a battery charging question [as in 'why won't it?']

[Wittenham]

My campervan has a second hand, newly installed Chargemaster 12/25-3 [procured from this parish] and two new 110AH gel batteries.  When I plug in at a campsite, the charging works, green light goes on, fan makes too much noise, batteries get charged.  When I plug into a three pin socket at home, the Chargemaster light shows red, no noise, no charging.

 

Any ideas on what is happening and - even more importantly - what I can do about it?  The manual suggests AC input frequency out of range [whatever that means...] or AC input voltage too low.

 

thanks in advance for any help.  Especially if it includes how to turn off the noisy fan for night time [manual is silent on this point].

[Tracy D'arth]

Are you using the same mains lead in both situations?

When you are home, do the batteries need charging or has the journey fully charged them?

Does another appliance work in the home socket?

What is not common between the two situations, mains lead, any adaptors?

[MtB]

Have you actually measured your mains voltage at home and at the campsite to compare? It might be too low (or high). To check the frequency I think you'd need an oscilloscope but frequency is far less likely to be wrong. The voltage is supposed to be 230Vac and frequency 50Hz. I dunno what tolerance either side of those values is maintained by the National Grid but some googling should bring it up.  

 

My suspicion though is this might be the reason the charger was for sale second hand. It is dead picky about its mains supply....

 

 

 

 

 

[Tony Brooks]

2 minutes ago, Wittenham said:

My campervan has a second hand, newly installed Chargemaster 12/25-3 [procured from this parish] and two new 110AH gel batteries.  When I plug in at a campsite, the charging works, green light goes on, fan makes too much noise, batteries get charged.  When I plug into a three pin socket at home, the Chargemaster light shows red, no noise, no charging.

 

Any ideas on what is happening and - even more importantly - what I can do about it?  The manual suggests AC input frequency out of range [whatever that means...] or AC input voltage too low.

 

thanks in advance for any help.  Especially if it includes how to turn off the noisy fan for night time [manual is silent on this point].

 

Red bit, it needs the fan to keep the internals cool while it's charging, probably with a high current so it may burn out if the fan can be turned off. Answer - turn the charger off.

 

Would home be out in the country at the end of long overhead lines? In theory, the AC mains reverses its direction at 100 times a second, giving a frequency of 50 Hertz. It may be that for some reason your frequency is too far away from 50Hz for it to operate. I think low mains voltage is more likely and it is not uncommon out in the country. If its in town, then I would suggest that you get things checked out at your home.

[springy]

Do you have any other 240v outlets in the campervan, if so do they work when plugged in at home or is the charger the only 240v appliance ?

If they work then its the charger, if not  its the lead or adaptor.

 

springy

Edited August 13, 2021 by springy
typo

[Jen-in-Wellies]

No idea about Chargemaster(?), but I've seen Victron chargers getting upset and refusing to work with voltages at the high end of the National Grid specification. Not all Victron's, but some. It isn't just low voltage that can be a problem.

[Wittenham]

16 minutes ago, Tracy D'arth said:

Are you using the same mains lead in both situations?

Yes, with an adaptor to fit the standard domestic three pin to the chunky blue caravan/boat charging conection

When you are home, do the batteries need charging or has the journey fully charged them?

I think it is still an issue as the charger goes to float when the batteries are full [at the campsite]

Does another appliance work in the home socket?

yes, it does.

What is not common between the two situations, mains lead, any adaptors?

the variables are the adaptor I mentioned above and the source of the electricity.

 

thanks for the quick reply, answers above.

[nicknorman]

Unless the supply is separate from the national grid (local generator etc) the frequency MUST be identical to everywhere else connected to the national grid. You cannot have different parts of the grid on even slightly different frequency. Not possible.

 

The voltage is a possibility, as is the batteries just being already fully charged.

Edited August 13, 2021 by nicknorman

[Tony Brooks]

Posted without quote - deleted

Edited August 13, 2021 by Tony Brooks

[Wittenham]

18 minutes ago, MtB said:

Have you actually measured your mains voltage at home and at the campsite to compare? It might be too low (or high). To check the frequency I think you'd need an oscilloscope but frequency is far less likely to be wrong. The voltage is supposed to be 230Vac and frequency 50Hz. I dunno what tolerance either side of those values is maintained by the National Grid but some googling should bring it up.  

 

My suspicion though is this might be the reason the charger was for sale second hand. It is dead picky about its mains supply....

 

 

My mains supply may be a bit outside the norm.  My house has solar panels connected to a Tesla battery which powers the house via an inverter until its empty, then switches back to grid.  However, when that gave me only a red light on the charger, I bypassed it by plugging into an outbuilding that takes its supply from a separate feed, and got the same red eye.

 

 

[Tony Brooks]

2 minutes ago, Wittenham said:

 

thanks for the quick reply, answers above.

 

But not where hone is located, not that I care.

[springy]

I'd suspect the 13A Plug to 16A socket adaptor.

 

springy

[nicknorman]

Just now, Wittenham said:

 

My mains supply may be a bit outside the norm.  My house has solar panels connected to a Tesla battery which powers the house via an inverter until its empty, then switches back to grid.  However, when that gave me only a red light on the charger, I bypassed it by plugging into an outbuilding that takes its supply from a separate feed, and got the same red eye.

 

“Takes its supply from a separate feed” - are you sure this is connected direct to the mains?

[Wittenham]

21 minutes ago, Tony Brooks said:

 

Red bit, it needs the fan to keep the internals cool while it's charging, probably with a high current so it may burn out if the fan can be turned off. Answer - turn the charger off.

 

Would home be out in the country at the end of long overhead lines? In theory, the AC mains reverses its direction at 100 times a second, giving a frequency of 50 Hertz. It may be that for some reason your frequency is too far away from 50Hz for it to operate. I think low mains voltage is more likely and it is not uncommon out in the country. If its in town, then I would suggest that you get things checked out at your home.

>>  Answer - turn the charger off.

That is what I did!

 

I am in inside the ring road in Oxford, but i do have that solar panel set up as I put in another response.  However, bypassing that did not fix the issue.

[MtB]

1 minute ago, Wittenham said:

 

My mains supply may be a bit outside the norm.  My house has solar panels connected to a Tesla battery which powers the house via an inverter until its empty, then switches back to grid.  However, when that gave me only a red light on the charger, I bypassed it by plugging into an outbuilding that takes its supply from a separate feed, and got the same red eye.

 

 

 

Well there are only two possibilities I can think of.

 

1) Both of your mains supplies are outside of the specification the charger needs. 

 

Or...

 

2) You have a faulty charger. 

 

 

[Wittenham]

1 minute ago, springy said:

I'd suspect the 13A Plug to 16A socket adaptor.

 

springy

I think it is the other way around... at the moment, the cable terminates in a domestic three pin [I am rarely in campsites, but often at sites/homes where I can get domestic supply].  So my adaptor is an extra link to be fitted when using those posts at caravan sites [apparently in contravention of caravan site rules, as I have just learned]

[Tony Brooks]

2 minutes ago, Wittenham said:

 

My mains supply may be a bit outside the norm.  My house has solar panels connected to a Tesla battery which powers the house via an inverter until its empty, then switches back to grid.  However, when that gave me only a red light on the charger, I bypassed it by plugging into an outbuilding that takes its supply from a separate feed, and got the same red eye.

 

 

 

Is that a grid tied inverter? If so, there is a chance that for some weird reason the frequency just might be the problem. As I said, get it checked out.

 

I do not discount what Nick said about frequency, but it seems odd that in effect two power sources can give the same fault.

[Wittenham]

3 minutes ago, nicknorman said:

“Takes its supply from a separate feed” - are you sure this is connected direct to the mains?

I am no expert but is on a separate meter with a separate electricity company supplying it. [and separate bills].  I think that means it is separate?

1 minute ago, Tony Brooks said:

 

Is that a grid tied inverter? If so, there is a chance that for some weird reason the frequency just might be the problem. As I said, get it checked out.

 

I do not discount what Nick said about frequency, but it seems odd that in effect two power sources can give the same fault.

 

I am afraid i do not know the answer to that... i know there was a fair bit of pre-work to be done for SSE [I think, possibly someone else] to validate the whole solar panel set up for when we returned power to the grid.

[Wittenham]

19 minutes ago, springy said:

Do you have any other 240v outlets in the caravan, if so do they work when plugged in at home or is the charger the only 240v appliance ?

If they work then its the charger, if not  its the lead or adaptor.

 

springy

I have just tested this and the 240v sockets in the van do have power.  Chargemaster still showing just a red light.

 

another thought:  the cable is long.... 25 metres maybe?  Is that likely to be a factor?  Note that the same cable [plus a short length of adaptor] worked at a campsite.

[Tracy D'arth]

If the mains plug (wrongly) adaptor works at the caravan site it must be wired correctly but do check it.

 

It comes to the conclusion that the wiring at home is in some way responsible. Is it a "TTC"  or "TT" supply?

 

The inverter could be off frequency.

[David Mack]

15 minutes ago, Tony Brooks said:

Is that a grid tied inverter? If so, there is a chance that for some weird reason the frequency just might be the problem. As I said, get it checked out.

There's no way the OP's solar inverter is going to pull the National Grid off its 50Hz frequency. And if it did, the whole national electricity supply would change, and everyone with a similar Chargemaster across the nation would also get a blinking red light!

Voltage may be too high or two low (with a volt drop in the cables supplying the OP's property), but the frequency will be within the National Grid's pretty tight tolerances.

[MtB]

Just now, David Mack said:

There's no way the OP's solar inverter is going to pull the National Grid off its 50Hz frequency. And if it did, the whole national electricity supply would change, and everyone with a similar Chargemaster across the nation would also get a blinking red light!

Voltage may be too high or two low (with a volt drop in the cables supplying the OP's property), but the frequency will be within the National Grid's pretty tight tolerances.

 

 

My suspicion is that while the solar panels are producing, the Tesla system disconnects from the grid and becomes free to do it's own thing, so would be free to drift off frequency whilst disconnected if it so wished. It only needs to sync with grid frequency before starting to export or import. 

 

I think it's time to take the charger and a battery to a neighbour's or friend's house known to be on a grid supply and try it there. 

[Tracy D'arth]

1 minute ago, MtB said:

 

 

My suspicion is that while the solar panels are producing, the Tesla system disconnects from the grid and becomes free to do it's own thing, so would be free to drift off frequency whilst disconnected if it so wished. It only needs to sync with grid frequency before starting to export or import. 

 

I think it's time to take the charger and a battery to a neighbour's or friend's house known to be on a grid supply and try it there. 

That is how I understood it, the mains is supplied from an inverter off the battery until it is discharged and then it goes to a mains feed.

So it is not grid tied.  Certainly odd and unusual installation.

[Wittenham]

2 minutes ago, MtB said:

 

 

 

 

I think it's time to take the charger and a battery to a neighbour's or friend's house known to be on a grid supply and try it there. 

 

I will do that, thanks, and note that I **think** I have already tried a separate supply from an outbuilding.  I am now wondering if that is in fact separate [but pretty sure it is].

 

one other point I should have added.  There are solar panels on the roof of the van connected to a Chargemaster MPPT.  I am going to turn everything off, whack the fridge on full for a couple hours, then turn the charger back on and see if it comes to life.

1 minute ago, Tracy D'arth said:

That is how I understood it, the mains is supplied from an inverter off the battery until it is discharged and then it goes to a mains feed.

So it is not grid tied.  Certainly odd and unusual installation.

 

I think that is how it is set up.  This is one company  offering it [not the one I used]

 

 

[MtB]

1 minute ago, Wittenham said:

I will do that, thanks, and note that I **think** I have already tried a separate supply from an outbuilding.  I am now wondering if that is in fact separate [but pretty sure it is].

 

Well the element of doubt needs to be completely removed. The art of fault tracing lies in changing "I'm fairly sure that won't be the problem" into "I have proved beyond doubt that isn't the problem".