Bongo Fury

Hi,

Was wondering if anyone had any experience with these types of inverters ?

When I have my electric hookup plugged in - everything works fine and off the main electics. However, when I try to switch to the Leisure battery via the inverter, it makes this constant whining or beeping noise and that suggests, from what I have read, that there is low voltage IE a low battery?

Can anybody clarify that?

Do I need a new Leisure battery ?

Well without some measurements made on the LB its impossible to tell!
You really need to check as a minimum the voltage on the LB terminals when there is no load connected and its fully charged, it should be around 12.6 volts after its been resting for about an hour from being charged.
Then you need to measure the voltage at the battery terminals when there is a load applied like the inverter, it ought to stay at around 12.4 - 12.6 volts if its in good condition.
After that you need to measure the voltage at the input terminals of the inverter itself to make sure that there isn't a voltage drop in the wiring, connectors or fuses that feed the inverter.

One other aspect to bear in mind is that inverters are not the best way to get the max from the battery, there usually quite poor efficiency wise unless your spending a lot of money, typically only 80% efficient so your throwing away 20% of your batteries charge! Also no no battery is going to have the capacity to do any sort of heating either for cooking or space heating, you need to use fuel based products gas/diesel/petrol etc. for those purposes.

g8dhe wrote: Mon Sep 27, 2021 7:20 pm Well without some measurements made on the LB its impossible to tell!
You really need to check as a minimum the voltage on the LB terminals when there is no load connected and its fully charged, it should be around 12.6 volts after its been resting for about an hour from being charged.
Then you need to measure the voltage at the battery terminals when there is a load applied like the inverter, it ought to stay at around 12.4 - 12.6 volts if its in good condition.
After that you need to measure the voltage at the input terminals of the inverter itself to make sure that there isn't a voltage drop in the wiring, connectors or fuses that feed the inverter.

One other aspect to bear in mind is that inverters are not the best way to get the max from the battery, there usually quite poor efficiency wise unless your spending a lot of money, typically only 80% efficient so your throwing away 20% of your batteries charge! Also no no battery is going to have the capacity to do any sort of heating either for cooking or space heating, you need to use fuel based products gas/diesel/petrol etc. for those purposes.

Hi,

I currently have my Bongo in with my Mech and he tested the leisure battery (and the Van battery) and said they were both fine in terms of holding the charge etc also said they were relatively new batteries and that.

So I think if the battery is fine and it must be related the 'input terminals' that feed the inverter

On that note, he did pay reference to 'a box' (sorry I can't remember what it's called but I do know where he was talking about) that connects both the batteries and sits somewhere in the middle of the engine bay.

He mentioned that some of the connections were eroded and that by replacing that it could solve the problem?

He hadn't got in and out of the van to really thoroughly test it though because there were some other matters which are in need of being tended to first (posted another thread about it) and simply put, he didn't want to get the inside of my camper all dirty..

I have an Eberspaecher 801 fuel based heater and up until recently, even after the above post, it was working fine. However, the last time I took it out, a couple of weeks ago, it wouldn't fire up despite being connected to EHU and it was producing a F11 fault code, which when I looked it up in the manual, it pointed toward something to do with low voltage.

Is this a fresh problem or related to the above?

Appreciate the help!

Thanks!

JF117 wrote: Tue Nov 02, 2021 3:27 pm On that note, he did pay reference to 'a box' (sorry I can't remember what it's called but I do know where he was talking about) that connects both the batteries and sits somewhere in the middle of the engine bay.

Its possibly the Split Charge Relay (SCR) the relay operates when the alternator is running and generating power and so both batteries are charged in parallel, when the alternator is not generating then th relay releases and the two batteries are separated from each other so that only the leisure battery (LB) is being used. The SCR connections shouldn't have any effect on power being drawn from the LB at all, but if they are corroded then charging of the battery might be affected.

The fact that the Eberspacher heater is also reporting low voltage as well as the Inverter then that would suggest that if the battery tests OK (he did check the LB and not the SB didn't he ??? MAKE CERTAIN!!) then the wiring might be a problem or connections via any fuse boxes and switches.

g8dhe wrote: Tue Nov 02, 2021 3:41 pm

JF117 wrote: Tue Nov 02, 2021 3:27 pm On that note, he did pay reference to 'a box' (sorry I can't remember what it's called but I do know where he was talking about) that connects both the batteries and sits somewhere in the middle of the engine bay.

Its possibly the Split Charge Relay (SCR) the relay operates when the alternator is running and generating power and so both batteries are charged in parallel, when the alternator is not generating then th relay releases and the two batteries are separated from each other so that only the leisure battery (LB) is being used. The SCR connections shouldn't have any effect on power being drawn from the LB at all, but if they are corroded then charging of the battery might be affected.

The fact that the Eberspacher heater is also reporting low voltage as well as the Inverter then that would suggest that if the battery tests OK (he did check the LB and not the SB didn't he ??? MAKE CERTAIN!!) then the wiring might be a problem or connections via any fuse boxes and switches.

I am quite sure he said he checked both batteries but I will clarify that when I speak to him next.

It would seem that the problem points toward connections beyond the battery, so I'll forward your point regarding the SCR.

On your point regarding the alternator - I have driven the van for hours at a time and still experienced the same issue though. I have also attached the EHU over night, in order to try and charge it, and still experienced the same issue. All of which led me to believe the battery was not holding charge, and thus your point on the SCR would make total sense. However, if the Mech is adamant that the battery is not the problem and I have effectively charged by both EHU and driving (alternator) methods, what would that suggest the problem is?

Another way of putting it, if the SCR being corroded effects the charging of but not the power being drawn from the LB yet the Mech says the battery is fine, then what would that be?

By that logic and from the above, I would have, at least a little bit of, a charged up battery from driving or EHU but when I try to draw power from it, the whining noise still happens.

Think it must be the wiring or the connections via fuse boxes and switches then - which is something the Mech also thought.

Correct to say, that's probably the best next step in terms of testing?

Everything is pointing towards the wiring of the 12v supply around the van itself to the Inverter and heater. Even if the battery wasn't holding charge if the EHU or the Alternator are charging the batteries then you would expect them to supply the power rather than the battery itself, from what you say that isn't happening so that points to the wiring from the heater and inverter to the source of power. I think you need to spend time with a meter checking the voltages at the devices and then back along the wiring to any control panel and from there back to the power sources.

g8dhe wrote: Tue Nov 02, 2021 4:19 pm Everything is pointing towards the wiring of the 12v supply around the van itself to the Inverter and heater. Even if the battery wasn't holding charge if the EHU or the Alternator are charging the batteries then you would expect them to supply the power rather than the battery itself, from what you say that isn't happening so that points to the wiring from the heater and inverter to the source of power. I think you need to spend time with a meter checking the voltages at the devices and then back along the wiring to any control panel and from there back to the power sources.

Agreed, and tbh that's what the Mech said too (just didn't want to hop all over my well-kept van getting it dirty!).

I'll try and report back with findings for the future reference of any other members!

Thanks for your help!

JF117 wrote: Tue Nov 02, 2021 5:01 pm

g8dhe wrote: Tue Nov 02, 2021 4:19 pm Everything is pointing towards the wiring of the 12v supply around the van itself to the Inverter and heater. Even if the battery wasn't holding charge if the EHU or the Alternator are charging the batteries then you would expect them to supply the power rather than the battery itself, from what you say that isn't happening so that points to the wiring from the heater and inverter to the source of power. I think you need to spend time with a meter checking the voltages at the devices and then back along the wiring to any control panel and from there back to the power sources.

Agreed, and tbh that's what the Mech said too (just didn't want to hop all over my well-kept van getting it dirty!).

I'll try and report back with findings for the future reference of any other members!

Thanks for your help!

Mech took the battery out and charged it overnight, sustained beep noise from inverter went away..

Needs further investigation to be completely certain because it begs the question, why hasn't it been charging whilst the engine running &/OR electric hook up being connected?

JF117 wrote: Tue Jan 11, 2022 12:45 am

JF117 wrote: Tue Nov 02, 2021 5:01 pm

g8dhe wrote: Tue Nov 02, 2021 4:19 pm Everything is pointing towards the wiring of the 12v supply around the van itself to the Inverter and heater. Even if the battery wasn't holding charge if the EHU or the Alternator are charging the batteries then you would expect them to supply the power rather than the battery itself, from what you say that isn't happening so that points to the wiring from the heater and inverter to the source of power. I think you need to spend time with a meter checking the voltages at the devices and then back along the wiring to any control panel and from there back to the power sources.

Agreed, and tbh that's what the Mech said too (just didn't want to hop all over my well-kept van getting it dirty!).

I'll try and report back with findings for the future reference of any other members!

Thanks for your help!

Mech took the battery out and charged it overnight, sustained beep noise from inverter went away..

Needs further investigation to be completely certain because it begs the question, why hasn't it been charging whilst the engine running &/OR electric hook up being connected?

Not that anyone on this board is probably monitoring this post but just incase someone is Googling for solutions on this I thoought I'd relay my findings.

Essentially, bottom line is that the battery needs replaced but to expand on some of my technical findings:

The inverter, as per the specification, makes these noises off the back of the fact its not receiving a solid 11.4v volts. I confirmed this through buying the ctek 0.8 smart charger, taking the battery out and giving it a good charge then going through some different tests with a multimeter.

Tests being, engine off, engine on, switching inverter on, switching heater on & taking readings each time to see how the battery was being affected. I probably could have done this so much more simply by having a load tester or something - but I didn't so I just did these things step by step and took a reading each time.

Immediately after the charge things didn't look great for the battery right away because the reading was 12.4v which from what I've read isn't a great reading right away.

Then under load, and with the different tests, it was barely just sitting above 11.4 volts, which is what the minimum the inverter needs as well as the heater. When they're both on at the same time, which would be the general assumption if going anywhere off grid, it just wouldn't stand up to the task at all, so I knew right away the battery needed replaced. Given that my findings were quite conclusive on that, I didn't even bother testing with the EHU and went ahead and bought a new Yuasa battery [L26-AGM] which is an exact like for like in terms of fit, considered fairly high grade and I could put my hands on it right away (so might have over-paid for it in that respect - halfords).

I've got that on a charge atm anyway, just so I can assess the quality of the new battery and if it's not standing up, bring it back and swap it for a better one.

Thought I'd report back my findings anyhow, to anyone on this board who cared, and then for anyone elses benefit who might be experiencing the same problem.

I know some of the boardies on this might also be thinking that this is terribly obvious, but I learnt alot and the experience served me well because through the research and googling I did, it's considered very good practice to take out your leisure battery and keep it nice and charged ahead of whenever one wishes to set out on their adventures, again something that may be considered extremely obvious, but it wasn't for me and so I'm glad I'm better off for it!

Whilst it's probably always going to be specific camper to camper, for anybody who has the same inverter and might be confused about it, I learned that of the three settings:

I = bypasses the switch & turns the inverter on constantly
0 = off completely
II = diverts the inverter to the switch above my sink so that I don't need to duck down underneath the sink and reach into the cupboard to switch it to one

Sustained beeping noise = the inverter isn't getting a constant flow of 11.4 volts from the LB and as some of the posters here said, shouldn't even be down that low to begin with anyway.

Thankyou.

One think to be aware of is (and I only found this out recently) that AGM batteries charge at a different voltage to regular lead acid batteries.

Your CTEK optimiser should charge AGM batteries correctly but the alternator / split charge system won't be charging at the correct voltage.

Apparently AGM batteries should only be used where the original system was designed for them.

They work with a lower charge rate but will never at be at their optimum.

Many standard 12v chargers don't charge them correctly either.

So definitely worth giving it a charge with your CTEK regularly to ensure it gets a proper charge.

Yes great to have the feedback.

As to AGM batteries yes there is so much misleading advertising about there use in cars, fine when the alternator/car is designed for them but a poor idea if using a standard alternator. They were originally used for wheelchairs, golf carts and devices that would normally be used then plugged into the dedicated charger until next use. When you put any of the modern batteries into a vehicle that wasn't designed for them its a recipe for throwing your money way as they just won't last for the advertised life!

I've got to admit to being guilty of that with AGM batteries. I thought because they were supposedly better and better technology that they would make a good replacement for the bongo leisure battery. Fortunately for me when I bought the last one the deal on a non AGM one was too good, so I stuck with that.

I was completely ignorant to the differences. It is only since having a Land Rover with start stop technology that I discovered the differences and the fact that I shouldn't really use my (non AGM) charger to charge it off the vehicle. I had to replace the battery and had to ensure that it was another AGM had the higher output from the alternator apparently does non AGM batteries no good.

They don't really advertise these differences though, you have to do some digging around to find it out.

sotal wrote: Mon Jan 24, 2022 8:20 am Your CTEK optimiser should charge AGM batteries correctly but the alternator / split charge system won't be charging at the correct voltage.

Apparently AGM batteries should only be used where the original system was designed for them.

What is the optimal system / correct voltage?

g8dhe wrote: Mon Jan 24, 2022 10:40 am Yes great to have the feedback.

As to AGM batteries yes there is so much misleading advertising about there use in cars, fine when the alternator/car is designed for them but a poor idea if using a standard alternator. They were originally used for wheelchairs, golf carts and devices that would normally be used then plugged into the dedicated charger until next use. When you put any of the modern batteries into a vehicle that wasn't designed for them its a recipe for throwing your money way as they just won't last for the advertised life!

So should I actually take it back? I did pay a bit of money for it (£175).

I was intending on taking out and keeping charged until use each time anyway, but since I probably still can take it back - do you think I should?

Voltage wise,

It isn't an easy answer, as it varies for an optimal charge. There are (IIRC) 3 different charging stages, the voltage alters for each of these stages.

Regular lead acids charge at around 13.8-14.4V

Depending on the stage AGM require 14.6-14.8V

I believe that battery temperature also plays a part in the voltage supplied. Our AGM battery on our car that requires an AGM battery has a Battery Management System connected to it. It has various status readings etc that are readable via the OBDII diagnostics connector. It also requires the BMS to be reset when you install a new battery, which originally was done at the dealer but can now be done with a cheap OBD device.

The specifics of how an AGM battery charges and the stages, go over my head. There is lots of information on Google though. Have a read and make your decision from there.