Large Scale Central

GP40 + RCS PnP-3 + batteries

The new RCS/EVO PnP-3 Plug’n’Play 3 amp R/C controller was originally designed for the Bachmann K-27. As the PnP socket in the K-27 was based on the existing AristoCraft (AC) PnP socket it means the RCS PnP-3 will fit the AC socket. Whilst the Bachmann socket wiring is back to front when compared to the AC socket, and, the controller dimension specifications are a bit bigger, LS’ers will be pleased to know that the RCS PnP-3 is direct plug in fit into various AC locos. The RCS PnP-3 has self limiting overload protection up to 3 amps at 15 volts, 45 va. Therefore it is suitable for the smaller AC locos without any special cooling needed. The RCS PnP-3 may also be capable of powering the larger locos such as the E8, SD-45 and Dash 9 with suitable fan cooling. Unfortunately RCS cannot give a blanket approval for the entire range of AC locos because of the discrepancies in the wiring between various AC locos. Therefore RCS will give approval as each AC loco has a successful installation completed. There will be a pdf file available at the RCS website detailing which locos have been tested and what, if any, special wiring provisions need to be made. The first AC loco tackled has been the GP40. Here is how RCS did it. Most of the pictures are self explanatory. You will require: 1 x RCS # PnP-3 1 x RCS # BIK-U3 installation kit. 1 x RCS # Y-CABLE to put two batteries in series. 2 x 7.2 volt 2400 mah Sub C NiCd packs. If you don’t already have an RCS TX-4 or TX-24 transmitter handpiece you will need one or the other. After removing the body shell it will be necessary to make a very simple change to the one AC 3 way plug that goes to the socket pcb.

Remove the 2 way plug and bend the wires snugly at 90º.

Then reinsert the 3 way plug and put another 90º bend so the wires sit against the body. This will permit the RCS PnP-3 to sit down snugly in the sockets.

The next step is to remove the fuel tank which is held in by two moulded hooks that can be easily spread to allow tank removal. Once the tank is off remove both lead weights.

We replaced the long screw with a shorter one to secure the AC voltage regulator to the chassis channel. The batteries fit snugly in the fuel tank.

Then remove the rear truck to more easily mount the RCS charge jack that comes with an RCS #BIK-U3 installation kit.

Then wire in the BIK-U3 switch pcb.

Be sure to get the red/black wires from the BIK-U3 correctly soldered to the rear small pcb on the chassis. The black wire goes to the outside. It is most important to disconnect all four track pick up wires from the loco wiring. These are the two outer wires on each of the 4 way plugs coming from the trucks. RCS did try mounting the RX-8 metal cased receiver up against the rear of the cab wall and stretching the antenna out along the inside of the top of the tender shell. Unfortunately the range was not very good. The best reception was achieved by shortening and connecting the antenna wire to one of the track pick up wires on the rear truck.

The BIK-U3 was mounted in a 1/4" hole drilled in the switch panel just behind the switches. Unfortunately the toggle is a bit long to let the switch cover sit down properly. We chose to cut a bit off the top of the toggle. It might be better to drill a bigger hole and mount a piece of 1/8" styrene underneath the top and drop the switch down that way.

That is the basic installation complete. The socket and switch in front of the AC switches are for a Phoenix P5 + P5t sound system the owner also wanted installed.