Battery Problem

[Fay]

Does anyone know, I have my mount attached to a 75ah battery on it's own & it has started flashing. The batteries were charged up after I last used them.


I think I will have to charge tomorrow & take then down the road & have them tested to see if the charge is correct. I hope it lasts until I am finished. The SX did not come on when attached to one of the batteries, it was ok the other night & is ok in the mains. I wonder if the batteries have gone duff? 

[Ian]

there may be a problem with the batteries, but firstly, how long ago did you charge the battery? Batteries lose charge over time, possibly as much as 20% per month. This depends on chemistry, battery health, mechanical design, temperature and so on. Secondly, have you checked the electrolyte level? A leisure battery is a wet cell lead acid battery and the acid level should cover the plates completely. Neither of my leisure batteries are sealed, although my car batteries are. This means it has caps in the top, usually six of them, one per cell, that will allow you to check the level and top up if necessary. Bearing in mind that the acid is sulphuric acid and not good to splash around, unscrew the caps and take a look. You should not see anything plate like sticking out of the acid. If you can see the plates then top each cell up with distilled or de-ionised water. This can be bought from Halfords for exactly this purpose. Don't use tap water, it will kill the battery, particularly here coz the water is very hard.

Finally, batteries have a life in service usually around 5 years, batteries used like we use them do not have a hard life, unless they are left attached permanently to a standard battery charger, rather than a trickle charger. This causes the plates to be covered with an insoluble salt which reduces the ability of the battery to produce current. If the battery is old or has been killed with over-charging then you're best off biting the bullet and replacing it.

Oh, and don't store a lead acid battery in a discharged state, this b*ggers them up too. I would give them a charge, how long depends on the charger, and then try again. Bear in mind, if you have a weedy charger a 75Ah battery could take much more than a few hours to fully charge...

[Mike]

Fay is using car batteries, not leisure batteries.

Fay, what do you mean by 'get them tested' ? I have multimeters that can check for voltage, etc.

[Ian]

most of what I said stands, they might not be sealed though, it's worth checking.

car batteries still suffer from self discharge, over-charging, low electrolyte and old age. And they still might take many hours to charge if you use a low current charger...

Fay, I think you can get car battery testers from halfords, they'll give you a clue as to the battery condition.

[Mike]

If I charge mine I leave them to charge for about 3 days prior to a DSC.

[MarkS]

Fay,

This could also be a cable problem - it has happened to me twice.

First time I picked up the wrong cable - one with thinner wire and greater resistance - this caused the mount LED to flash.
Next time, I used the correct cable but the wire inside was beginning to break up - causing greater resistance and flashing LED.

It could also be a bad connection somewhere else in the chain.  Those mounts draw a lot of current and such things can "tip it over the edge".   Only way to be sure is to switch to a cable you know is OK.

Mark

[Fay]

This is all very interesting.

The mount cable is quite thin. It was ok then started flashing, as it did the other night, it then flashed all night, it then stopped, started flickering, then flashing again. It likes to have it's own battery, where it will be fine, not sure if a thin cable can have some input here, regarding sharing a cigarette connector.

I will check the fluid today. They are on cgarge & I switch them off when the green light changes position & indicates maintaining.

The dew heater goes on the yellow jumpstart. So, I have laptop, mount, 1 or 2 cameras to think about. I was going to charge & go to Halfords so they can test the charge. I have done it before, as I had doubts, & they said it was fully charged.

[JohnP]

Fay - I said I would pop around & have a look for you - offer still stands...! I can bring a DVM & also my battery - that way you can isolate cables etc. I would say that issue is either with your charger or as Mark says connections...

[MarkS]

The EQ6 handset (and probably also the EQ5) has an option under "Info" (I think) to display voltage - this is the voltage actually getting to the mount and is very useful to help diagnose faults.  E.g. if wiggling cables or connections causes the voltage to change then that is a strong indicator of the problem.

Mark

[Fay]

Thanks, that would be great John. I have checked the water in one of the batteries, as the other is charrging & it is ok. The laptop was fine, I am thinking that perhaps the mount cable is too thin. Mark, that is a good tip. I will look into that.

[JohnP]

Well I can bring mine around & you can try with that.... John.

[RobertM]

Could also be that you have a few dry joints or even a few copper strands shorting out.  It's worth checking that all the cables are ok by wiggling them about a bit. 

It's also worth pointing out that you will definitely loose voltage across some of the cables especially if you use something like a 4-way junction box.  I tend to use the cigar lighter junction box for lighter items like the focus/filter wheel and Atik 16ic, plus there is a straight through socket which the mount is connected to.  The other things ( are more directly coupled to the battery by the stabilised PSU I use (SX/dew heater and cigar lighter junction box).

My batteries (85Ah leisure) usually last about 5 sessions of 4-5hrs but that depends on how much slewing I do and how much dew prevention I use.

Hope that helps.
Robert

[Fay]

Thanks Robert. What is a straight through socket?

[RobertM]

On my 4 way socket adaptor I have 3 outputs that are current limited and 1 that isn't.  That one socket that isn't has current limited by the main fuse to the 4 way adaptor (10A is usual).  It's marked on the adaptor (at least the one I use which is this http://www.maplin.co.uk/module.aspx?moduleno=42895).  I believe it's there so you can still plug a cigarette lighter in.

[Fay]

Robert, I have got one of those! It has 4 lids with a white cross thru & one that has not. I assume that is the one the mount should go in