My elderly 43 pound D34 Optima yellow top C20 55 amp hour battery is failing to hold a charge long enough for an extended observing session with my Obsession 18 classic with SC/AN,?I have a powered ground board on my scope.?At the end of a session AN/SC was not behaving normally, and the battery was under 8V.?
I thought it would be helpful to ask what deep cycle batteries those with a setup similar to mine use (brand and C20 amp hour capacity). I use an AGM battery (Absorbed Glass Mat) as my understanding is that type of battery is better than a lead acid battery for deep discharge, and it is cheaper than a gel battery. An identical replacement battery is around $250.
I just haul my battery out into the field for use, it is not in an enclosure.? I have terminals on the battery which are attached to a fused power cable, then which goes into the ground board. Pro tip: attach your cable permanently to the battery terminals rather than using spring loaded clamps which you attach and detach for each observing session: if you get the polarity wrong be prepared to spend a lot of time replacing fuses. Ask me how I know this!
I thought it might be nice to have a power supply with a built in voltmeter so I could know the battery charge without having to pull out a multimeter. I have seen kits online for battery boxes for batteries that include cigarette style plugs, built in USB outlets and such.? Most are for applications like ice fishing and so use small 7 amp hour batteries, my power needs are likely greater if the scope is slewing through the night and running dewheaters for the secondary mirror, telrad and finderscope.? Does anyone use such an enclosure or built a battery box kit successfully?
I like the fact I can run my scope for at least a few days without recharging with the D34 battery, but the battery is a little awkward to lug long distances as it weight 43 pounds and I carry it with a small strap that crosses the top of the battery. Optima has smaller battery sizes such as D35 which has 48 amp hours and weighs 36 pounds, or D51R which has 38 amp hours and weighs 26 pounds.
What battery size do those of you with SC/AN and multiple dewheaters use?
Does anyone use a heavy battery mounted to a cart for easier transport?
I mainly use the scope to home, where there is a power source available.
Thanks!
Greg
I enjoy the capacity of the 55 AH battery, but it is a b
