Lister Showman Liberty Liberetto Powerpack Advice

Shear Ease

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www.sheareaseltd.com
This is a shameless copy and paste from a reply I gave someone a few seconds ago. Allow me to be so bold as to suggest it is valuable to any owner of the above machines. Allow me also, if you will, to impart some of the UK's finest advise on getting the very best out of your Lister Powerpack...

It has a charge time of 11-13 hours. The charger is not a 'smart' charger so will keep trying to charge your battery endlessly instead of stop charging when the battery is full. Easiest way to get this right is to plug it in in the evening 11-13 hours before you get up the next day. Unplug it when you get up.

Your battery will keep it's capacity better if you run it completely flat and fully charge it. Don't store it half charged (or fully for that matter) and don't charge it when it's half charged.

Store you battery discharged and charge it overnight the night before clipping. Unplug the handpeice when you store it.

Don't let you battery sit for months without use. They lose capacity when you do this. Charge and discharge it every fortnight or so.

When you have your clipper serviced, send in the charger. Either that or test the charger output yourself. The output should be 12vdc. It should be checked as often chargers develop a fault (I assume a short in the transformer) that results in an output higher than what is needed. Anything output over 15vdc would be considered by me to be faulty and will erode the capacity of the battery. (Could get technical on that but I won't!)

Happy clipping!
 
I always thought cordless might not be as good as them seemed and this thread has just confirmed it! What a faff :o Will stick with my mains ones for sure!!

(Thank you for a very informative thread though!)
 
Woops! Was not my intention to make it sound hard work!

A shortened version could be 'store it flat, run it flat and don't half charge it'.

Batteries should always be considered a 'consumable' item that has a lifespan - you can increase their lifespan by carefully sticking to above (or get even more faffy - won't bore folk with the details though!) but they will eventually lose their capacity to the point where the frustration drives you to get a new battery.
 
Good advice! However my hubby had to put in new batteries last winter for me and despaired over my treatment of the battery so he took over the clipper charging duties - result!
 
I'm sure for many, the positives will far outweigh (what I see as) the negatives but thankfully I am in the lucky position of having electricity and good to clip horses so will stick with what I know.

For people who do own cordless clippers I'm sure this thread will be a huge help in prolonging the battery life of their battery :)
 
Woops! Was not my intention to make it sound hard work!

A shortened version could be 'store it flat, run it flat and don't half charge it'.

Batteries should always be considered a 'consumable' item that has a lifespan - you can increase their lifespan by carefully sticking to above (or get even more faffy - won't bore folk with the details though!) but they will eventually lose their capacity to the point where the frustration drives you to get a new battery.
This makes it sound like Lister is using battery technology from the late 90s. No battery manufactured today should exhibit a memory effect like you've mentioned. http://en.wikipedia.org/wiki/Memory_effect

Can one not purchase just a replacement battery? I would not expect it to be more than £40 and would happily pay that to not have to mess about and worry about charging/discharging and not half charging. :D

From the manual
• Charge using the supplied Lister charger only (15V / 400mA)
• Charge indoors only. The charger must be kept dry at all times
• A new Powerpack must be charged before first use. It will not reach full capacity until it has been fully charged and
discharged 3 times. This means that the clipping time may be reduced for the first 3 times it is used
• Connect the Powerpack to the charger cable and plug the charger into the mains
• A full charge takes between 11 and 13 hours
• Partial charging and discharging will not damage the Powerpack. The energy stored is proportional to the time spent
charging
• Overcharging will not damage the Powerpack, but it should not be left permanently charging when not in use

From another site selling the Lister
The new NiMH battery pack can be topped up at any time because it has no memory effect.

When the battery reaches the end of its lifespan it will lose its capacity. No amount of special charging is going to stop that.
 
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To Sebastian:

NiMh batteries ARE technology from the late 90's.

True 'Memory effect' is a specific problem with nickel–cadmium batteries that never really happens to NiMh batteries. It is actually low voltage problem and not a low capacity problem. All the capacity is available but only at low voltage. The appliance stops working because the voltage is too low, not because there is no charge. Lister are not lying and this does not contradict what I said. They used to have a NiCd battery which has true memory effect. The new NiMh battery does not have true memory effect.

The problems I have described (and please note, 'memory effect' is the label you gave it, not me) are a loss in capacity, not a loss in voltage.

The line:

• A new Powerpack must be charged before first use. It will not reach full capacity until it has been fully charged and
discharged 3 times. This means that the clipping time may be reduced for the first 3 times it is used.

This is the reverse of what you labelled 'memory effect'.

Hope that clears it up.
 
True 'Memory effect' is a specific problem with nickel–cadmium batteries that never really happens to NiMh batteries.
David Linden, Thomas B. Reddy (ed). Handbook Of Batteries 3rd Edition. McGraw-Hill, New York, 2002 ISBN 0-07-135978-8 page 28-18 disagrees :)

NiMh batteries are a technology of the 90s, however, that does not mean that the manufacturing process has not improved since then.

It is actually low voltage problem and not a low capacity problem. All the capacity is available but only at low voltage. The appliance stops working because the voltage is too low, not because there is no charge. Lister are not lying and this does not contradict what I said. They used to have a NiCd battery which has true memory effect. The new NiMh battery does not have true memory effect.
This now sounds like you're talking about voltage depression. Voltage depression is caused by overcharging.

The reason why I mentioned the memory effect is because you said, "Your battery will keep it's capacity better if you run it completely flat and fully charge it. Don't store it half charged (or fully for that matter) and don't charge it when it's half charged."

Memory effect describes the specific situation in which certain NiCd and NiMH batteries gradually lose their maximum energy capacity if they are repeatedly recharged after being only partially discharged. The battery appears to "remember" the smaller capacity

Please don't take offence. My point at the end of the day is that faffing about that much isn't something that people should be putting up with in this day and age when it comes to rechargeable batteries.
 
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No offense taken, nothing I like more in life than to engage in a well thought out exchange, only this way can one increase the accuracy of one's thinking!

In all honesty, it's overnight now and I can't quite work out what our differences of opinion are!

Let's be clear, there is no such thing as memory effect. Batteries do not have memory, they do not remember anything. To most folk who are not interested in the science behind it, every situation where batteries 'appear' to stop lasting as long are bundles together and labelled 'memory effect'.

It is my claim that true memory effect is when for example, half the batteries in a 12v pack no longer produce 12v but say 6v. Once the 12v batteries have released all their mili amps the whole battery pack then drops down to 6v - which is not enough to run the appliance and folk assume the battery is flat. (which it effectively is) In truth though, the pack still has enough mili amps to run the appliance but they are being released a 6v.

It is also my claim that the slow lowering of a battery capacity through non-optimum charging cycles is not true memory effect. This still happens in NiMh batteries and can be avoided by fairly simple routine.

If we cannot reconcile our positions then that's fair enough. You have not convinced me of your position and vise versa. I am happy to carry on the exchange but I do see little purpose as I do not know the science well enough to convince you and I suspect, vise versa also. I suspect we could be going round in circles endlessly with this one!

Your point at the end of the day is that faffing about that much isn't something that people should be putting up with in this day and age when it comes to rechargeable batteries. I agree completely with you. This is why I always recommend a Heineger Xplorer when folk ask about cordless clippers. Lister batteries are old technology. All new cordless appliances should be fitted with Li-Ion batteries and Lister are off the pace with this one.
 
just to say I have lister showman clippers which are approx. 40 years old and am still using the original battery . it is held together with electric tape. the first time I use it in the winter I charge it overnight and then run it for about half an hour, then charge again overnight and it will clip for almost 2 hours...I clip every month and on subsequent clips I just charge overnight and its fine....I don't think that is much faffing for being able to clip without electricity....
 
Bringing up this old thread about charging a Lister battery as mine seems a bit "dead" this year and I certainly haven't even looked at it since last winter let alone had it out to use it charge it or discharge it! So have I killed it?

Out of interest how do you discharge the battery if you're not going to be using clippers throughout the year? I only clip in the winter months? And how many charges/discharges are these batteries up to, or is it endless if you keep doing it religiously?

I charged mine up overnight and only got an hours use out of it.

Whats the little reset button on them does anyone know, what do I use this for? And why is there no light on the battery to tell you when you're charging it? Perhaps my charger is at fault? How can I tell which is bad?

Thanks.
 
Hi,
The easiest way is to leave the clipper running. Take the blade and tension set off and just leave it running somewhere quiet.
I'm not sure how many cycles you should expect from them. These batteries have a lifespan whether you look afetr them or not, looking after them does increase the lifespan but does not make them immortal!
The jury is out about whether or not you can increase the run time of any rechargeable by giving them a few 'full' cycles. Some experts say you can, some say you can't.
The red button on the battery is a ressettable fuse. Should the clipper try to draw too much current (either by a fault or excess stress on the motor with too much tension) the fuse will trip.
There is no light on the charger because it is pre-historic. You can test the battery and charger with a multimeter.
On the charger put the two probes across the two pins that are left and right (the central one is to stop you putting the charger in back to front) Doesn't matter which way round. If you get a minus figure, swap the probes around and this will give you the voltage output. It should be 15vdc. There is no guidance from lister as to at what point you have a problem but we suggest anything above 20% of any charger output will damage your batteries in the long run. Anything less than 12vdc won't be charging your battery correctly. This assumes you have an old charger. A new charger is 'smart' and has lights on it. A new charger output should be 12vdc
The battery is the same but you have the socket instead of the pins. Output should be 12vdc.
Unfortunately it's not possible to quickly tell a batteries capacity, run time is the best way to tell this.
Hope that helps!
 
an update on my 40 ish year old battery.....after all of those years of service it has finally died!!!!!!! I have bought an adaptor as I am now at a yard with electricity and the adaptor was a lot cheaper than a new battery . I didn't want to spend too much as my clippers may die as well soon but I still prefer to use cordless even though my horse is excellent to clip but money dictates....
 
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