16.8V charger for equalising Trojans?

[Richard10002]

I’m toying with buying a new charger, separate from my Sterling inverter charger which will equalise for 4 hours at 15.6V. The main reason for doing this is so that, if on shore power and something trips, I won’t have an inverter depleting the Batteries.

Assuming I replace my Trojan T105s with another set, and Trojan recommend equalising at about 16.8V every so often, is there a charger that has this facility. If available, I would also like it to not revert to trickle after only an hour, under normal use.

Despite not being a fan of Sterling any more, I liked the look of his Pro Chrge Ultra chargers, with the facility to set a custom charging profile. However, I think the max voltage is about 15.6V, much the same as my existing facility.

im guessing that Victron and Mastervolt offer something that will do what I want, but I can’t find anything with a quick google. Somebody might already have one and be able to point me straight to it

Many thanks.

P.S. The latest Sterling inverter chargers have a facility to set “charger only”, but mine was a year early

 

[dmr]

15.5v should be adequate for equalising Trojans unless you have let them get really badly sulphated, and a whole lot easier. Most electrical stuff on the boat will be ok with 15.5 volts but at 16.8 I am not so sure.

.................Dave

[MtB]

6 hours ago, Richard10002 said:

espite not being a fan of Sterling any more, I liked the look of his Pro Chrge Ultra chargers, with the facility to set a custom charging profile. However, I think the max voltage is about 15.6V, much the same as my existing facility.

 

The custom setting on my pro charge ultra contains a very irritating gotcha. There is a circumstance which crops up from time to time which erases one’s custom settings, and it’s not a five second job to put them back in again. 

I can’t remember what the circumstance is however, other than it is bloody annoying! I’ve posted about it on here before though. 

[WotEver]

35 minutes ago, Mike the Boilerman said:

I can’t remember what the circumstance is however, other than it is bloody annoying! I’ve posted about it on here before though. 

Removal of power source resulting in a factory reset?

[nicknorman]

I doubt you’ll find regulated 12v chargers that go over 16v. 15.5v is plenty most of the time, maybe 16v if the batteries are very cold. If you charge the Trojans properly they will rarely if ever require equalising.

[Phil.]

I don't know if your situation allows it, but I use my solar charge controller to equalise and set it at 16.2 volts.

[OldGoat]

38 minutes ago, nicknorman said:

I doubt you’ll find regulated 12v chargers that go over 16v. 15.5v is plenty most of the time, maybe 16v if the batteries are very cold. If you charge the Trojans properly they will rarely if ever require equalising.

Isn't the whole problem of battery charging/ management / et al all part of the fact that 'most' users are using the wrong type of batteries?

Folks start with simple requirements - then graduate to requiring many of the demands of a land based life - but are unwilling / unable to upgrade their power source to an appropriate type of storage device. Reading through some of the threads where folks specify  their needs, it's clear to me that they need a resilient power source. At the upper end that cannot be satisfied by anything less that full traction batteries. Slightly lower down the expense / resilience  scale are semi traction batteries, but they need some care in management. That's a complete pain for newcomers who want (and why not) a fit and forget regime.

It ain't going to happen.

There's no middle course. Fiddle with the equipment, monitor every day top up regularly, replace the batteries at frequent intervals - it works. However, do people really want to do that?

OR spend a lot more and get it right from the start??

 

   

[Sea Dog]

The Victron IP22 chargers will deliver have a recondition mode which delivers 16.2v in normal and 16.5v in high.

[Richard10002]

10 hours ago, dmr said:

15.5v should be adequate for equalising Trojans unless you have let them get really badly sulphated, and a whole lot easier. Most electrical stuff on the boat will be ok with 15.5 volts but at 16.8 I am not so sure.

.................Dave

My Trojans are badly sulphated. Probably beyond redemption. I’m sure I read somewhere that 16.8V is recommended by Trojan for something.

[Dr Bob]

1 hour ago, Sea Dog said:

The Victron IP22 chargers will deliver have a recondition mode which delivers 16.2v in normal and 16.5v in high.

Yes, on Sea Dog's recommendation, I am just about to get an IP22 to use as a charger and relegate my Victron Combi to Inverter only use (as discussed in a recent thread). The IPP22 Bluesmart looks quite a capable charger and is relatively cheap - and controllable via a mobile phone. Looks good on paper.

[Richard10002]

2 minutes ago, Dr Bob said:

Yes, on Sea Dog's recommendation, I am just about to get an IP22 to use as a charger and relegate my Victron Combi to Inverter only use (as discussed in a recent thread). The IPP22 Bluesmart looks quite a capable charger and is relatively cheap - and controllable via a mobile phone. Looks good on paper.

Looks good, but surprised they only go up to 30A.

[Dr Bob]

8 minutes ago, Richard10002 said:

Looks good, but surprised they only go up to 30A.

Yes, but do you really need more? When I get back to base the alternator has been putting a lot in already. Also possible to wire it so you can still use the combi in an emergency. 

[Richard10002]

10 minutes ago, Dr Bob said:

Yes, but do you really need more? When I get back to base the alternator has been putting a lot in already. Also possible to wire it so you can still use the combi in an emergency. 

I could always use the combo if I wanted to charge at 80A for a while.

[Sea Dog]

3 minutes ago, Richard10002 said:

I could always use the combo if I wanted to charge at 80A for a while.

Or the engine. With a 175a alternator, it doesn't take long til 30a is about as much as the batteries want anyway. I have yet to find a scenario which makes it necessary though. 

[nicknorman]

1 hour ago, Richard10002 said:

My Trojans are badly sulphated. Probably beyond redemption. I’m sure I read somewhere that 16.8V is recommended by Trojan for something.

Trojan seem to be rather inconsistent with their recommended charging voltages, there are a couple of different documents on the web which give different voltages. You should be able to recover recoverable sulphation at 15.5v (summer, or 16v winter). Possibly it might be slightly quicker at 16.8v but I doubt it would make much difference. Certainly I wouldn’t want to subject equipment designed for 12v, to 16.8v, so if you do find a means to get that, make sure everything else is switched off.

Edited December 22, 2017 by nicknorman

[cuthound]

In my experience equalizing at more than 2.67 volts per cell (16.0 v for a 12 volt battery) is counterproductive and results in massive gassing and rapid increases in cell temperature.

For badly sulphated batteries several short equalizing charges of a couole of minutes each often works better than one longer one.

Edited December 23, 2017 by cuthound
Correction 1.67 to 2.67 vpc

[Alan de Enfield]

6 minutes ago, cuthound said:

In my experience equalizing at more than 1.67 volts per cell (16.0 v for a 12 volt battery) is counterproductive and results in massive gassing and rapid increases in cell temperature.

For badly sulphated batteries several short equalizing charges of a couole of minutes each often works better than one longer one.

 

I think I have been working under a misapprehension – I was under the impression that a 12v lead acid battery had 6-cells (maybe the 6 filler caps confused me)

If I was to equalise at 1.67 volts per cell that would only give 10 volts

Confused !

 

[Sea Dog]

22 minutes ago, cuthound said:

In my experience equalizing at more than 1.67 volts per cell (16.0 v for a 12 volt battery) is counterproductive and results in massive gassing and rapid increases in cell temperature.

For badly sulphated batteries several short equalizing charges of a couole of minutes each often works better than one longer one.

A high voltage at a high current current for an excessive length of time would surely be a bad thing. The voltage needs to be high enough to cause rapid gassing though, doesn't it? Isn't that the key to the effect? 

The Victron does (up to) 16.2v (in normal) or 16.5v (in high) at 8% of max current for 1 hour - or when that voltage is reached, whichever ones first. I can't remember the exact figures (Nicknorman will know) for my 8 year old Mastervolt Combi, but it was a bit lower voltage for a bit longer iirc. Previously, I've read of folk repeating the automatic equalisation charge on clever kit like the Mastervolt because they thought it wasn't long enough, and folk equalising manually for quite long periods. It may well have turned out to be that a short burst at a slightly higher voltage may be the better solution: it seems that Victron's latest research and trials have led them to this conclusion.

Edited December 23, 2017 by Sea Dog
Up to

[smileypete]

22 hours ago, Richard10002 said:

I’m toying with buying a new charger, separate from my Sterling inverter charger which will equalise for 4 hours at 15.6V. The main reason for doing this is so that, if on shore power and something trips, I won’t have an inverter depleting the Batteries.

Assuming I replace my Trojan T105s with another set, and Trojan recommend equalising at about 16.8V every so often, is there a charger that has this facility. If available, I would also like it to not revert to trickle after only an hour, under normal use.

Despite not being a fan of Sterling any more, I liked the look of his Pro Chrge Ultra chargers, with the facility to set a custom charging profile. However, I think the max voltage is about 15.6V, much the same as my existing facility.

im guessing that Victron and Mastervolt offer something that will do what I want, but I can’t find anything with a quick google. Somebody might already have one and be able to point me straight to it

Many thanks.

P.S. The latest Sterling inverter chargers have a facility to set “charger only”, but mine was a year early

 

How many Trojans?

Can you arrange things so you can easily isolate and eq half of them while leaving the other half connected?

That would open things up to cheaper and more effective options.

Edited December 23, 2017 by smileypete

[Richard10002]

10 hours ago, Sea Dog said:

Or the engine. With a 175a alternator, it doesn't take long til 30a is about as much as the batteries want anyway. I have yet to find a scenario which makes it necessary though. 

Agreed, but not everyone has a 175A alternator. Mine reaches a max of about 30A... which is fine for a good charge on a day trip, but not so good when idling at the mooring.

 

[cuthound]

13 minutes ago, Alan de Enfield said:

 

I think I have been working under a misapprehension – I was under the impression that a 12v lead acid battery had 6-cells (maybe the 6 filler caps confused me)

If I was to equalise at 1.67 volts per cell that would only give 10 volts

Confused !

 

My typo, should be 2.6vpc.

8 minutes ago, Sea Dog said:

A high voltage at a high current current for an excessive length of time would surely be a bad thing. The voltage needs to be high enough to cause rapid gassing though, doesn't it? Isn't that the key to the effect? 

The Victron does (up to) 16.2v (in normal) or 16.5v (in high) at 8% of max current for 1 hour - or when that voltage is reached, whichever ones first. I can't remember the exact figures (Nicknorman will know) for my 8 year old Mastervolt Combi, but it was a bit lower voltage for a bit longer iirc. Previously, I've read of folk repeating the automatic equalisation charge on clever kit like the Mastervolt because they thought it wasn't long enough, and folk equalising manually for quite long periods. It may well have turned out to be that a short burst at a slightly higher voltage may be the better solution: it seems that Victron's latest research and trials have led them to this conclusion.

No, the gassing plays no part in converting the lead sulphate back to lead. It is the higher voltage that causes the conversion.

[nicknorman]

17 minutes ago, Alan de Enfield said:

 

I think I have been working under a misapprehension – I was under the impression that a 12v lead acid battery had 6-cells (maybe the 6 filler caps confused me)

If I was to equalise at 1.67 volts per cell that would only give 10 volts

Confused !

 

It was a typo, he meant 2.67v.

[smileypete]

If you want something off the shelf, the usual options are a programmable combi or charger, programmable solar controller, or a bench power supply.

I doubt it's impossible to recover the existing Trojans, more like it's highly impractical to do so while using them.

Edited December 23, 2017 by smileypete

[Sea Dog]

1 minute ago, cuthound said:

My typo, should be 2.6vpc.

No, the gassing plays no part in converting the lead sulphate back to lead. It is the higher voltage that causes the conversion.

Ah.  I thought the gassing separated the Lead Sulphate coating from the plates.

[nicknorman]

1 minute ago, Richard10002 said:

Agreed, but not everyone has a 175A alternator. Mine reaches a max of about 30A... which is fine for a good charge on a day trip, but not so good when idling at the mooring.

 

Perhaps you need an alternator upgrade or fixing all those little points of higher resistance in the circuit that drop voltage and thus reduce charge current? I would have though you could have a 70-90A alternator at least, and that should put out 70-90A during the early phase of charging. Or maybe you have a partially defective alternator?