Need REGULATED power supply for GOTO mount?

[Kokatha man]

And no - this powerpack chareger unit would in all probability be a basic trickle charger (unregulated and unfiltered) that would not be able to deliver the current required! (500mA = 0.5 Amp)

[Fox]

Originally Posted by Kokatha man

Holy mackerel Fox - jist read dis flamin thread, or any of half a dozen contemporary/recent ones on IIS re power supplies.

Not to be too rude though; go to a flamin auto shop and get one of their jumpstart "powerpacks" - get one of at least 17Ah (preferably greater capacity) and choose a dandy little coloured number that tickles your fancy!!!!!

Cheers, Darryl.

Hi Kokatha, Shane...
well, I have actually measured my amps as I remembered I had old car amp/volt/ohm/timing analyser meter. The LXD75 mount only draws 0.5 even at max slewing, but the 3inch Kendrick dew heater draws 1 amp by itself! Anyway, no wonder 7Ah ain't cutting it.

There is a "MotorPro 5 in 1" jumper station at Kmart on special for $99 (I am pretty sure its 18Ah although it's not written anywhere on the box or inside), has two 12V cig outlets, and it looks much prettier than the $99 Projecta equivalent. I am tempted to get the MotorPro, although for only $65 I can get a plain 18Ah SL acid battery from Jaycar...

Can you usually open up (without tearing apart all that plastic) these jumper stations to change the SLA battery yourself if needed?

Cheers
Fox

[Kokatha man]

Hi Fox - if you go that way I can't see why you'd feel the need to "open it up to charge it some other way."

All the auto ones Ive looked at have a mains trickle charger, and a cigarette plug unit that allows you to charge from your car when in a remote location.

This car charger also double as a 12 volt take off to power equipment: the tip polarity is important to consider - for the HEQ5 Pro this plug is the correct polarity and will plug directly into the mount socket; I don't use it because the mount's own plug is just as useable with the jumstarter unit and has a 90 degree fitting.

Just check the Meade's needs and get one as said: at least 17Ah but from my experience the next size up (24Ah?) covers more possibities. To me they are more portable/easy than a plain battery, as well as having a few more features.

Cheers, Darryl.

[Fox]

Originally Posted by Kokatha man

Hi Fox - if you go that way I can't see why you'd feel the need to "open it up to charge it some other way."

All the auto ones Ive looked at have a mains trickle charger, and a cigarette plug unit that allows you to charge from your car when in a remote location.

This car charger also double as a 12 volt take off to power equipment: the tip polarity is important to consider - for the HEQ5 Pro this plug is the correct polarity and will plug directly into the mount socket; I don't use it because the mount's own plug is just as useable with the jumstarter unit and has a 90 degree fitting.

Just check the Meade's needs and get one as said: at least 17Ah but from my experience the next size up (24Ah?) covers more possibities. To me they are more portable/easy than a plain battery, as well as having a few more features.

Cheers, Darryl.

Thanks Kokatha! My power requirements are meagre really, I'm not that big into equipment: an LXD75 for my Genesis and now a dew heater added, that's all. I agree the all-in-one jumper with handle and built-in features is much more convenient than lugging around a battery brick.

Sorry, I did not make myself very clear at all - the reason I ask about opening up the case is that eventually the battery will go, albeit say in 5 years or so if I look after it. So, are these jumper power stations generally user-serviceable wrt to changing the SLA battery if required? (maybe making a mountain out of a molehill, I know, heck what do you expect for a $100 'chinese clone plastic-entombed' battery...!) Fox

[Kokatha man]

Nah Fox - that about sums these things up! The cost of replacement with a complete new unit is nearly allways cheaper than trying to salvage parts.

The main thing to remember in order to maximize the life of these SLA units is to not drain the battery too much between charges: this is why it is better getting one with significantly greater capacity than you actually need (as in amp-hours, Ah, or as is sometimes stated on auto jumpstarters "900 amps" or "1200 amps" - being, I presume, the CCA rating: "cranking amp capacity".)

Having this greater capacity means the battery isn't normally discharged so much over the course of (say) 1 night's obbing; but it is still best practice to recharge the unit after every full night's useage; or to at least put it on charge (with its' trickle charger) once a week/fortnight.

This is because these types of batteries much prefer to "float" near the fully-charged state rather than be "deep-cycled" for maximum life/performance.

Five years might be at the optomistic end of life for an SLA regularly used; but it is possible, and I know of several that have been looked after as above that are 3 plus years old and still performing.

Cheers, Darryl.

[Fox]

Thanks for all the info Kokatha. One last thing I will check on the 5 in 1 MotorPro jumper is that it definitely has a floating trickle charger; from web-research I've done on identical (but rebranded) versions, it sounds that once charged you must disconnect to avoid over-charging (ie. no trickle charge function) - otherwise I will just get an SLA battery and use my own 12V (Powertech) trickle unit.

[Kokatha man]

Originally Posted by Fox

Thanks for all the info Kokatha. One last thing I will check on the 5 in 1 MotorPro jumper is that it definitely has a floating trickle charger; from web-research I've done on identical (but rebranded) versions, it sounds that once charged you must disconnect to avoid over-charging (ie. no trickle charge function) - otherwise I will just get an SLA battery and use my own 12V (Powertech) trickle unit.

Fox - "floating" refers to having a battery at or near fully charged constantly: but in these devices I am certainly not advocating keeping the unit constantly on the unit's trickle charger! All these units have trickle chargers, but these batteries cannot stand this constant charging treatment - I am just advising you to top-up/recharge after use; but then only till the "fully charged" indicator goes on.....

Trickle charging is often used to describe a charger that only delivers a small/low current output relative to the batteries capacity, and whilst some are left on constantly this is not to be done with these babies: apart from cooking the SLA inside, you would get voltage regulation issues with your mount's motors/circuitry!

Cheers, Darryl.

[Fox]

Thanks for clarifying my mis-termilogy and misinterpretations, again!

The Powertech charger I have says that it automatically switches over to trickle charging (its LED flashes when this occurs) when the battery is fully charged - which sounds good I guess. Are you saying that even the 5 in 1 MotorPro power station will likely be the same as well? (I have yet to suss out the "English" instruction sheet included in a MotorPro box, not that I'm expecting a well of enlightening information from such....!)

[Kokatha man]

Fox - what I'm saying is that the auto mart "jumpstarter/powerpacks" have a trickle charger that is used to recharge the battery after use. It is not intended to be left on (ie charging) whilst you are using the powerpack for 3 reasons:

(1) it kinda defeats the purpose of these devices - it's intended to power 12 volt devices (in our cases scope mounts etc) in remote locations or where the use of a mains powered, regulated 12 volt DC supplies are inconvenient, or unavailable, or just not desired for whatever reasons etc.

(2) trickle chargers can still over-charge the (relatively) small SLA's in powerpacks and therefore the battery could be cooked (ie ***ed) if it is left on once the battery is fully charged.

(3) besides the above, once the battery inside the device (ie the SLA) is fully charged; leaving the trickle charger on could easily cause the terminal/output voltage of the powerpack to be too high for the safe operation of the mount and its' internal circuitry etc - resulting in potential *%#@*! to said mount.

I have no specific knowledge about your Powertech charger unit (I presume it is a battery charger!): if it is a regulated output charger system that switches/reduces to a trickle (low current) charge when the battery being charged reaches fully charged (by sensing the voltage) one would need to know at what terminal voltage this occurs. 12 volt batteries' terminal voltages can rise to as high as 15.6 volts when fully charged with some chargers (2.6 volts per cell: (6 x 2.6 volts = 15.6) Whatever its' suitability is for the intended task, point (1) above still applies and depending on what I have just said, also (possibly) points (2) & (3)

Cheers, Darryl.

[Zuts]

It's quite simple really

(1) Charge the battery with the supplied charger.
(2) Plug it into the mount for a nights viewing pleasure.
(3) Do not leave the battery connected to the mains while viewing.
(4) After viewing, plug it into the mains for an overnight topup.
(5) if you dont use the battery for a week see (4)

Paul

[Kokatha man]

Originally Posted by Zuts

It's quite simple really

(1) Charge the battery with the supplied charger.
(2) Plug it into the mount for a nights viewing pleasure.
(3) Do not leave the battery connected to the mains while viewing.
(4) After viewing, plug it into the mains for an overnight topup.
(5) if you dont use the battery for a week see (4)
Paul

Sure Zuts, but Fox doesn't want the abridged version! Besides, it helps keep up my keyboard skills; as well as finding out just how many ways I can describe to him the skinning of a cat.....

[Zuts]

Originally Posted by Kokatha man

Sure Zuts, but Fox doesn't want the abridged version! Besides, it helps keep up my keyboard skills; as well as finding out just how many ways I can describe to him the skinning of a cat.....

Sorry, I just couldn't help myself,.........

Paul

[Fox]

Thanks for all that, yes, I understand to only charge after use, which I have always done. Although I did not understand the potential for still cooking the battery if left on trickle charge for too prolonged times. Fox!

[shane shaw]

Have a new power supply for the lx 200 now. I haven’t tried it as yet because we haven’t had good weather but I am told by a reliable sourse this will work fine to connect to the mains

TARGUS
75W AC POWER NOTEBOOK ADAPTOR
AC INPUT 100-240 V 50-60HZ
DC OUTPUT 15V 5A UP TO 75 WATTS CONTINOUS


Anyone used this ?


Could not get hold of the 18v setup but a friend has advised em he has used this with his lx200 and had no probs.

Am I right in assuming that as long as you don exceede the voltage of the unit 18v that being under is no probs as long as it supplys the right amount of amps.

thanks

[Fox]

Well after all this debate, I think I have turned 180 deg and will just go for a 18AH SLA battery; the MotorPro has lots of gadgetry, but it’s quite big and heavy to boot, whereas I can put an 18AH SLA into a cooler bag.

On another note, I saw some very interesting figures on Volts vs. ‘charge’ with all those 12V SLA EXIDE batts in Kmart:

11.70 V ~ 0%
12.05 V ~ 25%
12.40 V ~ 50%
12.75 V ~ 75%
13.10 V ~ 100%

I really didn’t know that these small differences in volt values on these type of batteries are apparently quite significant. Fox