I have a question about Deep Cycle Batteries

Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig

Craig wrote:
Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig
Why not connect your stuff together, and measure the current
consumed?
Then it is simply (80% of AH) / amps measured.
That gives you the hours you can expect to work.
There is a huge difference between AC adapters and laptop load,
so testing is your only option.
Last, buy a reliable battery like NORTHSTAR, which can stand
an occasional 100% dis-charge. Expensive, but worth the money.

On Tue, 24 Jun 2008 02:26:34 +0200, Sjouke Burry wrote:

Craig wrote:
Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig
Why not connect your stuff together, and measure the current
consumed?
Then it is simply (80% of AH) / amps measured.
That gives you the hours you can expect to work.
There is a huge difference between AC adapters and laptop load,
so testing is your only option.
Last, buy a reliable battery like NORTHSTAR, which can stand
an occasional 100% dis-charge. Expensive, but worth the money.

How do I do that?

Craig wrote:
On Tue, 24 Jun 2008 02:26:34 +0200, Sjouke Burry wrote:

Craig wrote:
Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig
Why not connect your stuff together, and measure the current
consumed?
Then it is simply (80% of AH) / amps measured.
That gives you the hours you can expect to work.
There is a huge difference between AC adapters and laptop load,
so testing is your only option.
Last, buy a reliable battery like NORTHSTAR, which can stand
an occasional 100% dis-charge. Expensive, but worth the money.

How do I do that?
With an Ampere meter?

Your set up is simiar to mine. You omitted dew heaters, and thats a
battery drain. Here's what I do. I bought a motorcycle/tractor
battery and put it in a plastic tool box. I mounted a multi outlet
on the top. After a nights use I recharge the battery during day
light hours.






On Jun 23, 7:59�pm, Craig wrote:
Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop �and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig

Craig wrote:
Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig

I use deep cycle marine batteries I buy at BJs club. (like sams club)

I run a Mach1gto mount, a Dell 9300 laptop, dew heaters and an sbig
st2000xm. The laptop is the largest draw - around 70 watts, followed by
the camera. My dewbuster controller is pretty stingy with power.

I run the laptop and the camera off a true sine wave power inverter.
I'm guessing it's about 80% efficient with power.

For a 2 night star party where I don't have the ability to recharge
during the day, I bring a 100ah battery and a 60ah battery.

If I'm not imaging, I can get by with the smaller battery.

If I'm imaging and have daytime AC power, I can get by with the larger
battery.

My power calculations are based on staying up all night, but imaging for
about 6 hours.

I am considering getting an Asus EEE laptop for imaging as I don't
really need the 17" screen, and from what I've read the EEE draws about
1/3 the power of my current laptop.

"Mark S. Holden" wrote:

I run a Mach1gto mount, a Dell 9300 laptop, dew heaters and an sbig
st2000xm. The laptop is the largest draw - around 70 watts,

70 watts?! Holy cow, that's more power than my desktop PC with 2
graphics cards in it...

I am considering getting an Asus EEE laptop for imaging as I don't
really need the 17" screen, and from what I've read the EEE draws about
1/3 the power of my current laptop.

The 7" model draws a maximum of 11 watts (less when wireless is off), and
the LED backlight dims down nicely in the field. Recommended!

On Mon, 23 Jun 2008 16:59:05 -0700, Craig wrote:

Hi All,

I'm heading up to Shingletown Star party this coming weekend and I have a
question about the size/capacity of the battery I'll need. I usually image
where I have access to AC power so this has not been an issue for me
previously.

I have a battery that can power my G-11 with no problem. But I have a Canon
20d that I wanted to use the AC adapter for, as well as Laptop and STV
autoguider.

Now I know my small 35amp/hour Gel Cell is not enough for those, so I need
to know how many amp hours I need to get. Is 55 good enough? 80?

I'll be able to charge the batt. during the day from what I understand, but
night time is the issue.

Any suggestions are appreciated.

Thanks

Craig

Thanks All,

I'll take your advise under consideration. It may be a moot point however.
I may cancel due to all teh fires in the area. I'm not overly fond of
mixing my observing with Ash and smoke. Makes it hard to see and really can
play havoc with the optical coatings.

On Jun 25, 8:53 am, "Tom Jarrett" wrote:
"Mark S. Holden" wrote:

I run a Mach1gto mount, a Dell 9300 laptop, dew heaters and an sbig
st2000xm. The laptop is the largest draw - around 70 watts,

70 watts?! Holy cow, that's more power than my desktop PC with 2
graphics cards in it...
[...]

You might want to check the power requirements of your cards.

Many "common" desktops have 250W power supplies, and when I
was recently looking for a PCIe-x16 graphics card the power
requirements caused me to do a double-take. For example, a
single NVIDIA 8600GT states on the box: "350 Watt power
supply with a minimum of 18 Amps on the +12 Volt rail" --
that's 216 Watts just for a single, non-overclocked GPU card
with its own fan.

"Mark S. Holden" wrote:

I run a Mach1gto mount, a Dell 9300 laptop, dew heaters and an sbig
st2000xm. The laptop is the largest draw - around 70 watts,

"Tom Jarrett" wrote:

70 watts?! Holy cow, that's more power than my desktop PC with 2
graphics cards in it...

wrote:

You might want to check the power requirements of your cards.

Many "common" desktops have 250W power supplies, and when I
was recently looking for a PCIe-x16 graphics card the power
requirements caused me to do a double-take. For example, a
single NVIDIA 8600GT states on the box: "350 Watt power
supply with a minimum of 18 Amps on the +12 Volt rail" --
that's 216 Watts just for a single, non-overclocked GPU card
with its own fan.

My 2 x Matrox G200 PCI cards each use 3.5 watts -- no fan, not
even a heat sink needed. :-)