Hi, I'm considering using a 12 volt battery to power my STX-16803 with FW5 filter wheel. Looking at the pin diagram for the power supply there are three +12 volt pins and three return pins. Could you please explain why SBIG chose to have 3 pins at the same voltage? Do I have to isolate all three circuits for some reason? Also, could you please suggest a rechargeable battery that will power the STX-16803 and FW5 for 10 hours? Thank you!
More pins = More currently handling ability. The cooler and motors draw quite a bit of power, and to handle the number of amps needed, you need thicker wire gauge and more robust connectors.
Colin is correct. In order to get a smallish connector to carry that amount of current, we have to use multiple pins. If you use just one pin, the connector will likely be damaged at full cooler power. Both power and ground need multiple pins. They do not need to be isolated, but if you use a single pair of wires they will need to be large gauge. The camera requires 12V at a maximum of 10A. You need a battery capable of at least 100 amp-hours. One example would be https://www.solar-electric.com/unba100amagm.html I would suggest vising a battery store and see what they have. Bear in mind that the voltage will be drooping by the time you hit the full 100 amp-hours, so you may actually need more capacity. On the other hand the current rating is conservative and if you are not running at full cooler power it will not take quite as much current.
Colin and Doug, thank you! One last question - what gauge wire would you recommend if the length is kept under 15 feet?
You want to minimize voltage drop. I'd use 12 gauge. One pair would give you a voltage drop of 0.48V. Three pairs would reduce that to 0.16V. Here's a handy voltage drop calculator: http://www.calculator.net/voltage-drop-calculator.html
Yep, 12AWG is what you want. From a battery perspective, I have 500+ Ah on tap at my backyard observatory. And it never seems to be enough ;-)
Do you plan to have a 12v DC battery cable that works with STXL? The ones listed in Accessories specifically says it does not work with STX/STXL.
We have no plans for a DC cable at this time. You can either buy an extension cable and cut off one end, or build your own. If you want to build your own, here is the connector you need: https://www.digikey.com/products/en?keywords=CP-1060-ND
Hi Doug Thanks for picking up the thread. I power everything off regulated Anderson power pole on my rig. Helps me have exactly one cable going up to my mount(!). Can I use one lead from my distribution box that's sitting on my scope to power this? I actually just bought the STXL16200. So this question is more for that camera. V
You can use one pair of wires, as long as: a) It's a substantial, large gauge pair b) Both ground and power connect to all three pins on the camera's connector. If you don't do that you will exceed the power rating of the camera's connector. Doug
And in case of the STXL16200 it's a 4 pin connection, right? The manual shows a 6 pin but the accessories on the site call out a new 4 pin cable. I haven't received the camera yet. V
It's 6 pins on the camera, but the power supply has a four pin cable. The extension cable adapts between the two. We use a different connector because the other style is better as an in-line type. No one makes high power supplies with long cables anymore because of the Energy Star regulations.
