If they don't make a point of telling you what battery they're using, then my bet is that it's cheap and nasty.
For the same money, I bought a Calibre battery box (with overload protection, cigarette lighter socket, etc.) and, separately, a good quality AGM 60Ah battery.
Edit:
AGM = Absorbed Glass Mat, which is a deep cycle battery type:
Quote:
Originally Posted by http://www.firststartbatteries.com.au/whyagmbattery.html
10 reasons why you should choose an AGM Battery:
They are totally sealed against leakage and classed as spill proof;
They can be mounted on their side or end to suit space or environment;
They can be mounted inside your car, 4WD, caravan, camper or motor home, truck or marine vessel;
They do not need to be in a sealed box vented to the outside;
Because they have low internal resistance, they can be fully recharged at a lower voltage and accept a larger current (amps);
From a standard car, 4WD or truck alternator they wil recharge quickly in about 2-3 hours. A deep cycle wet cell battery can take 8-12 hours to achieve only 70% to 80% of its potential charge;
They can be discharged much deeper than conventional deep cycle batteries;
Because of their design, AGM batteries can be recharged up to 5 times faster then a regular wet cell battery. AGM batteries are compatible for alarm penels, cars, 4WD, caravan, campers, motorhomes, truck and marine applications;
An AGM battery when left unattended will only discharge at a rate of up to 3% per month and even after 12 months sitting idle can be recharged and put back to a full charge. A normal wet cell battery discharges at a rate of up to 4% per week;
AGM batteries were originally developed for the military. They are designed and built tough, and will take an enormous pounding. They are designed to withstand shock and vibration better than any standard battery.
I have been looking for a new battery alternative, been buying Sonnerscheim GELS up until now, but not happy with overnight performance. I think I'll try this one next:
I use one of these. 150 bucks from jaycar it is a jumpstarter, compressor,has two cigaret lighter sockets, 400W inverter and with LED lights. I use it to run my cameras doing timelapses and dew heaters and easily lasts all night and more. If need can also run my EQ6 but I haven't yet .http://www.jaycar.com.au/productResu...keyform=CAT2#3
I buy deep cycle AGM batteries on Ebay from an online store called Battery-ehome (Irenehang) These batteries are brand new, but over 12 months old. They are a fraction of the new price and perform with no problems
For example: CSB AGM 65Ah for $72.60-pick up from Wetherill Park
AGM 12V 42Ah for $50.00 + $31.25 postage
Last edited by Larryp; 22-02-2013 at 10:04 PM.
Reason: Add examples
I was in Aldi's at Blackburn the other day and they had the 17amp jump start same as Jaycar for $ 79 I was very tempted for that price except I already have one. Works well too.
Might be worth a trip you could buy 2...
Matt
I use a cigarette lighter-to-mains adapter on one of them to power e.g. laptops (with a powerboard).
I have one of the jump starter batteries plugged into the charging port of the other one, and have all the telescope stuff powered by the jump starter that is being charged by the other. (Does that make sense? It doesn't sound sensical in my head but it is late...).
This gives me enough juice to run the following for eight hours (exact time unknown, 8 hrs is the most I have done):
-2 laptops (one for tethered camera control, the other for running Deep Sky Stacker while on-site to save processing at home).
-An iPad
-An iPhone
-A SkyFi WiFi adapter
-HEQ5 Pro mount
-Camera
Additionally, this gives me enough power for the laptop on the way home to do DSS stuff while I'm driving. Also, if I wanted to, I could charge the batteries on the way home via the car battery/cigarette lighter... and hence get even more power. It takes about eight hours to charge one of each of them through mains power.
Unfortunately, the plugs on them aren't that durable. I bought one just after Christmas and the plug itself came out of the casing on first use. I returned it to Supercheap and got a replacement, and that one has been perfectly fine.
I bought a second one about three weeks ago. The plug on that also came out on first use (and I am going to get it replaced this coming Monday); hopefully the second replacement doesn't have issues.
If you're willing to risk getting a dodgy one and that you may have to get a replacement at no additional cost other than your time, then I can definitely recommend these.
Last edited by HunterGeo; 24-02-2013 at 01:33 AM.
Reason: Added charging time and ability to charge through car.
I made my own power caddy. It has a ciggie lighter socket, carries my red light torch, has a lidded compartment for Allen keys, small screwdrivers, fuses and other bits and pieces I may need, plus a recess for a 7Ah extra battery if required. Battery is an 18Ah Agm deep cycle, but it would be easy to make a bigger version to accomodate a larger battery.
Electrics and wiring are not in my expertise range. So Larry yours look great, but beyond me. Dave your 34Ah sounds good, but complicated. At best I can change a light bulb, and wire a plug (with instructions) after that it's confusing.
I suppose I'm looking for the easy way out, one unit that does it all. I have read that a power supply of at least +20Ah for a full night out is the sort of minimum required. I have seen the formula for working that out. I figure with the mount, camera and laptop (laptop for running PHD and the guide camera) all running on a 44Ah supply, it would be more then enough. I would also need a converter for the laptop from 12V to 19v - extra $75 (why can't everything run off 12v?).
I have yet to pop into Supercheap to have a good look at the Calibre, in partricular the battery type and quality.
Supercheap Auto's latest catalogue has Calibre battery box for $49.84, 30% off-starts tomorrow.
Comes with 12v output socket, circuit breaker and external terminals.
Team it with an agm deep cycle battery available cheaply as 12 month old or more stock on Ebay, and you have a good power supply for around $100 or so.
Powering the mount and the laptop - excellent. Everything worked fine.
Added the guide camera (running through the laptop) and low voltage warning/alarm. Turned off guide camera - everything back to normal.
Hoping it was the fact that the power pack battery was not fully re-charged from last session (the trickle feed recharge is very slow) and that the laptop battery was also low and was being charged while working. Laptop was running in normal mode as "eco" mode slows everything down too much.
I'll give it another go when everything is fully charged and see what happens!
It could be excessive drain on the battery which is dropping the voltage. I see the same effect when I use my netbook 12V charger. The voltage comes back up when I switch it off. It can cause mount problems if you have too many items running off the one circuit. I use two seperate 20AHr batteries. One for the mount and the other to power accessories.
Hopefully problem solved. Ran everything this afternoon for over an hour, no issues.
This time had laptop battery fully charged before I started. Seems trying to power all the accesories and recharge the laptop battery was a little too much. Must now remember to ensure laptop is fully charged before I start a session.
I am running active USB cables so will also look at adding a powered USB hub (5v, 500ma), that should also help with spreading the power drain.
Some suggestions Rod.
The power pack that doubles as a car jump starter has enough
power to run several mounts and a dozen laptops for an hour or so. With a full charge
your power pack should run your mount,laptop, and camera for several
evening sessions, unless you are doing a hell of a lot of scope slewing.
I think your
problem was that you were charging the laptop and running a guide camera through a cable with too small a cross section, and therefore
getting a significant amount of voltage drop. I suggest that you
arrange a separate supply to the camera which will prevent you
getting problems during long exposures [which would be very annoying].
hope this helps
raymo
