Need REGULATED power supply for GOTO mount?

[csb (Craig)]

I've just ordered the HEQ5 Pro mount with SkyScan and the guy at Andrews Comm told me that I need to use a regulated power supply - this is to protect the electronics from power spikes.

I had a look in IIS forums and no-one seems concerned about using regulated or not. I noted some do have regulated power (eg PowerTank).

I have a rechargeable JumpStart pack but it doesn't tell me if it's regulated or not - couldn't find that info on the Net or dealers' sites either, so I think it probably is not.

I will get a rechargeable regulated power supply but I don't really want to pay the price of the Celestron PowerTank - >$200.

Anyone have some suggestions.

Also, does anyone ensure that they have a regulated power supply. (I already have a 240v plugin adapter that is regulated).

[[1ponders] (Paul)]

I always use a regulated supply.

Powertech MP-3017 regulated Power supply 12 V 2 amp. $59.00
http://www.andrewscom.com.au/site-co...section-09.htm

I also use a Powertech MP-3079 12 A one but Andrews have a 20 A one (MP3078) for $99 which seems a bargain to me especially seeing as I bought mine from another shop and paid considerably more for it from memory.

[OneOfOne (Trevor)]

The Celestron Power Tank is not "regulated", neither are the jump start batteries. Normally "regulated" would refer to power provided by the 240v mains, if it is not properly regulated any power spikes in the mains may be passed through to the output and onto your scope. Any of the battery supplies should only produce spikes if you had a large motor or other large equipment that is plugged in and turned it on...the transients from the startup may cause a spike. I am sure if you would disconnect your scope if you were about to try to start your car! Silly if you didn't.

[davewaldo]

As far as I know all batteries are regulated. They give a nice stable current.

When someone speaks of a regulated power supply they are usually referring to a 240V AC converter / transformer which will supply 12V of regulated power. Not all of these power supplies are regulated so thats where you need to be careful.

Jaycar sells 12V 3A regulated power supplies quite cheap.

I have a HEQ5 and I've recently purchased a 12V 33ah deep cycle AGM battery which I plan to build a box for. It cost $160 from Battery World. It is a bit expensive but it is a true deep cycle battery and should last many years. AGM batteries are similar to Gel batteries in that they don't leak, but they are less fussy with charging and usually last longer. The problem with ordinary Sealed Lead Acid batteries (like those in power tanks & Jump starters) is that these batteries are made to be used a little at a time and kept on trickle charge. Deep cycling these batteries can cause them to fail within a year or less. If you leave them discharged they can last only months.

So I figured the extra cost was easily worth it rather than having to replace one in the near future.

Hope this helps.

Dave.

[Terry B]

I just use a 12v marine battery with a charger connected to it. The battery acts as a "regulator" and solves the problem of the high drain during slews that cause some regulated supplies to not deliver enough amps.

[g__day (Matthew)]

I use mains regulated for the mount and mains un-regulated for focusers and cameras. I use a UPS to line condition and protect all this gear and reduce noise on the line, and run even serial connections between the hand controller and PC through specialist surge protectors - like the kind petrol stations use to protect bowsers from lightning strikes.

A regulated PSU or transformer is generally only $20 - $30 more than a un-regulated one if you shop around (especially at Jaycar).

[Zuts]

Hi,

If you are away from a mains then a simple jump starter pack or gel battery will do. Get the biggest amp hour one you can find. If you are connected to a mains power supply then get a regulated power supply.

Paul

[Starkler (Geoff)]

A 12A/h or larger gel cell and a charging power supply will give you more than enough capacity for a night, and the flexibility to use your mount anywhere without being tied to a mains outlet.

[seeker372011 (Narayan)]

i have used a jump starter for three years and it works just fine

no regulator needed, DC is clean as people have pointed out

[Kokatha man]

Craig - as someone who spent many years as a tech;much of it with power supplies and lighting/power plants with deep cycle storage/back-up, as well as more conventional (auto etc) lead-acid battery/electrical systems; let me sift the wheat from the (fair amount of) chaff flying around re your requirements!

• Andrews edict is to protect both them and you from claims/liabilities arising from overly-high voltages applied to the HEQ5 Pro (of which I own one) as well as giving you some commonsensical warning/advice.
• As someone has pointed out, voltage regulation in the above context, commonly refers to power supplies that convert (supply) 12 volt DC from 240 volt AC (mains) supply.There are other applications but these do not concern your mount or these matters.
• A re-chargeable battery (and this is most commonly a lead-acid type, whether it be standard/auto, deep-cycle or Gell cell etc) will, when fully charged, maintain a stable output voltage more than sufficient for your needs - unless the mount load, ie current drain (amps) versus battery capacity (amp hours) is incompatible.
• In this situation your battery will discharge very quickly and its' output voltage will drop - not good for the battery or your wants but causing no harm to the mount motors.
• Operating the mount via a battery whilst said battery is "on charge" via a charger can be quite permissible if (a) the battery charger/power supply is a well-regulated type or (b) the charger etc is a trickle charge (low current output) device and your battery has a reasonable capacity. (amp hourage)
• This is because, as one person said, batteries in themselves act as regulating devices for any additional power fed to them via chargers etc.
• Regulator devices (IC chips) can be placed across the battery outlet to supply the mount lead and plug. These are simple, inexpensive and small devices that will provide good protection for the mount. (available at Jaycar etc)
• Also, as someone pointed out; if you are running your mount from the car's battery it would be unwise to start the car (and thus its' charging system) whilst operating the mount for above reasons.
• A "jumpstarter" battery pack of suitable capacity is most probably the most cost effective, convenient device for your needs (I and many others use these units without any problems for said purpose) as it should, if a suitable capacity one is chosen, adequately run the mount for a full night's useage before needing recharging.
• They are easy to cart around, display their terminal voltage and employ a trickle charge accessory that whilst best not used during operation is unlikely to cause problems if one does. They have a light (which I've made a snap-on red acrylic cover for) and a positive tip 12 volt take-off that can be plugged into the HEQ5 Pro (though it's best to use the mounts right angle plug) and also have at the other end of the cable which takes the 12 volt power from the jumpstarter unit, a cigarette type plug that doubles as a charger for the jumpstarter when a car is your only source for recharging it.
• You can also jumpstart your car with them!

Cheers, Darryl.

[Karls48 (Karl)]

• Hi Craig. Daryl (Kokatha man) is correct in his explanations about usage of rechargeable batteries to power your mount. Except this “Regulator devices (IC chips) can be placed across the battery outlet to supply the mount lead and plug. These are simple, inexpensive and small devices that will provide good protection for the mount. (available at Jaycar etc) “
• The common regulator IC from Jacar or DS is LM7812. It will not work in this application, as it needs about 6Volts difference between input and output. Which you simply don’t have on 13.8V battery.
• There are Low Dropout Voltage regulators available that require only about 0.5 Volt difference between input and the output. Still they are not really feasible to use to regulate voltage from 13.8V battery to 12V unless you are going to use very large capacity battery. Problem is that your mount will most likely operate quite happily on 11V from battery without any regulator; but it will shut down at 12.5V of battery voltage with the regulator attached. Therefore considerably shortening the time that the battery cans power the mount.

[csb (Craig)]

Thanks all for your very helpful and informative responses.

Also explains why I couldn't find anything on the Net for 'rechargeable regulated power supply' except 240v packs.

And I have more freedom to choose.

IIS is a fantastic place

Thanks again.

[[1ponders] (Paul)]

We aim to please Craig.

[Garyh]

Hi Craig, if running your setup of 240v why not pick up a ATX pc power supply? plenty of amps (mine maxs at 12amps) in the 12v line to run everything and cheap as well.
Runs everything on my setup with no problems and for $40
cheers Gary

[Kokatha man]

Originally Posted by Karls48

• Hi Craig. Daryl (Kokatha man) is correct in his explanations about usage of rechargeable batteries to power your mount. Except this “Regulator devices (IC chips) can be placed across the battery outlet to supply the mount lead and plug. These are simple, inexpensive and small devices that will provide good protection for the mount. (available at Jaycar etc) “
• The common regulator IC from Jacar or DS is LM7812. It will not work in this application, as it needs about 6Volts difference between input and output. Which you simply don’t have on 13.8V battery.
• There are Low Dropout Voltage regulators available that require only about 0.5 Volt difference between input and the output. Still they are not really feasible to use to regulate voltage from 13.8V battery to 12V unless you are going to use very large capacity battery. Problem is that your mount will most likely operate quite happily on 11V from battery without any regulator; but it will shut down at 12.5V of battery voltage with the regulator attached. Therefore considerably shortening the time that the battery cans power the mount.

Thanks for that Karl - I should mention 2 things here: I haven't used any*, or looked at a Jaycar or any other retail catalogue re VR's for quite some time viz specifics; and the suggestion of using said device was meant to be considered as an adjunct to a poorly regulated charger left across the battery.

*In fact, the last time I used VR's in this sort of situation would have been over 20 years ago! I was faced with an unregulated DC supply - one of the ancient 4-blade Dunlite wind generators, the so-called 750W units, that could wind up to way over 40 odd volts, and that even with 500 aH cells, resulted in nearly 42 volts at the terminals, even under loads.

The user wanted to run his sound system turntable (at the time a quite reasonable one) from a 32V - 240V invertor (square wave, and depending on voltage applied, variable output frequency!) and as the winds rose and abated, his turntable accelerated and slowed down in sync, creating interesting vinyls!

With stuff-all to work with I used the particular VR I had with me across the DC supply and, problem solved - that poor little fella was working at the extremes of its' limitations (or beyond) but when I came through that way again some 3 years later, there it was, still keeping this audiophile's system functioning fine!!!

Cheers, Darryl.

[AstralTraveller (David)]

This discussion is very timely as I'm about to buy a battery/battery pack of some kind.

My first battery pack lasted only a couple of years and I'm not too happy about that. I accept that I didn't treat it well - it was discharged too deep too often, not always kept charged and charged with a cheap charger. So I plan to do things right the second time. I will get ample capacity and use a good trickle charger. The thing that I'm now wondering about is whether an AGM or marine battery is necessary or will a standard gel cell do.

I know in the end it will be a value judgment but I'd like to hear as many points of view and share as many experiences as possible before parting with the $$$.

Oh yes, and I'd like to stir up the ant's nest .

thanks,
David

[Zuts]

Hi,

You can buy a battery 15 amp hour jumper pack these days for around 50 bucks. They arent high quality but if they last two years at that price who cares.

If you double the price you will get a better quality unit but I am not sure at double the price it is worth it. You could buy one cheapy and then another after that one failed, you get at least a years warranty so are guaranteed at least two years from your two cheap packs .........

Thats a buck a week, worst case scenario.

A different slant
Paul

[montewilson (Monte)]

If you have no choice get a battery and follow the advice given which seems to based on plenty of experience.

If you have access to mains get a Jaycar power supply. I use a few of them in my set up and they are great. Get one that will do not only the mount but any other equipment you will add to it later. Consider a 10A.

Also that ATX power supply is a great option but you need the older ATX units for this idea to work the newer ones are a bit more complex and not as easy to use.

[Ian Robinson]

You could consider building your own if handy with a soldering iron and electronics.

Plenty of designs in good textbooks.

You can design one yourself easily enough and get any level of ripple required.

[Bassnut (Fred)]

umm, I had 3 different powertec linear supplies from Jaycar in a row that overheated to hell (2 blew up) at less than the rated current. If you read the fine print, most are for "intermittent testing use" (one was for less than a minite). If you buy one, double or triple the rating you need, then they work well.