Jump starter packs

Rhino1980 (Ryan) · #1 11-07-2009, 07:48 AM

Hi guys,
could anyone tell me if those 17aH jump packs from supercrap auto are regulated? Or if they aren't is there a way to add a regulator for use with an EQ-6? Or, is it just totally unneccessary?
Cheers

IvanTheTerrible · #2 11-07-2009, 10:49 PM

They are 1 or 2 SLA batteries in a box. So they are as regulated as a battery can be.

Rhino1980 (Ryan) · #3 11-07-2009, 11:09 PM

Thanks mate.

AdrianF (Adrian) · #4 13-07-2009, 02:55 PM

I may have a faulty one but my SuperCheap 17Ah jump pack wont hold a charge for more than 2 hours. Used mine last night to power my EQ6 and couldnt understand why all my photos came out like the scope was jumping around all the pix was blurry and elongated. Changed over to a 40Amp swith mode and everything came good. Checked the voltage on the jump pack and it was down to 9volts. Put the battery on charge over night removed charger this am and the battery was still at 9 volts. Will check the charger tonight.

Adrian

lacad01 (Adam) · #5 13-07-2009, 04:15 PM

I've never used one of those jump-start packs but think you'd be better off spending a bit more money and buying a decent size deep cycle (~75AH min) in a battery box. Not that difficult to mount a couple of 12v cig adaptors, anyhow just my 2 cents

Inmykombi (Geoff) · #6 13-07-2009, 07:58 PM

I have a few of those jump-starter packs ( red ones ) and I use them to power my LX200.

I have never had any troubles with them.
I actually mark one of them to only use with the scope to power the drives etc, and the others I use for dew heaters and a hair dryer when necessary.

Cheap-as and OK in my book.

AdrianF (Adrian) · #7 13-07-2009, 09:06 PM

Mine will probably be ok if the charger had been working properly. No load volts are 14.8 load volts (battery) 6.1 V and doesn't change over time. I have a multivolt power pack I bought for a camera output 1.5A at 15V works and is currently charging the battery OK.

Adrian

Sandrosen (Tait) · #8 13-07-2009, 11:15 PM

Quote:

Originally Posted by AdrianF

I may have a faulty one but my SuperCheap 17Ah jump pack wont hold a charge for more than 2 hours. Used mine last night to power my EQ6 and couldnt understand why all my photos came out like the scope was jumping around all the pix was blurry and elongated. Changed over to a 40Amp swith mode and everything came good. Checked the voltage on the jump pack and it was down to 9volts. Put the battery on charge over night removed charger this am and the battery was still at 9 volts. Will check the charger tonight.

Adrian

Adrian,

If your 12v battery pack is reading at 9v then it could be that the battery is damaged and may not charge back to 12v. Normal sealed and unsealed lead acid batteries have a discharge voltage of around 11v (not capable of handling a load). Below this level and its time to replace the battery, as it has passed its discharge voltage.

DavidU (Dave) · #9 13-07-2009, 11:49 PM

Batterys are non regulated but at full charge give a very smooth 12V in this case.
A regulator like an LM 7812 is a 3 legged TO220 device (looks like a drive transistor) will "regulate" any higher voltage (within certain current draw perameters) to, in this case 12V up to the devices current limitations (in the case of the LM 7812) 1.2A.
So, feed a 12V regulator 14v it gives 12. Give it 16v it will deliver 12V (up to 1.2A) in this example.Give it 10V it aint going to give 12v.
So a battery starter pack is not going to have a 40A regulator.
Most modern astro steppers/ cameras/ drives etc are as I see are designed for FULLY regulated DC supplys. Once a fed device is BELOW it's rated voltage you will get all sorts of faults/anomalies.
However ! Some astro devices have there own regulators.
Please read the little spec sheet that comes with your expensive equipment, it may say..... 12-14V DC 500MA ( this device may well have an internal regulator)
If it says.... 12V fully regulated supply needed. well that says it all.
I have seen thousands and thousands of $ damage by end users not using the correct power supply's.

AdrianF (Adrian) · #10 14-07-2009, 09:05 AM

Bttery all good this morning It looks like the charger that came with the Battery Pak as kicked the bucket. Checked the output volts again on the charger 14.5 V no load 6V with a light load. Have thrown it over the verandah in the general direction of the Green filing cabinet on wheels. Will buy a new charger today and probably a regulated 13.8 V 10A power supply today.

Adrian