the battery being charged so that both batteries charge at the same time and in balance with one another once you have hooked up both positive and negative terminals of your input wire to your desired 12v source.

What does a split charge relay do

A split charge relay is a specific type of relay that’s designed for use with 12 Volt DC applications. Common uses include charging batteries and supplying onboard power to electronics in boats, motorcycles, and other vehicles. The primary functions of a split charge relay are as follows: The first function is to isolate the battery from the vehicle or equipment whenever they’re not being powered by the system for extended periods of time. This guarantees that there will be no discharge issues when they finally need powering up again. Secondly, it splits the charging current between two sources in order to avoid overcharging one source while undercharging another. Lastly, it measures both input voltage levels so that if input voltage drops below optimum level (at which point splitting stops).

What size split charge relay do i need

The size of the split charge relay that you need is determined by the voltage at which your charger outputs, and also your battery banks. The desired function of a split-charge relay is to prevent overcharging one battery bank by charging another. It does this in two different ways. If your batteries are always charged to the same voltage, then it will isolate a single cell within the bank from being charged so that you can monitor its state without risk of overcharging because you have switched off all cells in this bank with an isolation switch during charging or use. If your batteries are never connected together but connected individually to power sources via their own chargers (such as solar panels).

SaleBestseller No. 1
Blue Sea Systems SI-ACR Automatc Charging Relay - 12/24V DC / 120A (7610)
  • Protects sensitive electronics by temporary isolation of house loads from engine circuit during engine cranking
  • 12/24 volt auto ranging voltage input
  • Hermetically sealed contacts/vaporproof
  • Ignition protectedâsafe for installation aboard gasoline powered boats
  • Supports high-output alternators up to 120 Amperes
Bestseller No. 2
MaySpare 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charging Relay Dual Smart Battery Isolator
  • 12V, 140A, 13.3V cut-in voltage, 12.8V cut-out voltage,; Package Include All the Bits and Pieces Needed for a Complete Installation
  • Working Voltage: Having Voltage Sensitive Chip,Rely Cuts in at 13.3 Volts and Cuts out at 12.8 Volts to Ensuring Primary Battery is Always Ready for Vehicle to Run.
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SaleBestseller No. 4
AMRM-7611 * Blue Sea BatteryLink Automatic Charging Relay - 12V/24V DC 120A
  • 120 Amp continuous rating. 12/24V DC auto ranging voltage input
  • Senses charging on two battery banks. Side and bottom knockouts for cable connections
  • Clip-on cover insulates terminal connections. 7∕8" (22 mm) stud length to accept multiple cable terminals
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  • Largest battery bank cannot exceed Group 27
Bestseller No. 5
Voltage Sensitive Relay - Automatic Charging Relay
  • Automatically combines two batteries when charging and isolates the two batteris when not charging.
  • Built-in LED indication (ON when VSR engages)
  • Available in both Surface and Panel Mount options
  • Optional Storage Mode allows zero power consumption when engine is off
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Bestseller No. 6
Bestseller No. 7
Dual Battery Isolator Kit 12 Volt 140 Amp Voltage Sensitive Relay Complete VSR Double Battery Automatic Charger
  • This item can install to most of vehicle,for example Truck, SUV, RV, ATV, UTV, Boat and so on.
  • Function: Cause your accessories to run from a separate battery while the engine is not working on your vehicle, and at the mean time holding your main battery charged and your vehicle always ready to work.
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Bestseller No. 8
Acouto Voltage Sensitive Relay 12V 125A VSR Double Battery Automatic Charging Relay Dual Smart Battery Isolator
  • 12V VSR---- A voltage sensitive relay (VSR) is the best way to ensure you can always get your dual-battery vehicle started. No voltage drops comparing to battery isolator diodes (0.6V). Continuous Current Rating: 125A. Intermittent Current Rating: 140A
  • Dual Battery Isolator---- Automatically combines two batteries when charging and isolates the two batteries when not charging. Once your main starter battery is sufficiently charged, the voltage sensitive relay will begin charging the second battery too
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Bestseller No. 9
Dual Battery Isolator Kit - 12 Volt 140 Amp Voltage Sensitive Relay - Complete VSR Double Battery Automatic Charger - Fits Trucks, SUV, ATV, UTV Boats and more - Safe, Water and Vibration Resistant
  • 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. This dual battery isolator kit features 12 Volt 140 Amp Voltage Sensitive Relay Isolator and includes all the bits and pieces needed for a complete installation.
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Bestseller No. 10
Gloaso 125 Amps Dual Battery Isolator VSR for 12V dc Car Boat RV Trucks Digital Voltage Sensitive Relay Automatic Charging Relay Water-Resistant
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  • 【Universal for dc 12v car, boat, rv, trucks etc.】Protects start batteries from becoming flattened by domestic loads
  • 【Great For Dual-Battery Vehicle】A max. 140 amps voltage sensitive relay (VSR) ensure you can always get your dual-battery vehicle started. Once your main starter battery charged completely , it will beginn to charge the second one
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  • 【Easy to Install, Surface or panel mount optional. 】No voltage drops comparing to battery isolator diodes (0.6V). Combine / Open Voltage: DC 13.3V / 12.8V