Split Charging, Voltage Sensative Relay VSR - How to, review and test

In this video we talk about using Split Charging and Voltage Sensitive Relays to charge your leisure battery from your alternator and keep your starter battery topped up.
We also test out a Banggood Voltage Sensitive Relay.
Product Link
www.banggood.c...
0:00 Intro
1:21 Overview
2:14 What is a VSR?
4:12 Demo
6:35 Conclusion
#vanlife #battery #vsr
Music
SOLO ACOUSTIC GUITAR by Jason Shaw freemusicarchiv....
Creative Commons - Attribution-ShareAlike 3.0 Unported- CC BY-SA 3.0
Free Download / Stream: bit.ly/_solo-a...
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Any information provided on this channel is intended for general guidance only and must never be considered a substitute for advice provided by a qualified professional.
Topics in my videos may have potential safety implications for you and your van.
Any information I share in this video is purely my opinion. What you chose to install or how you install it, is entirely your choice and responsibility.

[@keithpringle1103]

Shared on SBC group, Cheers

[@Merlin-Power]

An informative and well-made video. Good stuff 👏

[@tehdreamer]

Thanks for the video, I thought something was wrong with my VSR when it keeps triggering on from the leisure batteries being charged from solar panels. Given that I have AGM batteries and the starter batt is flooded lead acid, I don't really want to have them always connected as the solar charger controller is configured for a specific AGM charging profile and that could cause problems if the starter is connected via the VSR, however, I don't know for sure. Thanks for your suggestion I will put a switch on the ground wire of the VSR to switch it off when parked up and only use it when driving when my leisure is flat during winters days. Later on will get lithium phosphate batteries and get a DC to DC charger to go with them but for now VSR will do.

[@darrengee9988]

Thanks for this, well explained useful information

[@charliesilva3475]

I am new to cars... I have a second battery that is connected to the primary in a parallel. I have a several questions... 1) having a smart battery splitter relay will the car start while the primary is drain and the second is 80% full? Would it be better to have it without this relay if it can have the second battery start the car while the first battery is drain? 2) how would this work with a solar panel; does it need another smart battery splitter relay for the solar panel? 3) what type of wire size it need? I use for both batteries a wire gauge 0. Do I need this size or is just a recommend wire that comes with the relay is enough? Would the different gauge wire size make a difference or not? I forgot I have a Toyota Celica 2000 GTS. It says that the alternator is rated at 80amps. My battery setup is followed: Primary battery is 12v with 50amps Second battery is 12v with 90 amps

[@kevinhartle4494]

Thanks for the video, they are always informative and well made. A note of caution I would add is to be careful using a VSR if you have Lithium Ion leisure batteries. These batteries have very low internal resistance and can pull a large current from the alternator. Depending on the size of your battery bank, it is possible for the high current drain to overheat and burn out the alternator.

[@ExploreVanUK]

Thanks Kevin, glad you like the videos - You make a great point - I would probably go a step further to say I wouldn't recommend using a VSR with Lithium batteries at all, not only for the point you make, but also from the perspective that a VSR just isn't intelligent enough to charge a lithium battery effectively. Considering the cost of Lithium Batteries I would suggest it's definitely worth factoring in a Smart Battery to Battery Charger with a Lithium battery profile as an alternative to a VSR to avoid any risk of damage to the system battery and to get the most for your money spent. I probably should have mentioned this along with the Smart Alternator, thanks for flagging

[@hjpinternet1244]

Is there a way of knowing what sort of amperage my alternator can produce without being damaged . This product says 140 amps but what does that refer to ? Thanks J

[@ExploreVanUK]

Hi , the 140 Amps is the maximum Amperage the Relay can switch / flow safely. It's unlikely that your alternator will ever feed more than that to the battery. You can check the maximum output of the alternator by checking the make / model fitted just to be sure.

[@ioannisvarkoulis6081]

Thank you for the video.On my boat I have. 2 batteries connected with a VSR.I also have a Victron charger with two output.Could I connect them to each battery or would I harm the VSR?

[@superdog1947]

so when you press the small button it disconnects the system from the main vehicle battery instead of having to install a separate cut off switch, as vsr work both ways always worried about solar cooking the engine battery

[@ExploreVanUK]

Thats right when it’s set to manual mode. (3 second hold of the button) it override the automatic selection so you can connect or disconnect irrelevant of the states of the batteries.

[@superdog1947]

@@ExploreVanUK thanks

[@adriancross8067]

Hi wating your videos , . All good but can you simply tell me ... My setup is small 2x 150w panels 2 x 110 amp hour batteries 30 amp mppt charge controller . As im getting mixed up by what is the best way to set these all up as 12 volt set up .please help thankyou

[@ExploreVanUK]

Hi, drop us a message using the contact form on our website www.Explorevan.uk and we’ll send you over a diagram.

[@adriancross8067]

@@ExploreVanUK i have messaged by email to you ok thanks

[@adriancross8067]

Sorry but theres nothing from you i can see ? On email address i sent you ?

[@adriancross8067]

I have remessaged you

[@ExploreVanUK]

@@adriancross8067 HI, I've resent reply from a different email address just in case its getting caught somewhere, might be worth checking your spam box.

[@postdiver]

Great video and you have helped me understand a bit better. One question, should I leave the spilt charger on all the time? I have the same one you are showing in the video Thank you

[@ExploreVanUK]

Hi thank you - glad it was useful! We always left ours on all the time, that way the leisure battery gets charged whenever we drive, and starter battery gets charged by the solar if we are sat in in one place all the time and the Leisure battery gets full. As we have now moved to a a Lithium battery we can;t use a VSR anymore :-( so saving up for a B2B charger.

[@jlh9847]

Hey , i have the Cargo vsr fitted in my campervan which i had the conversion done with a garage , i have solar plus split set up but i keep having a clicking noise that comes from the cargo box …… any ideas what this could be as the noise doesn’t happen none stop but annoying when starts. Many thanks in advance.

[@ExploreVanUK]

Hi this i not too unusual and suggests one of the batteries is hovering around the cut in / out voltage. It could indicate one of the batteries is not performing very well or it could just be a symptom of the way the solar is connected. I find being able to manually isolate the VSR with a switch in the -ve lead is a good way to keep control of this.

[@SimonWatson-nx1kt]

Can you use a VSR to supply a power block for accessories that would isolate when the voltage drops?

[@ExploreVanUK]

Yep, as long as the load doesn't exceed the rating of the VSR wiring etc. Just check that the voltage cut in and cut out matches the voltages you want the accessories to go on and off at.

[@andrewbrown6522]

Any idea if solar input will trigger the relay to stay open while starting the engine? Seems like it would and potentially burn out.

[@ExploreVanUK]

Hi, yes if the solar is putting in enough to increase the voltage of the leisure battery over the threshold it will activate the relay. If the starter battery was in a depleted state and the starter motor were to try to draw a higher current than the cable from relay to battery was capable of from the leisure battery it would blow one of the fuses you would have to protect the cable, these would be rated lower than the relay so the relay wouldn’t be damaged. In reality if the starter battery was in a state capable to start the engine this wouldn’t happen as all the power would come from the starter battery.

[@andrewbrown6522]

@@ExploreVanUK I cant believe i didnt think about using a fuse to protect against that. Lol I was thinking of using a bosch 5 pin to control the ground to the VSR in order to be off when starter is cranking. Thanks for the quick reply!

[@Hjexecutivetravel]

I’ve had one of these installed on a vclass 2018. I was questioning the installer as to whether it should be on my vehicle As I think it’s a smart alternator as it’s a modern vehicle. It does work but sometimes my battery warning light comes on then goes off. Do you think it’s the wrong one on my vehicle ?

[@ExploreVanUK]

If you are unsure, you can carry out the following test. Using a voltmeter attached to the vehicle (via a cigarette socket would work), take it out for a 20-40 min drive with another person. During the drive, have the other person monitor the meter. Should the voltage go up and down between around 12-15V then the vehicle has a smart alternator and you will need to use a DC-DC charger. If it stays steady & consistent at about 14V or so then you will have a fixed voltage alternator and be able to use a VSR.

[@bogdan.dobrowolski]

What would you suggest in a situation where I have a STANDARD NOT smart alternator and I want to change the battery from AGM to LiFoPO4. Everyone informs that VSR is dedicated to standard alternators and DC/DC chargers to EURO 5 OR 6. It is not often said what kind of batteries can or should not be used with VSR or DC/DC. Everything seems to be that if I buy a LiFoPO4 battery and connect it to the VSR, then this battery will blow up my alternator. So what to do in this situation and is there any reasonable solution ???

[@ExploreVanUK]

Hi this is exactly our situation. We have a non Smart Alternator and changed to LiFePO4 battery last year. You are right that VSR is not ideal for charging LiFePO4 as it has no profiles and the voltage is unlikely to go high enough to get it full. B2B / DC-DC chargers are needed for Smart alternators but can be used just as well on none Smart alternators. We use a Sterling charger which lets us charge at up to 60 amps, so gets the battery topped up in no time and has a LiFePO4 profile so we know it’s doing it in the best way to keep the battery healthy.

[@bogdan.dobrowolski]

@@ExploreVanUK THANKS !!!

[@paulcottam128]

What size cable would you recommend to supply feed and outlet to batteries with this VSR

[@ExploreVanUK]

Afraid this will depend on your alternator output, length of cable and how depleted you expect your leisure battery to be when it is being charged if you want to be able to work it out. I would suggest over sizing the cable to reduce voltage drop and for safety rather than going for the smallest you think is necessary. Always make sure you fuse the supply with a fuse of a lower amps than the cables maximum. 16mm cross section / 80 Amp cable would generally be my goto with 50 Amp fuses.

[@andrewbell3163]

Hi, I fitted a different make of VSR but having issues. When I turn the engine on the LED flicks on and off a few times then stops working. Do you know what could cause this?

[@ExploreVanUK]

It’s hard to say, but theoretically it sounds like as soon as the batteries are connected it is pulling the voltage of the starter battery down below the cut off voltage and therefore the VSR is disconnecting. Then once disconnected the voltage is increasing above the cut in voltage and it’s reconnecting before cycling doing the same. Which could suggest the battery or the alternator are not working as they should. What happens if you don’t have the leisure battery connected to the VSR when you run the engine? Also are you sure the cabling is suitably sized for the load you are pulling through it? As I’m assuming the VSR you’ve used doesn’t have the integrated volt meter. I’d suggest using a multimeter to measure the voltage at the stater battery contact on the VSR and see what happens to the voltage when the VSR activates.

[@andrewbell3163]

@@ExploreVanUK hi thanks for getting back to me. I managed to get it sorted tonight 👍

[@whydontyouaskme]

I can’t find a video showing how fast or how efficient they can be or improved

[@456suzuki2]

I want to fit one but it would be useful to see how to get the cable from leisure battery to engine battery,

[@ExploreVanUK]

In ours we ran the cable from the engine compartment under the van then up into the Leisure battery compartment through the floor. A lot will depend on where you batteries are kept as to what the best route is.

[@johnholland8162]

Brill video - thanks! I have this set up - should I just leave it on automatic the whole time (top light off, bottom red light on)?

[@ExploreVanUK]

Thanks! I just leave ours on Auto all the time.

[@stevedecoded1]

Great channel! Electrical noob here - why does it only give out 4A if it's a 140A relay? Would it take 25 hours of the alternator running to charge a 100AH battery at 4A? Thank you

[@ExploreVanUK]

The relay is rated for a maximum of 140A. A number of factors will impact the amount of Amps a battery will pull. The rating of the alternator, other demand on the alternator and the state of charge of the battery being charged. A battery with a low state of charge will pull more amps and as the battery charges you will see the current drop. In this example the battery was already pretty well charged and therefore the current was 4amps had it been lower you may have seen 10 or even 20 amps. With a 100ah battery you really shouldn’t be letting it drop below half full before charging or you will start to damage the battery so you only need to get 50ah into it. If it were half full the current you would see is likely to be higher to start with and will then drop as it gets towards full. If you want to maximise the charging from the alternator a Battery to Battery charger is more effective as it uses smart charging profile to get as much into the battery as quickly as it can, keeping the Amps high, but obviously costs a lot more. Solar is our main means of charging our leisure battery, the feed from the VSR just keeps us topped up as we drive if we have poor weather.

[@Urge38]

and what if you require different voltages ???? starter battery and say a LifePo4 require different charge paramotors

[@ExploreVanUK]

This would need a B2B charger with a Lithium Battery Profile. 2 years ago when we made this video LiFePO4 batteries were a lot more rare than they are today.

[@RabMac108AT10six]

Hiya Pal Ive hooked up my VSR (same as yours) to a 160AH Red Tiger leisure battery in the boot of a 2006 Vauxhall Astra. The VSR doesnt come on until i hold the on/off button and the display shows around 12.7 V. What is the purpose of the on/off switch is it safe to leave it "on" with the display showing 12.7 while the engine is off? Or should it be swirched off completely overnight? Any help appreciated bud.. Just starting out here and battery is for night heater and ham radio while camping.

[@ExploreVanUK]

Hi, the relay is in auto mode when the blue LED is out. if you tap the button this will activate the display for a short period showing the voltage of the highest battery. It is normal for the display to go off to save power. If you are seeing 12.7v then the Relay will not be active (the little RED LED will be off) so the batteries aren't connected together. When one of the batteries rises above 13.3 (eg when you start the engine) it will activate the little Red LED will come on and it will connect the batteries together. When you stop the engine, once the batteries drop below 12.8v the relay will disconnect and the little RED LED will go off. By pressing and holding the button and the blue LED coming on - you have put the relay into manual mode and can connect or disconnect the batteries as you wish irrelevant of the voltages by tapping the button. If you leave them connected like this and the relay activated then you run the risk of flattening your starter battery. I would recommend leaving the relay in Auto mode (Blue LED off) and let it do it thing.

[@RabMac108AT10six]

@@ExploreVanUK wow.. Amazing reply and gratefully appreciated. My VSR doesnt show any lights until i press and hold it on and then it just displays 12.7 with a red led showing manual/ auto. If i press the button again it just switches the display and led off. Not really got a clue what it means. When i turn the ignition it displays 14.2v on the cigarette lighter meter in front. The leisure battery (VSR) stays at 12.6v or 12.7v.. I dont think i have a smart alternator on 2006 vehicle.. Any ideas? Thanks for your detailed reply.. Subbed

[@ExploreVanUK]

As a starter for 10 I would check your fuse between starter battery and VSR as it sounds like there is no connection between the two. I'm assuming you have the Leisure battery -ve terminal connected to the car body? If you disconnect the leisure battery from the VSR what voltage is shown on the VSR - if it doesn;t show anything your starter battery is not connected to it. As soon as you start the engine the VSR should read the same as the cigarette lighter as the display on the VSR shows the voltage of the highest battery not just the Leisure battery voltage. You can see this in the video at 4:45 Do you have a multimeter so you can test the connections?

[@RabMac108AT10six]

@@ExploreVanUK hiya pal. Again thanks for your detailed response. Okay I have just been informed that this model of VSR when off (no leds or voltage display) is in auto mode .manual mode when I press the on button. So...I tested voltage at car car battery with engine running 14.4v is displayed. The leisure Battery is testing as 12.59v . I done what you said and pulled disconnected the leisure battery and tested rhe power cable and 13.9V is showing. I'm guessing in auto mode it's just going to take a long time to get the leisure Battery upto around 13v? Do you think I should take it inside and use a mains charger as we hardly really use the car so it may take forever to get it back upto SoC Hope you enjoy your weekend thanks again . Regards Rob

[@ExploreVanUK]

Hi Rob, It sounds to me like your Leisure battery is already close to fully charged and therefore it is not pulling much current from the Starter battery. 12.6v would put it between 80 and 90% charged. You are right, you would be better putting it on a mains smart charger as this will use its various modes to take the battery through Bulk / Absorption phase and in to float to make sure the battery takes as much as it can. VSRs and charging from the alternator are low tech and a simple way of getting some power back into the battery, they are not as intelligent as a Smart Mains Changer.

[@Defkan]

So if both batteries are below charge I can manual override and begin charging?

[@ExploreVanUK]

Technically yes, but you’re likely to find it will do this anyway. As once you start the engine the alternator will make the voltage high enough for the VSR to activate and connect the batteries together.

[@Defkan]

@@ExploreVanUK thanks for the reply. Mine doesn’t seem to be turning on at all, voltage shows at 12.2, would you think a charge of starter battery would help, I’ve not long got the van, and a battery noob but just bought the genius 10 charger.

[@ExploreVanUK]

Yeah 12.2v is low (approx 50% state of charge for Sealed Lead Acid, 60% for AGM) dropping below that will start to cause damage to the battery. The VSR won’t connect until one of the batteries is at around 13.3v whilst being charged (it will say on the relay). I would suggest charging both batteries separately to make sure you are starting from full. They should rest at 12.8v-13v when full having rested for a few hours after charging.

[@Defkan]

Many thanks for this. I’ll get it sorted hopefully.

[@kayone8571]

I’ve subscribed and hope you can reply I gave 3 battery’s in boot and I only have one of those at the moment do recommend I get another one of Those and link it from the one in boot to the 2 spares battery’s that in line much appreciated a reply

[@ExploreVanUK]

Hi, afraid I’d need to know more about your set up and how it is currently wired to be sure. If it were me and I had three Leisure Batteries of the same type and age I would have them wired in parallel being fed by a single VSR.

[@kayone8571]

@@ExploreVanUK hi that’s exactly how they are now as stated how you would

[@DonegalOverlanding]

Some thin wires there...

[@ExploreVanUK]

40 Amp cable protected by 30 Amp fuses.