Marine battery for GPU

[BaldEagle]

I have one of these on the way:

 

http://www.aircraftspruce.com/catalog/elpages/plugnjump.php

 

To power up the avionics without running the engine (to learn my Aspen / GNS430, etc.), is it acceptable to hang a marine battery off this?  Spruce, etc., have portable GPUs but they are pricey, and as I only want to power up the avionics I'm guessing I only need something like 12 volt 25 amp power source to feed the panel.  Airplane is a '78 J (14 volt system).  Airplane is tied down (waiting for a hangar to free up) so no power outlet and a portable solution required.

[larryb]

Yes, you can do that. The ground power plug is the way to go. It will guarantee that the aircraft battery is disconnected while using the marine battery.  If you just paralleled the marine and aircraft battery both would share the load.

I would probably wire up a dedicated ground power plug and not use the plug you have with jumper cables. Your solution will work, but the clamps can slip and short pretty easily. 

For those who do have AC power available, I use a supply similar to this for my plane:

https://www.amazon.com/BMOUO-Universal-Regulated-Switching-Computer/dp/B01EWG6YT8/ref=sr_1_19?ie=UTF8&qid=1526941754&sr=8-19&keywords=12v+led+supply

[jonhop]

4 hours ago, BaldEagle said:

waiting for a hangar to free up

Are there none available? If so PM me...

[carusoam]

Many have gone with the batteryminder...

A plug can be brought out to a convenient location to connect to the battery (or two)...

Plus it can charge your battery and condition it too...

Best regards,

-a-

[RobertGary1]

11 hours ago, carusoam said:

Many have gone with the batteryminder...

A plug can be brought out to a convenient location to connect to the battery (or two)...

Plus it can charge your battery and condition it too...

Best regards,

-a-

But a batterrminder probably isn't going to keep up with the demands of a full avionics stacks. Teaching in G1000's we have people learning on the aircraft for more than an hour and don't want the ship battery or the standy battery to draw down.

-Robert