I have a GP9 with Airwire drop in and a 14.8 volt, 5200 mAh battery. Would it be possible to mu it to another GP9? In other words, use the battery powered, R/C GP9 as a battery car with an Electronic Speed Control (ESC), to run them both. It would be running 4 motors, much the same as the Dash 9.
What modifications would I need to make to each?
If you simply want to use the Airwire in the first GP9 to control the motors on the 1st and 2nd, then you need only isolate the leads going to the motors of the 2nd GP9 and wire them to the motor output of the Airwire in the 1st GP9. There’s only 2 wires running between the locos in that instance. There would be no lights on the 2nd GP9, or you could wire the lights to work off of the motor voltage (just like track power).
If you want to control the lights on the 2nd GP9, that might get a bit trickier, but you could just wire the headlights of both units in parallel as you’re doing the motors. You’ll have the headlights on both units on at the same time, but there are worse things in life. That’s more wires (three or four more) running between each unit. (I’m not familiar with the Airwire drop-in wiring; the G3 has a common + and separate ground returns for each light.
Later,
K
With my battery-r/c trail cars I just run one pair, motor power, and run the lights the same as if track powered. Simple & works fine. I use the Aristo style plug (available from All-Electronics). For USA locos I wire them in after isolating the track pickups. Aristo locos I just plug in and use their track/battery switch.
The only mod you need to make to the lead loco is an MU plug out the rear. Front loco will need either a track/battery switch added, or simply clip and isolate the track pick-up and wire in your power from the lead loco. This WILL NOT give you light control.
Can the Airwire handle that many motors of that size?
David Maynard said:
Can the Airwire handle that many motors of that size?
That’s the next question, isn’t it? I think so, but I’ll have to look at the specks. It will run a Dash 9. The “Drop-in” is a G-3 on a board that will fit into a specific space on various USAT locos, different for each, with plugins for ease of installment. It says right here that it will accept as Plug 'n Play, the latest in Phoenix sound boards, but I haven’t put that to the test, 'cause I’m cheap.
Steve,
I’ve been doing this since Airwire900 days.
With 10amp capacity, I can run 2 GP9s on the same RX with no problems…I’ve also run 3 together, but found it only killed the run time since I had more pulling power than my railroad could handle. My ABA F3 lashup had two powered units and one dummy.
One AW900 will also handle 3 (4 axle) Aristo engines without any issues. To get the higher current I chose to limit voltage to 14.4V (just in case).
This years operating plan for mainline freight on the RCRR is to use Aristo ALCo F units in 3 unit lashups with one RX per set. Also, my RX-equipped GP9 will also host either a GP38 or second GP9 depending on my mood for freight moves.
Rockwall Canyon Jeff said:
Steve,
I’ve been doing this since Airwire900 days.
With 10amp capacity, I can run 2 GP9s on the same RX with no problems…I’ve also run 3 together, but found it only killed the run time since I had more pulling power than my railroad could handle. My ABA F3 lashup had two powered units and one dummy.
One AW900 will also handle 3 (4 axle) Aristo engines without any issues. To get the higher current I chose to limit voltage to 14.4V (just in case).
This years operating plan for mainline freight on the RCRR is to use Aristo ALCo F units in 3 unit lashups with one RX per set. Also, my RX-equipped GP9 will also host either a GP38 or second GP9 depending on my mood for freight moves.
Isn’t this EXACTLY what Airwire does when you set-up a “Consist”?
Gary,
Consist is a great way to run multiple unit lashups (normally). If you have less than 6 engines or so this makes plenty of sense.
If you have over 10 diesels in your roster, there is no need to have an RX in every engine unless you want to control them all individually. If so, you have to buy an RX and battery for each engine and then maintain the batteries indepently. F units are the most logical engines to run off a single RX…who needs independent control of an FB unit?
The single RX GP lashup is nice too. I can run my GP solo, or I can add a second or third unit via corded connection.
This has all the financial advantage of running a high-capacity battery car, with the operation advantages of having your battery onboard the loco.
Rockwall Canyon Jeff said:
Gary,
Consist is a great way to run multiple unit lashups (normally). If you have less than 6 engines or so this makes plenty of sense.
If you have over 10 diesels in your roster, there is no need to have an RX in every engine unless you want to control them all individually. If so, you have to buy an RX and battery for each engine and then maintain the batteries indepently. F units are the most logical engines to run off a single RX…who needs independent control of an FB unit?
The single RX GP lashup is nice too. I can run my GP solo, or I can add a second or third unit via corded connection.
This has all the financial advantage of running a high-capacity battery car, with the operation advantages of having your battery onboard the loco.
I’ve actually done this with steam engines (electric) as a double-header. A Bachmann Connie and a Accucraft C-19! Took a little time to get their speeds matched, but it DOES work nice.
OK, so I’ve found this page written by Paul Norton over on the Ottawa Valley Garden Railway Society (OVGRS) http://ovgrs.org/the-trains/mu-connectors/usa-trains-gp-9/ This shows how to set up the second GP-9 to receive power from the GP-9 with the battery and the Airwire Drop-In.
Now, to figure out where to bring power off the Airwire G-3 Drop-In.
Any Ideas?
Hi Steve,
The drop in unit has two (5amp?) connectors for powering motors. Use one for the onboard loco and the other for “dependent” engines. Eliminate the connector from the MU wire you choose on the drop in board to reduce resistance. On my GP I have an outside connector on each end of the loco. I prefer to use the little red JST connectors between locos, but the black connector supplied for the motor connection is what Aristo uses. I
f you only want one MU connection on the engine, use the surplus connector from the drop in board. While you have the dependent loco apart, you may consider disconnecting the smoke unit to prevent possible overloading.