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OptiMate 5 Start/Stop Smart Battery Charger - AC to DC - 12V - 4 Amp

OptiMate 5 Start/Stop Smart Battery Charger - AC to DC - 12V - 4 Amp

Item # MA94JR
Our Price: $87.95
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Battery Charger
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Shipping Weight: 2 lbs
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Compact smart charger draws power from a wall outlet to automatically charge and maintain batteries on cars, trucks, SUVs, motorcycles, lawnmowers, ATVs, and personal watercraft. Saves sulfated batteries as low as 2V. Charges 12V lead-acid batteries. 1-800-496-5010 to order OptiMate battery charger part number MA94JR or order online at Free expert support on all OptiMate products. Great prices and Fastest Shipping for OptiMate 5 Start/Stop Smart Battery Charger - AC to DC - 12V - 4 Amp. Battery Charger reviews from real customers.
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OptiMate Battery Charger - MA94JR

  • ATV
  • Jet Ski
  • Lawn Mower
  • Motorcycle
  • Battery Charger
  • 12V
  • OptiMate
  • Wall Outlet to Vehicle Battery
  • Charges/Maintains
  • AC to DC
  • Smart Charge

Compact smart charger draws power from a wall outlet to automatically charge and maintain batteries on cars, trucks, SUVs, motorcycles, lawnmowers, ATVs, and personal watercraft. Saves sulfated batteries as low as 2V. Charges 12V lead-acid batteries.


  • AC-to-DC smart charger quickly charges and maintains a battery
    • Perfect for charging car, truck, SUV, motorcycle, lawnmower, ATV, tractor, truck, SUV, or boat
    • Ideal for eco-friendly cars with start-stop technology - safe for sensitive electronics
  • Multiple battery profiles let you charge a variety of lead-acid battery types
  • 6-Step charging algorithm automatically charges and maintains without overcharging
    • Analyzes battery condition to provide a customized charge
    • Built-in battery desulfator restores lost battery capacity
  • Battery clamps provide a quick, easy way to connect to your battery
  • Eyelets let you make a secure connection to your battery terminals
    • 15-amp fuse protects electronics from potential short circuits
    • Zip tie slits allow easy fastening to vehicle
    • SAE connector with weatherproof seal and cap keeps out dirt and water
  • Simple operation with LED lights that indicate charging status
  • Durable, weatherproof case includes wall mounts, 6' AC supply lead, and 6' charge lead with SAE connector


  • Application: 12V batteries from 15 to 192 amp-hours
  • Battery types supported: flooded, AGM, and gel
  • Maximum charging amperage: 4 amps
  • Cable lengths:
    • Battery clamps: 20"
    • Eyelets: 20"
    • AC power: 6'
    • Charging cable: 6'
  • Input voltage: 100 - 240 VAC (50 - 60 Hz)
  • Low voltage detection rating: 2 volt
  • Lowest operating temperature: -4 F (-20 C)
  • 3-Year limited warranty

TM221 OptiMate 5 Start/Stop 6-Step 12V 4A Sealed Battery Saving Charger and Maintainer

Replaces TM-221

Installation Details MA94JR Installation instructions

Video of OptiMate 5 Start/Stop Smart Battery Charger - AC to DC - 12V - 4 Amp

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for OptiMate Ampmatic Smart Battery Chargers Review

Hi there truck trailer and RV owners! Today, we're going to be taking a look at Optimates line of smart battery chargers for non-lithium, 12 volt systems. So here we have our four options for 12 volt system battery chargers. They do come in various amperage outputs, and as we go up in amperage, we do get a little bit extra testing with it's charge strategy. So while it's charging them, it'll actually test the batteries to adjust its strategy along the way to ensure that it's charging your batteries optimally, to get them up to a hundred percent and also ensure it's not charging them too fast, where it could potentially degrade the life cycle of the battery. And as we go up higher, you're going to have a little bit better protection with each. Down here on the bottom this one's mostly just a maintainer with an output of 0.8 amps, so it's mainly a maintainer.

If it's a smaller single battery, you could potentially charge it up with this one here. And this one does have the least amount of testing involved with it, it's just a four-step system that goes through a lot of your typical charging strategies to get it up charged, and then maintained. As we move up to the four amp charger, There's some additional testing that occurs with this one to ensure that we've got the best charge strategy for this battery. There's a six step process in this one, and we've got four amps of output here. And with four amps, that's going to be ideal for a single battery or even a two battery bank system, depending on the capacity that you've got available there.

And it will be able to charge us with real high capacities. It's just, it may take in a much longer time. We can move up to five amps. This one's only a little bit higher output, but this has a nine step charge process. So it does additional tests of the battery along the way during its charge process, to make sure that each step is going to have the best possible charge strategy.

And it's going to be the same here with the 10 amp, but with 10 amps available, we're going to be able to charge up larger battery banks. Maybe we've got four, six batteries in the bank. We should be able to get this charged up easily and in a reasonable amount of time with a 10 amp charger like this. So here today, we've got our fifth wheel in the background and we're going to be charging up the batteries on this. We're going to go ahead and show off the five amp charger on this because that's going to be a great charger for a single or dual battery setup like we've got here.

If we had more batteries in there, we might move up to the 10, but the five should be just fine. The 10 will reduce the amount of time to charge them. So if you're looking to get a charge quickly then the 10 might be a better option for you, but we're going to be showing off the five. Our four amp charger here is going to be great for a single battery setup. I've got a pop-up camper at home so something like this is a really good option, but with the extra steps on the five amp, it might be worth it to just do that little bit of upgrade here because it can help to extend the life of the battery. Just a little bit more by having the most appropriate charge strategy. It's probably not going to be a huge difference, but that could be maybe one more year of life you get out of the battery with using this one, versus some of the other ones. And down here with just one, just being a battery maintainer, this is really just for keeping your battery charged up while it's in storage and stuff like that. So that way it's not going to desulfate or have any issues, um, wearing out its capacity from sitting in storage for so long. And if you've got something small, like an ATV or something like that, that has a smaller battery. You could probably get that charged up pretty easily with this as well. So we've got our battery compartment on our fifth wheel trailer here. This is the one that was sitting right behind us. This is our battery box here. And if we just lift it up we can see inside that we've got two batteries. So this is the one battery bank of two batteries, and they're hooked together in parallel. And we can tell that because we can see the negative here is connected to the negative here. The black cable is just running from one to the other. Same with our positives. There's a cable, just connecting the two positives together. So since they're hooked together in parallel, that means that each one is a 12 volt battery. The voltage is going to maintain the same, still going to be 12 volts for our system here, but the capacity of each battery is going to add together. So we'll have twice the capacity When you're charging them you could hook one of your leads to the negative and one to the positive. It doesn't matter which battery, since they're hooked in parallel, if it was series, it would be a different story. You need to make sure in a series set up that you're hooking at the beginning for the negative of your series set-up and hookup with the positive at the end of the bank. But on parallel, it doesn't matter, you can just pick a negative, pick a positive or together in series they'll charge, but something like this, oftentimes on top of your battery box, you'll find it post just like this. And this is actually a jump or charge port here. If we wanted to hook up power supply to run our trailer, we can hook our power supply up here. Or if we wanted to charge the batteries, we could hook up right here because these posts are connected right down to our batteries. You'll receive two different types of cables with your battery charger. We've got just the regular clamp style here, and this is what we're going to use today just to show off. And this is great for just quickly charging up some batteries. If you're moving your charger around, maybe you use your charger to charge up, uh maybe your lawnmower at home. Uh maybe then you move over and you could charge up one of your vehicles, your bike. If you're just moving around a lot maybe your boat you're charging up and then your camper. So these are great for being able to quickly move your charger from one to the other. This one knows a more permanent type of cable, and this is really nice for a trailer like this. We could install this directly onto the batteries. And what that would do for us is provide us with a hookup here, So we could just plug our charger directly into this. That would just simplify the setup, because if you don't have any posts like this up top here, and your batteries are inside of a container, they're vented here to get rid of some of that gases. It's pretty necessary for batteries. So if you can't get inside easily, instead of taking these screws out and lifting up this cover to hook up your clamps to it, you can just permanently install this and leave this cable just kind of draping out the side here and then you just plug right in and we can get those charged up. And since this is going to be permanently mounted onto your trailer, the positives and negatives are going to be hooked up, which means that the other end of the cable here is live. So they put the fuse protection in there. So in the event that maybe your caps here all had fell in off, all fallen off, and then this touches some kind of ground, if it we're to short you don't have to worry about any damage caused to your wiring or any kind of fire or anything like that, starting with just open fuse. So it's cool that they've got protection in there for you for any accidents. And then if we look at the other end here on this particular cable, it comes with this little sleeve on it. And that works as a dust cap. So you can even install this on a trailer. Like my pop-up camper, where my battery is not in a compartment, it actually sits on the A-frame outside the trailer. You don't want your connections getting all corroded up so this keeps this connection nice and free of moisture. So that way we can have this mounted outside the trailer and still use it. And what's even cooler about this dust cap here If we look, this is actually a sleeve that slides on here. And what this will do is we can leave this sleeve in place, plug it in our cable and that whole sleeve actually seals up around here. So we can have this just sitting on right outside. It can be raining outside and we're charging up our batteries and this is going to help protect us from the moisture as well. With the regular, just clip on leads. It doesn't have that sleeve on there. So you can see here where, when we plug these two together, it's, there's nothing, there's no protection there moisture could get down in there and potentially causes us an issue if we're just going to leave, just sitting outside. So now we're just gonna hook it up. We're just going to clip our connections on here and let's head over to our charger now and see what we got going on. So we've gone ahead and powered up the charger and we can see here, it went straight past step one, which is a low voltage check to make sure it's above two volts, which we are. It's gone on to step two, where it will do a pulse will wake up and it's just testing the battery looks like everything passed there. So it's now moved on to the next test, passed its testing, and we've gone into either the advanced save or the pulse save. The save light lights up for both step four and step five. Step four is an advanced save for highly sulfated batteries and step five is just a pulse save. If you just hook this up, like we did to our batteries on the trailer, it will skip step four and go straight to step five. In order to use the advanced save mode for highly sulfated batteries, you'll need to physically remove the battery from the trailer. It can't have anything else connected to it in the circuit. So you can just disconnect all the wires or completely pull that battery out of there and then charge it, and this is recommended if the battery is severely discharged. Typically if you discharge to the point where it's down below like five volts, somewhere where it's heavily discharged, it's recommended to remove it and charge it just by itself so we can go into that advanced mode to try to recover that battery and keep the most capacity as possible in that battery. And if it does pass and was on to step five, which is a pulse save, where it just prepares the battery for a full-on charge, it will stay in the save mode for between 15 minutes up to two hours. Just to make sure that it's preparing our battery properly we're not going to inject too much voltage into it, and we're not going to do anything that's going to cause the battery to degrade its overall capacity. So once it's completed here, it will then click over to charge and then it will charge our batteries up. That'd be the next step in the process. So this is a smart charger, it's constantly taking measurements and verifying it's doing the right thing. So it's going to be in this mode here for a little bit and the amount of time it stays in this mode is going to depend on the capacity of your batteries, the particular charger you've chose. If you have a higher output charger, it can go a little bit faster. And then again, that all depends on the, how much batteries you've got, the more batteries you have the longer it may take. And it depends on the condition of those batteries. If they're severely discharged they may take a lot longer to go through these modes to get it charged up, versus maybe they'd just been sitting out here for awhile And they've just kind of just drained a little bit from natural sitting versus being actually discharged from all the use, from all your electronics. So we're just gonna give it some time here to let it get through this mode and into the next one. This trailer has just been doing a lot of sitting. So I don't think it's going to take it a very long time on this one cause we haven't really been using the batteries too much. So now that we've moved on to the next step, which is step six, that's our charge mode, we can see the lights lit up there, showing that we're in charge mode. It enters charge mode if it determines that your batteries at least 50% state of charge and that it is no longer sulfated that it's properly recovered it from sulfation. You'll also notice that the amperage light is lit up here. This is showing how much current we're going into the battery. And there is a gauge here. If the lower LED's lit up, that is up to one amp is being pushed into our battery. If it's the second light, which is what we currently have lit, that means you're getting between one and four amps pushed into the battery. And then if the top light's lit up. That's your maximum of five amps. That's gonna be pushing as much in there as possible. And that's only necessary depending on how much it needs to charge. These batteries are likely close enough to being fully charged that it doesn't need that maximum output. Now this gauge here is specific to the five amp, but there is a similar gauge on the other charges from Optimate, but they're going to have the appropriate amount of amperage that that charger is rated for. After the charge process, it'll go into the optimization process. This is going to have the same lights lit up as the charge process. The difference here is going to be that in the optimized mode, it's going to enter that once it gets to about 14.4 voltage on the battery there, and then it's going to change its strategy slightly to pulse the amperage into the battery, to help balance the individual cells of our battery with your AGM's and your standard 12 volt batteries you're going to have six cells inside of there so we can use this process to balance those because if they're not balanced, when you go to take current out of it to power lights or whatever else in your camper, it can discharge an individual cell further than the others, if they're not balanced and that could potentially cause damage to that individual cell. So this is just going to help further extend the life of your battery by evening out those cells. It can stay in this mode for up to 72 hours, and it may even repeat steps 4, 5, 6, and 7 as necessary to optimize your battery and bring it back up to a hundred percent state of charge. Now all of these chargers are going to have this optimize feature where it will repeat some of the cycles to give the best charge for your battery to maximize the capacity that it has available to it. The only difference is this one has a nine step process so there's a couple of extra steps that it repeats for like desulfation stuff like that. These ones still do repeat their steps to get it up to a hundred percent charged, but they just don't have quite as many steps that they go along with and they're still going to do a great job of charging your battery. It's just the more steps that has, the more capacity you're going to, able to maintain in that battery for a longer period of time. It's just a better charge strategy. So you're not going to lose as much. Every time you take your battery and you discharge it and then recharge it, you are going to lose some of its capacity, but the better your charge strategy, the more of that capacity, you're going to be able to maintain. So it's been about an hour and a half now and we've come back and we can see that it is fully charged all the way up to 100%. And with just this green light on here at the end, that indicates that we're between 80 and 100% charge. It's basically all the way fully charged. And we're now just going to be in a maintain mode where it's just going to ensure that our battery stays fully topped up to help keep it from desulfating. This is just kind of a maintenance charge at this point, just to keep it topped up, kind of like a battery maintainer. So when you look at here where it says maintain this, lets us know that we, that we're in entered the final step of charge mode. It's maintaining the battery and the color of the light that's lit here tells you the health of your battery. If it's just the green light, that's telling you that your battery is perfectly good and it's likely charged to between 80 and a hundred percent. If it's yellow, you're likely had a farely worn out battery that can only charge up to between probably 40 and 75% of its original charge and that's just all that it has available to it. And if you just had the red light lit up, it's probably 50% or less of its maximum charge that it's got available to it. You should probably consider replacement at that point. Sometimes you can see two lights, for example, maybe just, maybe you'll see the yellow and the green. That just means that your current health and state of charge in between those two, that'd probably be between yellow and green. I would say that's roughly about 60 to 80% in there. And you could also see yellow to red and that's probably roughly 40 to 20% in there. So now that we know that our batteries are fully charged and we've got the confidence that the diagnostic test has given us the green light that our batteries are in good health. We know that we're ready to hit the campsite and enjoyed multiple hours of power from our batteries..

Customer Reviews

OptiMate 5 Start/Stop Smart Battery Charger - AC to DC - 12V - 4 Amp - MA94JR

Average Customer Rating:  5.0 out of 5 stars   (2 Customer Reviews)

Compact smart charger draws power from a wall outlet to automatically charge and maintain batteries on cars, trucks, SUVs, motorcycles, lawnmowers, ATVs, and personal watercraft. Saves sulfated batteries as low as 2V. Charges 12V lead-acid batteries.


Review from a similar OptiMate 5 in Battery Charger


Review from a similar OptiMate 5 in Battery Charger


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