Which Power pack/battery to run my EQ6?

[iceman]

Hi all

Just thinking about power in advance of SPSP.. I'm hoping that I can use RB's hotbox to power my laptop, external HD and DMK camera - but not wanting to drain too much power from it, I am looking to power the EQ6 in the traditional way (using a battery/power pack) as opposed to running it off 240v as I am now.

I've got a 17ah jumpstart at the moment that I got from an auto shop a year or two ago, but the charge doesn't seem to last very long these days and the recharger I'm using doesn't always work.

I want/need a 2nd one, so i'm after opinions on what I should get.

What sort of battery should I get to power the EQ6? How long will a full charge last? Where should I get it from and how much will it cost?

I'm not expecting to do a lot of slewing, it will mostly be tracking once it's on the object.

What sort of connector do I need to power the EQ6 from it?

Thanks

[rmcpb]

Mike,

Not my strongest point but there has been a thread (http://www.iceinspace.com.au/forum/showthread.php?t=18654) on powering an EQ6 which suggests that it draws about 2 amps normally with a spike to 3 amps when changing direction.

It looks like you are getting into the world of deep cycle marine batteries (have no idea of the costs but on the Central Coast there has to be lots of places selling them). As for size you need to calculate the number of hours you want between charges by 2 to get the amp/hours then add about half again for a buffer and you are away.

Sooooooooooo say you image for three nights for 10 hours then you would need 30x2=60 amp hour battery plus a bit extra. BUT, as there are recharging facilities out there a 40 amp hour battery would be more that ennough if you don't forget your charger.

Hopefully someone else who has actually used this gear can verify, or shoot down in flames, this "advice" given by someone who has school boy electronics from 35 years ago and who has never used this type of gear :)

[Omaroo]

Theories and amps, draw, milliwatts, sinewaves, etc aside - practical experimentation has yielded to me that my 78AH car battery mounted in a nice box with two of every plug imaginable (2 x merrit, 2 x ciggy, 2 x microphone, 2 x anderson) connected in parallel does the trick just fine for three typical nights of 12" LX200GPS operation. I have a charger for it that lets it trickle charge and maintain the float level correctly. It's a little heavy, but if you stick one in one of those rolling toolbox cases from Bunnings you're laughing. If you go with an AGM (glass mat) version you could even store it in whatever orientation you wish.

[Scorpius]

A good sealed lead acid battery will run an EQ6 all night.
I have had no problems. Using both the Jumpstart Units (900A rating) and individual SLA batteries. Most car shops that sell JS units sell spare 15amp SLA batteries at around $58 which is good value all you need is a regulated 13.8v charger to charge them. keep them on charge when not in use.

DSE Jaycar sells charger packs. You will need one rated at 500Mah (half an amp)
Hauling car batteries is not necessary. I also run a 600w inverter to power my laptop computer on SLA with no problems

One secret Good batteries. Well Charged. Short cables
Remember green to green red to red Other way round and your gear is dead. A series diode in the positive line will prevent errors, but will drop the volts a bit. But a diode at 20 cents is cheap insurance !!

The connector is a 2.1mm DC plug center is positive
The max current drain is less than 2 amps. The specifications calls for a 11 to 15v 2amp source. However in the tracking mode the current drain is quite low. When stating specs. The source of supply is usually twice that needed but capable of the maximum at any time. IE Overload or Obstructed Scope.

For short periods the batts can be charged from your fag lighter in the car driving to the site. This is not recommended for long periods as the car charging level is over 14Volts on most cars

[rogerg]

I'm surprised at the amount of juice you guy's seem to need for the EQ6's.

My Losmandy draws 300mAh, and my 12" LX used to draw about 400mAh I think. Both could run for a couple of nights off a 7Ah battery before I charged it.

:shrug:


These days I use a 40Ah SLA, but that's just so I can get 2 solid nights including laptop with webcam guiding with DSLR ... all running from the one battery.

Best thing I ever did was put a amp metre in-line so I know how much my setup is drawing all the time.

[iceman]

Dave - great info, thanks!

Would it be too much to ask to ask you to go one step further.. that is, list (provide links to) the actual items at (for example) Dick Smith?

That way I can go up to the local DSE with a part list and get exactly what I need.. It sounds like you've got what I need, so your recommendation is very helpful.

If you could include the inverter, that would also be very helpful.

Thanks heaps!

The list would include:
- SLA battery?
- Charger
- Inverter
- Battery->EQ6 cable/pin/plug

Anything else?

[ving]

i use a 17ah and it works well for a nights work...:)

[33South]

I use a 33AH SLA battery, as I only use it for the mount I would expect it to last 2 nights maybe 3.
Although if mains power available I try to top it up each day, usually takes less than an hour - benefit of a regulated 12A charger.

Ill be bringing the charger to SPSP so anyone needing a quick top-up is welcome to hook up.


On the subject of inverters, to run my laptop I dont use an inverter I have a 'thingy' that runs off a battery and ups the voltage to the required and plugs straight into the lappy, seems to work ok.

Any views if this would be more/less efficient than going via an inverter ?

[merlin8r]

You just beat me to it. Save your money and power, just buy the DC to DC converter. Has a ciggy plug on one end, an output voltage selector, and an output jack. A lot more efficient than stepping 12V up to 240, then back down to whatever your laptop uses. I had a sparky test this for me at the Macquarie Uni open night a while back. The inverter used about 4 times the power!
Jaycar part numbers: 2.9 Amp MP-3463
5.0 Amp MP-3467

Clear skies,
Shane

[33South]

Thanks for the confirmation Shane, it seemed logical it would be less drain on the source, and Ive never had an inverter for comparison.
Mind you it dont take long for the laptop to drain a 100aH battery no matter what you use.:(

[iceman]

Problem is, I need more than just the laptop. I also need to power my external USB2 hard drive, and my firewire hub (to power the DMK21Af04).

[Outbackmanyep]

Just beware using cigarette lighter sockets, especially on Japanese vehicles IE: Toyota's, as they use an overheat fuse plug on the rear of the lighter socket.
I'm an auto elec by trade and i have come across this problem with many Toyota and Nissan cig lighter sockets, the cig lighter sockets are only rated to 10A intermittent use, over time the lead heat fuse on the rear of the socket blows, what you'll find is your fuse in the fusebox will be ok but the cig lighter will still not have power, most cases i have come across has been due to continual use of phone chargers in the cig lighter socket, i would steer clear of them and run a separate fused circuit through a 30A plug and socket arrangement, as i use for my handheld spotlights etc, i also run my equipment off them and never had an ounce of trouble.
Anderson plugs are a heavy duty connector and they are used in a lot of industrial and marine applications and are quite reliable also.....
Some people will never have trouble with cig lighter sockets but as rule its only for intermittent use and not designed for phone chargers or accessory outlets.

Hope this prevents any headaches in the field!
Cheers!

[Outbackmanyep]

Makes my film photography that much more less complicated! :)

Cheers! :thumbsup:

[Geoff45]

Any equipment will draw power, so bypassing things like inverters will be more efficient. You should run everything off a decent 12v battery (scope, laptop, camera, dew zapper etc). I run my laptop off a 24AH battery and everything else of a 70AH one. (I've heard that it's best to keep the laptop isolated from the rest of the power sources--don't know how important this is)

[xstream]

Mike, you can borrow the 115AH deep cycle out of the back of the Explorer if you want. As I have another 105AH I can use for the Engel.

But you'll have to carry it out onto the field. :P

[iceman]

I'm a beefcake John, no worries.. :P Or i'll get Mike Sidonio to tuck it under his little finger and carry it for me :)

Thanks, it would be a great help to borrow your battery if I can't use RB's hotbox.

[Scorpius]

Good advice, But my comments re using the Cig Light socket refers only to around an amp** Anyone who plugged in more than a 10amp device would blow the fuse anyway. Assuming the fuses are correct. As for plugging inverters in the socket. Connecting the wires to a cig plug is impossible, Anyone using smaller wire, would obviously not be of sound mind and is asking for trouble. :rofl:
But....then....there are those .... I have been in electronics for over 50 years and seen some mad things people do with electricity.

** My car is not one of those new fangled push button cars. A Toyota, it has a good solid steel pin straight to the cable

I'm calling it a day GN PS will post some pickies of my power boxes tomorrow.

[Scorpius]

Here it is. Not the best of pickies, had to visit the Dr this morning and gave me some jabs and left my hands real bad. The layout is fairly obvious.

1. small switch on left joins both batteries a 12amp and a 7 amp together, to charge in parallel. (13.8v regulated plug pack)
2. Bank of RCA connectors gives 6 X 12v outlets
3. Large switch, Centre Off, switches between 12 or 7 amp battery (fuses behind panel = 10amp)
4. Cig lighter socket 12v output for EQ6 cable
5. Pos N Neg terminal sockets 12V out.

Second Picky The two batteries inside padded with foam The box is large enough to take 2 x 15am SLA batteries. The lid that goes over the batteries makes a nice compartment to get ones meter and cables. The white RCA with short link to a 2.1mm DC connector is the adapter to plug the charger pack into the RCA bank.
Incidently the box was originally one from Target and had a hair dryer and accesories, which now reside in a Red Dot plastic container.

To run the 600 watt inverter I use a 15amp Jump start pack. It has very heavy DC cables and croc clips On the Inverter and Jump start pack.

This setup lasted me all weekend at a Dryandra Astro campout with plenty to spare

As Roger said. His gear only uses a small amount of current and its same for my setup with the EQ6. It should be noted that when a manufacturer quotes "Amps" ie in the EQ6 specs, this does not mean it uses 2amps, but that is the capability of the power source supplied/required to run the unit "safely" with at least 100% tolerance.

In other words dont tow a 2 tonne trailer with a Suzuki Swift!

[acropolite]

Mike, if you're after the longest (total number of cycles) life, a deep cycle battery, as Ron has suggested, is the best. SLA batteries aren't really suited to deep cycle applications, they will perform adequately, but with reduced life expectancy. Battery life is also relative to depth of discharge, the lighter the discharge the greater the number of charge/discharge cycles before the battery is worn out. If you can, run everything directly from batteries as there is at around 10-15% loss running through an inverter.

[Scorpius]

My final comment on SLA batteries. I have always used well known brands (Yuasa) in my RC scale ships and they get really hammered,** never the less most of those batteries are now 5 or more years old and still working well.

The longest living SLA I had was a 2V 4amp, died after 12 years of continuous use..

Depends on what life expectancy you want and how well you look after them. This applies to any type of rechargeable battery

A 4amp SLA can deliver 80 amps surge (6 seconds max). Thats why they use 15amp batts in the Jump starters.They can get hot and should be allowed to rest a few minutes before a second attempt.

** In a 2 X 550 type motor model ship the initial current drain can be over 50 amps (My model of HMS Loch Killisport on my web page) I get about 3 hours sailing from a pair of 6v x 4 amp batteries with individual controllers.

[iceman]

I picked up a 24ah jumpstarter from super cheap auto yesterday, $102.. more expensive than I was expecting. But it will run the EQ6 all weekend.

[Outbackmanyep]

TOYOTAS RULE!!!! :thumbsup:

Cheers! :D

[Outbackmanyep]

Mike, what sort of car do you drive???