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Deka Battery Isolator - 120 Amp

Deka Battery Isolator - 120 Amp

Item # DW08771
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Our Price: $70.99
Battery Charger
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DW08771 - 6V,12V,24V,36V,48V,50V Deka Battery Isolators
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This 120-amp battery isolator enhances your alternator performance for efficient charging, maximum power, longer battery life, and safer operation. Protects main starting battery from auxiliary drain. Regulates current for multi-battery system. Call 800-298-8924 to order Deka battery charger part number DW08771 or order online at etrailer.com. Free expert support on all Deka products. Guaranteed Lowest Price and Fastest Shipping for Deka Battery Isolator - 120 Amp. Battery Charger reviews from real customers.
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  • Reviews (5)
  • Q & A (44)
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Deka Battery Charger - DW08771

  • Battery Isolators
  • Deka
  • 6V
  • 12V
  • 24V
  • 36V
  • 48V
  • 50V
  • Vehicle Battery to Auxiliary Battery

This 120-amp battery isolator enhances your alternator performance for efficient charging, maximum power, longer battery life, and safer operation. Protects main starting battery from auxiliary drain. Regulates current for multi-battery system.


Features:

  • Ideal for automotive, marine, and RV applications
  • Enhances your alternator performance for
    • Efficient charging
    • Maximum power
    • Longer battery life
    • Safer operation
  • Protects main starting battery from auxiliary drain
  • Regulates current for multi-battery system


Specs:

  • Application: alternators with amperage ratings below 120 amps
  • Capacity: 120 amps
  • Overall dimensions: 6-1/2" long x 4-1/2" wide x 3" tall excluding bolts
  • Quantity: 1
  • 1-Year limited warranty


Dimensions

Note: It is recommended that you purchase an isolator with an amperage rating above that of your alternator to prevent any damage to the isolator.


In a multi-battery system, the battery with the lower state of charge will drain power from the battery with the higher state of charge. This battery isolator protects your starting battery power so that no matter how weak your accessory battery becomes, the accessory battery will never drain power from the starting battery. This battery isolator also saves time by allowing simultaneous charging of both batteries. The amount of current flowing into each battery is determined by its state of charge, which guarantees that each battery will get fully charged, prolonging its life.



08771 Deka Battery Isolator - 120 Amperes




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Customer Reviews

Deka Battery Isolator - 120 Amp - DW08771

Average Customer Rating:  5.0 out of 5 stars   (5 Customer Reviews)

This 120-amp battery isolator enhances your alternator performance for efficient charging, maximum power, longer battery life, and safer operation. Protects main starting battery from auxiliary drain. Regulates current for multi-battery system.

- DW08771
by:

Ordered by phone with Gwen and Stacy's help and elected to pickup the battery isolator in Wentzville, Missouri. Price was great and it has a one-year warranty. Within an hour or two they emailed it was ready. Pickup was also quick and professional. Item is an exact replacement for the 25-year-old failed part in terms of form, fit and function. Installed without rewiring or drilling and is working great! This could not have been a better experience! 678468



- DW08771
by:

All I can say is that Etrailer ROCKS! Ordered on Tuesday and got it Thursday. The only thing better is if I could’ve picked it up myself! Thanks Etrailer for fantastic service! 614903



- DW08771
by:

Great selection and very reasonable prices, many with discounts, often cheaper than that big online site. Particularly impressed with customer service when I had a product issue, called me right away and offered replacement item immediately with free UPS return label. 592457



- DW08771
by:

So far it works fine. 524210



- DW08771
by:

Haven't installed it yet. Delivery was quick and the product was what I ordered. 510395


5
5

Ask the Experts about this Deka Battery Charger

  • How To Protect the 12 Volt Circuit On a 7-Way From a Generator
    It sounds like you are asking if you can use a battery isolator to protect the battery on your tow vehicle from the generator while powering items on your trailer. If that is the case then yes, the Deka Battery Isolator part # DW08771 will work for you. However, I doubt you will be drawing anywhere close to 120 amps so you would most likely save some money with the 95 amp version, part # DW08770.
    view full answer...
  • Is Circuit Breaker Needed When Wiring Deka Battery Isolator # DW08771
    When wiring up the Deka Battery Isolator # DW08771 the main/first battery will connect directly to position one on the isolator without the need for a circuit breaker. The second battery though should be attached to the second position on the isolator via a circuit breaker that is rated appropriately for the battery. The alternator will go to the A post on the isolator. I have attached a diagram that you might find helpful as well. You should not have to worry about the second battery...
    view full answer...
  • Using Deka Battery Isolator to Charge Battery Bank on Shuttle Bus
    The Deka Battery Isolator # DW08771 is what you'd need for what you are looking to do. I attached a wiring diagram that shows how it wires up but basically you'd just need to wire the battery 2 auxiliary you see in the picture as a battery bank wired in series like you are wanting. This adapter then would allow you to charge these batteries as needed without draining the vehicle battery.
    view full answer...
  • Deka Battery Isolator to Replace Eaton Sure Power 1202 Battery Isolator With Wiring Diagram
    The Deka Battery Isolator - 120 Amp # DW08771 will work with alternators with amperage ratings below 120 amps so it will work well with your 63-74 alternator with external regulator. You will simply connect it as the attached diagram shows. The extra post you asked about will not be used since you don't have a group 1 alternator, but that would be connected to a circuit breaker and eventually to the ignition switch.
    view full answer...
  • How to Wire a Two Battery Universal Isolator # DW08771 on 2002 Ford E450
    As long as your two marine batteries are wired parallel and are essentially one battery you will wire the Sure Power Two Battery Universal Isolator, # DW08771, that you referenced as follows: The A post will go to the alternator output. The number 1 post will go to the vehicle main battery positive post. And the number 2 post will go to the auxiliary battery through a circuit breaker to the positive battery post.
    view full answer...
  • How to Charge Up a Trailer Mounted Battery While Driving
    The 12 volt circuit on a 7-Way trailer connector is not adequate for charging up a trailer mounted battery. At best it can maintain the current charge in the battery assuming nothing is drawing power from it. Solar power takes a very long time to charge up a typical 12 volt car-type battery so it will need a little help to charge up the battery. Take a look at the DC to DC charger # 331-BCDC1225D. With this unit you can actually charge up the trailer battery while you drive. It has inputs...
    view full answer...
  • Way to Charge Trailer Battery that Provides More than Maintenance Charge
    The Tow Ready Isolation Solenoid part # TR118665 has an 80 amp rating which is pretty high. This would be more than enough for the 12 volt circuit of your 7-way feeding a battery on your trailer. Typically this circuit is rated at 40 amps or less. This method will provide a maintenance charge on your battery but would not charge a dead battery. Most likely it's not the alternator that would need to be increased to get more charge on your trailer's batteries. The limiting factor is going...
    view full answer...
  • How to Boost Charging Amps of Second Battery
    If you are looking to boost the charging for your second battery then you actually need a maintainer/charger because a battery isolator like part # DW08771 is designed to keep the second battery from draining the main battery. For your application I recommend using the Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D because it not only has an integrated isolator but it also features a multi-stage algorithm that detects and charges your second battery according to its needs. The...
    view full answer...
  • How to Charge Trailer From Secondary Battery with Isolator
    It sounds like you currently have an isolator like the Deka # DW08771 installed between your primary and secondary battery on the trailer. If this is the case, then running a 12V wire from the 7-Way connector to the secondary battery positive post should give you exactly what you are looking for. I have included a diagram that might help with the wiring for this setup.
    view full answer...
  • How Do Batteries Charge with Deka Battery Isolator DW08771
    If you intend to wire the two batteries together they should be the same type but if you want to add a second independent battery for the winch/lights/stereo it can be a different type and/or have a different amp-hour (Ah) rating. A separate system means no risk of depleting your vehicle's primary battery. You want to consider the power draw of each of the items and select a battery with a high enough Ah rating. The winch will draw much more power than the lights or stereo so that is...
    view full answer...
  • How to Wire Deka # DW08771 Battery Isolator
    I've found a wiring diagram for the # DW08771 Battery Isolator. Terminal 1 would connect to the positive battery terminal of the main battery. The original wire from the alternator to the main battery would be removed from the battery and installed on terminal 1. Terminal E would connect to the an ignition circuit that's hot only when the key is switched on via a 6 amp breaker. Terminal A would connect to the battery lead on the alternator and Terminal 2 would connect to the positive terminal...
    view full answer...
  • Isolator Relay Recommendation for a Allowing Switch Power Cable for Trailer Battery
    What you are going to want to install on the power cable that runs from your tow vehicle to the battery is the isolator part # TR118665. Connect the power cable on either end of the isolator and then run a separate power source to the middle pin of it with a switch installed on it like part # D16740. This will allow you to control the power of the circuit by flipping the switch.
    view full answer...
  • Will the Battery Isolator Voltage Result in the Battery Being Undercharged
    I contacted our technical representative at Deka and he stated it all depends on your alternator on your vehicle. If you have a remote sense alternator, the charge time will increase by 50%. Your battery will gain its full charge from your vehicles alternator. You wouldn't need to worry about your battery being undercharged. The remote sense alternator provides highly accurate voltage readings and optimizes your vehicle battery state-of-charge. This results in the improved efficiency...
    view full answer...
  • Wiring a Trailer Mounted Winch to a Trailer Battery and Vehicle Battery
    I have just what you will need. I have linked an FAQ article that explains the various ways to wire a winch. You will need the second half of the page titled Option 2: Wiring the Winch to a Separate, Trailer-Mounted Battery. I have also included a picture that shows how it would all go together. You will need a battery isolator, # TR118665, some wire like # 10-1-1 or # 12-1-1 sold in 1 foot increments, and a 40 amp circuit breaker # PK54540. You will wire it all up like in the picture. Please...
    view full answer...
  • Isolator Recommendation for 2014 Chevrolet Silverado Using 2nd Battery
    The highest rated isolator that we offer is one like the Deka Battery Isolator, # DW08771, which has a capacity of 120 amps. From the information that I was able to gather on a 2014 Chevrolet Silverado it has an alternator with an amp rating greater than 120. This isolator can be used with a higher amp rating alternator because an alternator typically will not be producing it's full amperage unless something were to require it like a dead vehicle battery. In this case, if the full amperage...
    view full answer...
  • Is a Battery Isolator or Diode Needed When Charging a Trailer Battery from a 2007 Ford F-150
    The 12V Power pin on your 2007 Ford F-150 (which you said is labeled as Trailer Battery Feed Hot with Key in Run Only) will provide a maintenance charge to the battery on your trailer. The only time that a battery isolator or a diode is needed is when the 12V Power would be running while the trailer is hooked up and without the tow vehicle on. Since your F-150 will only be sending power to the 12V pin you will not need an isolator or diode. If you were wanting your trailer to pull power...
    view full answer...
  • Wiring Diagram for Battery Isolator Use with Two 6 Volt Golf Cart Batteries
    The Deka Battery Isolator - 120 Amp # DW08771 will allow you to hook up to a 12V ignition battery as well as two 6V golf cart batteries connected in series. This is a great choice as long as your alternator amperage rating is below 120 amps. It is recommended that you purchase an isolator with an amperage rating above that of your alternator to prevent any damage to the isolator. I've attached a wiring diagram as you requested to assist, just where you see battery 2 auxiliary you will...
    view full answer...
  • Installing Battery Isolator 08771 in 2002 Ford Excursion
    I have a diagram attached that shows all of the intended connectors from the Deka Battery Isolator # DW08771 to your 2002 Ford Excursion. Terminal E would connect to the an ignition circuit that's hot only when the key is switched on via a 6 amp breaker. When talking to an install technician they advised me that a 2 type alternator is not important when your goal is to just wire in a auxiliary battery. As long as the circuits are not overloaded or the power is too much for the isolator....
    view full answer...
  • How Does DEKA Isolator part # DW08771 Attach to Two Batteries
    I attached a diagram that shows how the DEKA Isolator part # DW08771 that you referenced needs to get wired to a vehicle with two batteries. Basically the center isolator post gets the alternator connection and then position 1 goes to the battery that cranks the vehicle starter and position 2 goes to the auxiliary battery positive terminal. The fourth terminal of this would not get used. The fourth one is the one with the smaller diameter threads.
    view full answer...
  • Battery Isolator Recommendation for 2012 Toyota FJ Cruiser Running Second Battery
    Since the alternator of your 2012 Toyota FJ Cruiser is rated for 100 amps the Deka isolator part # DW08771 that you referenced would be exactly what you are looking for. I attached a wiring diagram for this isolator for you to check out as well.
    view full answer...
  • Wiring diagram for Battery Isolator
    For your battery isolator similar to # DW08771, you will have connection posts for each battery and for an alternator. The main battery will connect to position one and the alternator to the A post. The second battery will attach to the 2 via a circuit breaker that is rated appropriately for the battery. Output from the second battery positive post will then go to the items you want to power. I have included a picture that should help. If you do not have a group 1 alternator then the...
    view full answer...
  • How to Wire Up a Sure Power 120 Amp Two Battery Isolator
    Battery isolator # DW08771 will have connection posts for each battery and for an alternator. The main battery will connect to position one and the alternator to the A post. The second battery will attach to the 2 via a circuit breaker that is rated appropriately for the battery. Output from the second battery positive post will then go to the items you want to power. I have included a picture that should help. If you do not have a group 1 alternator then the E post will not be used....
    view full answer...
  • Is Deka Battery Isolator part # DW08771 Weatherproof
    The Deka Battery Isolator part # DW08771 is considered weather proof but I would not put it in a location that would allow it direct water access. So not on a boat trailer that would get submerged or directly out to get rained on. If you can avoid those things you'd be fine.
    view full answer...
  • Wiring Diagram for Deka # DW08771 Battery Isolator
    I've found a wiring diagram for the # DW08771 Battery Isolator. Terminal 1 would connect to the positive battery terminal of the main battery. The original wire from the alternator to the main battery would be removed from the battery and installed on terminal 1. Terminal E would connect to an ignition circuit that's hot only when the key is switched on via a 6 amp breaker. Terminal A would connect to the battery lead on the alternator and Terminal 2 would connect to the positive terminal...
    view full answer...
  • Installing the Deka Battery Isolator In Marine Application With Outboard Motor
    For your outboard motor on a boat applicaiton, when installing the Deka Battery Isolator - 120 Amp # DW08771 you can just connect the alternator terminal to the starting battery as you mentioned. This will still isolate a second battery in the format that you have stated. I've attached a diagram to help and it shows the dotted line from the alternator back to the positive terminal of the battery. This will allow the second battery to charge with ignition on, but will not allow second...
    view full answer...
  • Wiring a Trailer With Dual Batteries and Solar Charger
    Let's try and take this one at a time to make things easier; to start with the black wire from the 7-way plug (the 12V) should be run to the pair of 12V batteries you already have in the battery box. In terms of grounding they will be grounded through your Redarc In-Vehicle BCDC Battery Charger # 331-BCDC1225D. The LED lights each need to be grounded to the frame of your trailer; they will also be connected to the 12V batteries which would be connected to the charger. That covers...
    view full answer...
  • Recommended Battery Isolator for In-Bed Camper on 2006 Dodge Ram Pickup
    Thank you so much for all of the info! The Tow Ready Battery Isolation Solenoid # TR118665 does serve it's purpose but I do understand the need for something that is able to do a bit more. The best solution that we have to offer is the Redarc Smart Start Battery Isolator with Wiring Kit # 331-SBI12KIT because it allows you to install the isolator in-between the start and auxiliary batteries instead of having to install it between the alternator and batteries (it is recommended to...
    view full answer...

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Info for this part was:

Expert Research:
Michael H
Expert Research:
Jameson C
Expert Research:
Adam R
Written by:
Laura H
Updated by:
Sarah W
Updated by:
Mike S

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