Ground power
Just bought a 182 with a full Garmin G3X Touch panel, among other goodies. I’d like to find a ground power unit to power the electronics on the ground to practice with the new equipment. Does anyone know of a less than expensive one? Are there any that plug into a wall socket as well as have a battery? My knowledge of these things is very limited.
Thanks.
1976 182P
Comments
I use an inexpensive 'smart' 20 amp charger, set to the AGM battery setting. [ Amazon ]. It detects a 12 volt or 24 volt battery. It works great to run the avionics on the ground, and will not over charge the battery.
Thanks. I’ll look for one. Do you have a brand name?
There are a number of them available on amazon.
this is the one I use.
https://www.amazon.com/dp/B082G1N2T7?ref=ppx_yo2ov_dt_b_fed_asin_title
I have a 1976 182P. I use this 12v external power unit. The external power plug door uses a slightly rounded flat head screw driver. https://www.aircraftspruce.com/catalog/elpages/portPowerCharger.php. I have a separate trickle charger for my battery even though this could charge the battery.
I've used 2 12V 35AH sealed lead acid batteries in series with good success. They're recharged individually with wall wart 12V trickle chargers. Connection for Cessna: https://www.aircraftspruce.com/catalog/elpages/jumperplug.php
I believe that you meant connecting the 12 batteries in parallel, Plus to plus, minus to minus. 24 volts will destroy some of the avionics.!
Either of the units described above can charge the a/c battery using a separate cable with clips directly to the battery.
The 'ground power plug' is not connected to the a/c battery.
RChandra and JimH (third sentence) are referring to the Ground Service Plug Receptacle.
From our 1965 182H Owner’s Manual:
"A ground service plug receptacle may be installed to permit the use of an external power source for cold weather starting and during lengthy maintenance work on the electrical system. Before connecting a generator type external power source, it is important that the master switch be turned on. This will enable the battery to absorb transient voltages which otherwise might damage the semiconductors present in the electronic equipment. When using a battery type external power source, the master switch should be turned off to prevent an unnecessary power drain from the power source to the airplane’s battery.
IMPORTANT Be certain that the polarity of any external power source or batteries is correct (positive to positive and negative to negative). A polarity reversal will result in immediate damage to semiconductors in the airplane’s electronic equipment."
So what does all this mean? It means it’s not like a jumper cable in the automotive sense, but can be used as one. Essentially, it’s stating that the receptacle is connected directly to the main bus and not the airplane battery. Using the cables to connect an external battery – like your car – to the plane will provide power to the main bus. As such, once connected you will hear any unswitched (beyond the master) electrical items, such as the gyros, start up. Connecting the power cable to an external battery is just like turning on the master switch, and all electrical items can be used. With the battery master switch off there is power to the starter key switch, and the external battery alone could be used to start the engine. Turning on the main battery switch will connect the airplane battery to the bus, and then your power supply would begin to charge the airplane battery.
"a generator type external power supply" would be a battery charger or such, and if you're going to use that you should turn ON the master switch before connecting the charger to protect your G3X from voltage spikes, and keep it on for as long as it's connected.
Note that the info you site is from 1965, when battery chargers had no electronics in them and could pass through any voltage spikes on the 120 vac main.
Modern electronically controlled battery charges have sophisticated circuits to prevent any spikes and can be set to a number of battery charging protocols.
No need to turn on the master and connect the aircraft battery, unless it needs charging.