Author Topic: Losmandy GM8 dual axis voltage (LiPo battery)  (Read 642 times)

Ryan Chaudhari

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Losmandy GM8 dual axis voltage (LiPo battery)
« on: December 28, 2017, 02:45:51 AM »
Hi there
I'd like to replace my heavy 12V battery with a small LiPo battery. The problem I have is that I find only LiPo batteries with 11.1V or 14.8V. The Gemini system supports voltages of up to 18V but the specs for the dual axis controller speaks only of 12V.
Does anyone know if the dual axis controller supports up to 15V? Or do I need to use a voltage adapter?
Thank you and kind regards
Aurel



laycacdownsell

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #1 on: December 30, 2017, 09:38:41 PM »
I've used my Gemini-2 upwards of 15V (14.5V for me) all the time. It actually likes the higher voltage. On the flip side, my STF8300 actually generates strange errors with the filter wheel if you use more than the proscribed 12V.

foarehortalp

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #2 on: January 04, 2018, 03:47:38 AM »
I have 15 volts connected to my Gemini-II. Yes you can supply up to 18 volts to the system; the Gemini folks do recommend more than 12 volts, just to give some extra headroom.

redsfilrerig

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #3 on: January 05, 2018, 03:16:34 PM »
Quote
I have 15 volts connected to my Gemini-II. Yes you can supply up to 18 volts to the system; the Gemini folks do recommend more than 12 volts, just to give some extra headroom.

That's a really good point to iterate. If you've never called Losmandy with a question give it a shot. I think you'll find they're very responsive. It's one of the best reasons to own their products.

omunsopoo

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #4 on: January 08, 2018, 02:32:31 PM »
What is LiPo? I use LiFePO4 (Lithium Iron Phosphate) batteries with no problems. The are "12V" batteries.

Bryan Sonian

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #5 on: January 08, 2018, 11:40:55 PM »
Aurel,

Losmandy does not supply a 12 volt power supply. The only one they now ship is a 120 volt AC to a 15 volt DC. This is a standard laptop computer PS.

http://store.losmandy.com/acdc

Bill

Jairo Zilinskas

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #6 on: January 10, 2018, 11:39:27 PM »
Lithium Polymer battery - its a regular Lithium ion type battery (Li-Ion) with a liquid electrolyte but in a polymer container. They are not as fire safe as LiFePO4https://en.wikipedia...polymer_battery

My remote rig only uses LiFePO4 (in the UPS boxes) because of the potential fire hazard issues with Li-Ion technology
https://en.wikipedia...osphate_battery

nepaletha

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #7 on: January 11, 2018, 05:43:50 AM »
Oh, I guess we've always just said "lithium polymer" here at work. I thought you meant LiPOsuction or something.

Tyler Cox

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #8 on: January 12, 2018, 02:29:26 AM »
Quote
Hi there
I'd like to replace my heavy 12V battery with a small LiPo battery. The problem I have is that I find only LiPo batteries with 11.1V or 14.8V. The Gemini system supports voltages of up to 18V but the specs for the dual axis controller speaks only of 12V.
Does anyone know if the dual axis controller supports up to 15V? Or do I need to use a voltage adapter?
Thank you and kind regards
Aurel

Since you ask about the dual axis controller specifically, the replies related to Gemini electronics are irrelevant. On the Losmandy web page, the only voltage listed for the dual axis controller is 12 V. I wouldn't exceed that by more than a volt or so without contacting Losmandy. Everything about the two controller families is different, and there may be components within the dual axis controller which cannot withstand higher voltages without damage.

It's not too difficult to construct a linear regulator circuit which would allow operation with a higher input voltage, but it does require some knowledge of electronics. However, since the dual axis controller doesn't draw very much current in operation, you may be better off to go with a smaller gel cell lead acid battery if you want to reduce the weight of your equipment.

 -- MC --

Guy Cleveland

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #9 on: January 12, 2018, 07:06:35 AM »
Quote
Quote

Hi there
I'd like to replace my heavy 12V battery with a small LiPo battery. The problem I have is that I find only LiPo batteries with 11.1V or 14.8V. The Gemini system supports voltages of up to 18V but the specs for the dual axis controller speaks only of 12V.
Does anyone know if the dual axis controller supports up to 15V? Or do I need to use a voltage adapter?
Thank you and kind regards
Aurel

Since you ask about the dual axis controller specifically, the replies related to Gemini electronics are irrelevant. On the Losmandy web page, the only voltage listed for the dual axis controller is 12 V. I wouldn't exceed that by more than a volt or so without contacting Losmandy. Everything about the two controller families is different, and there may be components within the dual axis controller which cannot withstand higher voltages without damage.

It's not too difficult to construct a linear regulator circuit which would allow operation with a higher input voltage, but it does require some knowledge of electronics. However, since the dual axis controller doesn't draw very much current in operation, you may be better off to go with a smaller gel cell lead acid battery if you want to reduce the weight of your equipment.

 -- MC --
OK, so the OP mentions that the Gemini system allows voltages higher than 12V. He then mentions the "dual axis controller" and the listed power requirement is 12V.

So, I was confused, but the dual axis controller is the digital drive system.

So, OP what do you have? The digital drive or the Gemini?

Yes I'd only supply 12 volts to the digital drive system but would bump up the voltage no problem for the Gemini GoTo system.

carmiphypart

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #10 on: January 12, 2018, 08:52:20 AM »
I recently bought this to power my GM-8 (non-Goto). So far, it works great. It is small and I keep it velcro-ed
underneath the control unit.

https://www.amazon.c...0?ie=UTF8&psc=1

Jerry Gilbert

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Re: Losmandy GM8 dual axis voltage (LiPo battery)
« Reply #11 on: January 12, 2018, 09:42:01 AM »
You can also buy a small boost or buck DC-DC converter. My favorite trick: a 5V to 12V boost converter, and an ordinary USB power bank (which is dirt cheap).

The DDS draws a tiny amount of power.

I even powered my Tak EM11 Temma2Jr from a USB power bank using this technique (it did require a USB power bank capable of 2.1A output).