Porta Power Batteries

[castaway]

Further to the post last week on whether these power pack things are any good , I had the opportunity to try one in "real life situ".... As when I launched Fairweather yesterday she developed flat bat syndrome. Up came the yard manager with a Porta power clipped it on and it spun my Perkins 4108 hard till she fired up (First time in 2 years). He really rates it ..and he knows his stuff. It weighs I guess 12-15 kg and is about 1 ft high by 18ins long...I will be getting one for sure ...Nick

 

[halcyon]

What goes round comes round. Worked on portatable battery power systems boats and caravans in the early 1970's, no demand at the time, system just died.


Brian

 

[castaway]

1st time I came across 1 of these was when my brother picked up 1 in Hong Kong about 5 years back,, and they were just becoming available in UK for about 5 times what he paid.
I just got a friend to get me 1 from Makro for £25.... Its prob not as good as the boat yard one.... but at that price what the hell....

I suppose new solid state electronic stuff just makes these things cheaper and more practical now than in the 70s

Regds Nick

 

[ccscott49]

Basically, they are just a sealed starter battery (red top or equivalent) with a solid state charger, you could probably knock one up in a semi sealed battery box, yourself. But if they are really cheap, why bother?

 

[halcyon]

Nearly up to our 70's spec, main differance was we used two 6 volt batteries. This allowed them to be charged in parallel at 6 volt in a car boot ( using blocking diode ) to 100% capacity, used or mains charged ( built in ) in series at 12 volt


Brian.

 

[andyball]

12-15Kg makes it maybe a 50 or 70AH battery in there: of course it'll work well......but for £25 ? I think not.

 

[robp]

Slight digression on this if I may..
I've been thinking about one of these too. Partly because they have an inflator compressor as an extra. Last week posters mentioned an "LVM" type compressor in a thread on inflating tenders. Question is; is the compressor on these cheap Porta Power units of the "concrete parachute" variety? If so, where can we get the LVM type? Be grateful if anyone knows.

 

[castaway]

When I get home Ill look on the box and see what I got for my squids 25. I just chucked it in the boot and thence the garage. Im pretty sure that its not going to be as good at the one at the yard but to be honest the yard's unit that didnt look like would do much either. I might put the spec on a post and all the electrical expects can tell me what a load of rubbish it is....Regard Nick

 

[JerryHawkins]

Don't bother getting one with a compressor - they are of the low volume high pressure type for car tyres. For dinghy inflation you need low pressure high volume - LVM as suggested.

My porta-power pack was purchased from Machine Mart for just under £50 - well worth it. The type your marina chap had (as has mine) cost about £200 and will probably last longer, but I could replace mine 3 times for that!

Cheers,

Jerry

 

[ccscott49]

Actually four times!

 

[castaway]

Ok Ive just got home and the Porta power box is now in the study....So it says:-

400ah cold crankingpower output
12v 17.5 lead acid sealed maintainace free battery
Naturally is got various buttons plugs and a dial plus of course jump leads. Weight is approx 10kg

So would this ever start a marine diesel? or possibly help a bit?
Great thing is of course that its easy to sling in the dinghy and keep fully charged which is where it realy scores over carrying around a spare straight fwd 12v battery.
I must say it doesnt looks as good as the previously mentioned unit in the Boat yard and that really did prove its self ... Nick

 

[ccscott49]

I think that might be 17.5 amp hours, but 400 amps cranking, should start a little boat diesel, especially if it has decompressor lever(s). by the way, when jumping a totally flat battery, disconnect one battery lead, then put the jump starter leads straight onto the the two leads, then start the engine and reconnect the flat battery, BEFORE disconnecting the jump leads. This will ensure all the power from the jump start battery, goes to the starter and not into the flat battery, if you disconnect the leads before connecting the battery, you will/may damage the alternator. Many times people have tried to jump start engines and only managed to flatten the jump start battery! Believe me it works! I've started all manner of things by this method.

 

[bedouin]

FWIW I would recommend attaching the jumper leads as close as possible to the solenoid/starter motor, rather than anywhere near the flat battery. Saves a lot of voltage drop in the cables.

 

[ccscott49]

Why would there by any more voltage drop in the cables than when they are connected to the battery? They should be of sufficient size to minimise volt drop anyway. But I see your point, it also might be easier to connect the cable to the battery, if the jump lead is on the starter terminal.

 

[bedouin]

There would be no more - but don't forget the PortaPower already has cables attached. If you attached those cables directly to the battery, or to the existing leads where the battery is, you get an additional cable run, which leads to additional voltage drop. At the sort of currents required to start a diesel that can be considerable. It eliminates any connections in the cable path (e.g. battery isolation switches), each of which can add a little resistance = volts lost.

As an added benefit you can then use the existing battery isolation switch to connect/disconnect the flat battery from the circuit as suggested above.

 

[JerryHawkins]

Not if you don't count the first one. What I mean is that I could buy another 3 to replace number one if/when that fails to make a total of 4 !!

Cheers, Jerry

 

[halcyon]

One point to remember that if you connect a charged battery to a flat one, the good one will try to charge the flat one and equalize the charge level. The jump leads should go to the engine sideof the isolater switch, with the switch of.
Remember this also applies if you common up batteries to over come a flat one, unless you have two engines, in which case always start the good one first.


Regards

Brian

 

[PeterGibbs]

Get into Argos and buy a Clarke booster - by far the best solution.

PWG

 

[ccscott49]

Did you know, I have never thought of putting the jump start leads on the isolator switch!!! Thats what comes of having a motor vehicle background! Learnt something else today!! Thanks lads!

 

[andyball]

400Amps cranking?....from a 17.5AH battery : that's really impressive.....Vetus only manage 450Amps from 55AH.

Sounds like very good value indeed.