Old 18-03-2018, 10:58 AM
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nobby2 (Neil)
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Location: Norah Head, Central Coast, NSW
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Is this battery suitable?

After less than an hour use my RA stops working. My voltage gauge tells me about 8v despite starting fully charged at 11.9 v.
Is it normal for the RA to stop while the Dec keeps working with power issues?
I have attached the specs:
DM 12-18 (12v 18AH/20HR)
Sealed rechargeable battery
Constant voltage charge
Cycle use: 14.4 - 15 ov
Standby use: 13.5 - 13.8 v
Initial current: less than 5.4

When I attach my HEQ5 pro mount directly to the power its back to normal operation.

Purchased at JayCar
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Old 18-03-2018, 11:12 AM
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redbeard (Damien)
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HI Nobby2,

If the battery fully charged is 11.9 volts, then it is faulty to start with. It should be at the very least reading over 12 volts.

When SLA battery's get to 9 volts, they are unusable. Never let a SLA battery go below 12 volts.

I'd take it back to Jaycar.


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Old 18-03-2018, 02:12 PM
markas (Mark)
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I've had one of these 12V 18Ah fail like this - definitely unusable.

I put it down to having accidentally charged it at too high a rate. According to the info on my charger it should be charged at 2 amps max.

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Old 18-03-2018, 04:58 PM
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Never drop past 12 vlts and charge at max of 10% of capacity of battery...
Estimate what you need and buy battery that drains only 15% if you use that amount.
It is best to get bigger than less as best policy with rechargable lead acid batteries and to under use it. And out in the cold is not good for a battery.
And dont leave it sitting on a cold floor when not in use.
Keep it clean particularly the surface between terminals...mmm yes all over ..put your multi meter on a terminal and on the surface of the battery and you may get a surprise at the reading when dirty.
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Old 18-03-2018, 05:06 PM
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My figure of 15% drain seems very conservative as we tend to think 25%..as it may be in a perfect world...15% on a cold night is all I like.
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Old 18-03-2018, 05:12 PM
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You can get a deep cycle battery. Then you will be able to drain it safely more than 15%-25% that Alex mentioned.
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Old 18-03-2018, 05:36 PM
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Merlin66 (Ken)
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I have two “golf buggy” 20aH gel cell batteries which I bought back in 2007. I have a triple stage charger....
These are still as good as the day they were bought.
Never any issues with the HEQ5.....
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Old 18-03-2018, 05:41 PM
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Marke (Mark)
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You need to be using a deep cycle whether it's an AGM or Gel they are built to go below 50% better one even lower and will survive just fine that's what they see designed to do.
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