invertor playing up

[AstonHill]

I have a ring 150W invertor

12v 150w Inverter with 2A USB | Halfords UK

Shop the latest The 12v 150w Inverter with 2A USB is great to use on lots of different equipment rated up to 150w. at Halfords UK

www.halfords.com

running off of a 110amp/hr battery powered by either a large solor panel or a generator

The invertor used to charge up my laptop battery (without laptop running) and my large power tools battery ok. But over the last week things have gotten worse
At first I could charge my laptop off from the invertor in the dark and no generator running to charge battery
Then I was unable to charge my large power tool battery up though the day light, then i was unable to charge my laptop though the day light as it just keep tripping
So now the invertor only works with out tripping when the generator is charging the battery up

 

[Harry Bloomfield]

So now the invertor only works with out tripping when the generator is charging the battery up

Have you bothered to check the voltage, at the battery, when just the battery in use, supply power to the inverter, with the inverter in use?

 

[AstonHill]

no not checked the voltage
it should be more when charging then when not charging the battery, but what should it be when battery is left alone standing?

 

[ericmark]

A lead acid car battery will normally be between 12.6 and 12.9 volt when standing not on charge. Most smart chargers will maintain the battery between 12.9 and 14.4 volt normally one will see a spike as the charger turns on at 12.8 and off again at 14.4 volt. But a car alternator is normally set to 13.8 volt.

Most inverter will auto switch off at around 11.8 volt the one you link to says Input voltage range 11 - 15 volt and 11 volt seems rather low. Most batteries state guarantee void if discharged below 12.4 volt.

The problem with lead acid batteries is the sulphur goes hard over time, and once it goes hard it takes a long time to convert back into H2SO4. I have put a abandoned battery on charge using an energy monitor on the charger so I can record the charge pattern. I had to con the charger but putting a good battery in parallel or the charger would not work, and it sat for 11 days doing nothing then went through the normal charge pattern and seemed to fully charge again.

So likely if over a time the battery has been getting lower and lower, then likely it will need to be left on a smart charger for a week to fully recover. Old battery chargers could over charge the battery, regulated battery chargers will float charge at around 13.6 volt, but this will not fully recharge the battery as some cells will be better than others, where the smart charger will pulse the charge lifting the battery to 14.4 volt then allowing it to fall to 12.8 then charging it again.

During Colvid I put the Jag battery on charge and clearly it linked to Jaguar at 11.50 am every day as I would see charge rate rise that time every day, I left it on charge for a week at a time, the charger was rotated between 3 cars. The Kia had a floated battery and needed a lot more charge to the Jag which used a absorbed glass mat type.

 

[Harry Bloomfield]

But a car alternator is normally set to 13.8 volt.

The rest is OK, but the usual car alternators run quite a bit higher than that - usually around 14.4v.

 

[ericmark]

The rest is OK, but the usual car alternators run quite a bit higher than that - usually around 14.4v.

Vehicle alternators can be set higher, it is a compromise due to the vehicle not really running long enough to recharge the battery fully, but the standard setting for a Lucas 17 ACR alternator was 13.8 volt, the open circuit setting for a Lucas two bobbin regulator on a C40 dynamo was 16 volt although it would never reach that voltage in normal service, and the regulator in the 17 ACR did not actually regulate the output it used a mark/space ratio either fully on or fully off, the semi conductors could not have taken the heat to regulate the voltage, we would actually use an oscilloscope in the test bed to see the charge pattern as if the pattern was erratic that was a warning the regulator was on it's way out.

Tractors could have a special version of the 17 ACR alternator with a sensor under the battery to reduce charge rate when the battery got hot, the CAV version with external 440 regulator had lo,med,hi settings except for the bus version where the AC408 alternator had a resistor connected to M1 and M2 and had current as well as voltage regulation. The Delco Reme and Paris Rhone both did brushless alternators but not in the style of the higher voltage mains alternators with rotating diodes, but the fingers of the rotor rotated over a static exciting core.

The Grove Cranes used a Delco with a three phase auto transformer with both 12 and 24 volt outputs, but only the 12 volt side was regulated. Each service batteries would be swapped around it had 24 volt start and 12 volt run. I have worked on vehicle charging for quite some time, the narrow boats have a device to take the output from two alternators and hold the output low enough to cause max output then inverters feed 13.8 volt well some times lower to the traction battery and then 14.8 volt to the main battery bank and monitor the voltage after each pulse to set the charge rate, if you look at Sterling products there are many alternator to battery and battery to battery chargers, the whole concept of split charging had to change with the advent of the stop/start technology with cars, the anti snake devices were activated by battery voltage so when the car stopped charging the anti snake device stopped working, so today we use battery to battery chargers and the split charging idea is now old hat and dangerous.

But the problem remains what ever method is used lead acid batteries take time to charge, use too much current all you get is hydrogen gas, so for me who only uses his car for a few miles a month, there is no option but put it on a smart charger every so often to bring the batteries back up, I have a large 4x4 and small run about, I need the 4x4 to tow the caravan, but it only has a few weeks of use a year, so it sits at top of the drive so it can be charged from time to time.

I use a Lidi charger, less than £20 and they are a god send, as I can simply connect switch on and forget, the old chargers one had to top up cells, and they were completely unsuitable for sealed batteries, specially the VRLA or AGM type.

 

[Harry Bloomfield]

Vehicle alternators can be set higher, it is a compromise due to the vehicle not really running long enough to recharge the battery fully, but the standard setting for a Lucas 17 ACR alternator was 13.8 volt, the open circuit setting for a Lucas two bobbin regulator on a C40 dynamo was 16 volt although it would never reach that voltage in normal service, and the regulator in the 17 ACR did not actually regulate the output it used a mark/space ratio either fully on or fully off, the semi conductors could not have taken the heat to regulate the voltage, we would actually use an oscilloscope in the test bed to see the charge pattern as if the pattern was erratic that was a warning the regulator was on it's way out.

All I can say, is that is not my own experience of car alternators. All have outputted nearer 14.4v when cold, though I note it can reduce somewhat as the alternator warms up. I read somewhere that is a deliberate design feature, to help put charge into the battery, from a cold start.

 

[ericmark]

All I can say, is that is not my own experience of car alternators. All have outputted nearer 14.4v when cold, though I note it can reduce somewhat as the alternator warms up. I read somewhere that is a deliberate design feature, to help put charge into the battery, from a cold start.

Today with stop/start technology the charging is controlled by the engine management and it may well have some method of rapid replacing of the start current. But a stand alone alternator where the use is unknown, would be set to 13.8 volt, I know the transit van did have a special many years ago with a higher float charge voltage, and I am sure there are others, but we have no idea when building an alternator if it will go on a compressor or a car, clearly the compressor does not have day running lights.

For the emergency pumps we had for fire fighting, there was a battery charger to ensure battery always fully charged, this was set to 13.4 volt rather that 13.8 so it would not dry out battery. However two way radios are designed to be vehicle mounted, and these were designed for a 13.8 volt supply, and when using a battery which was not being charged some models would transmit well under the rated 25 watt, I know the Icom IC 290 was like that, where the more common FT290 from Yaesu would work 11.5 to 16 volt at same 2.5 watt output.

I will admit I left the auto electrics around 1988 when I went to work in Sizewell, I did both mains and auto from around 1975, I slowly moved to doing more three phase at 400 volt and less at 24 volt as time went on, but the vehicle training helped work on industrial machines and on the second seven crossing I was head hunted to work on the straddle carrier due to the mixture of voltages used, but things which can lift and carry 200 ton are not that common, so never worked on one again.

 

[AstonHill]

I tested the battery in the day time, and even though the solor charger said 28V (2 LAB) the battery in question read between 11.5-11.75

PS I am drawing a 3.5W LED at the time

 

[AstonHill]

Just tried it now in the dark and it reads 11.38 (seam more steady then before)

 

[AstonHill]

Most inverter will auto switch off at around 11.8 volt the one you link to says Input voltage range 11 - 15 volt and 11 volt seems rather low. Most batteries state guarantee void if discharged below 12.4 volt.

Where dose it say that please as I cant see it in the description

 

[davelx]

Where dose it say that please as I cant see it in the description

Read the specification.

 

[Harry Bloomfield]

Where dose it say that please as I cant see it in the description

It doesn't need to - if it didn't switch off once the battery voltage drops, then it would permanently ruin the battery.

 

[AstonHill]

I tested the battery in the day time, and even though the solor charger said 28V (2 LAB) the battery in question read between 11.5-11.75

i have just tried my other battery the one that i do not draw from and it reads 13.38V

 

[AstonHill]

It doesn't need to - if it didn't switch off once the battery voltage drops, then it would permanently ruin the battery.

how is that then? will it not recharge again?