Run a ground wire fwd?
The LSE ignition module has two shielded wires for power and ground. The problem is, the instructions say that the ground wire MUST be attached directly to the battery negative terminal and NOT grounded to the frame to avoid electronic noise. They're long, but not long enough to reach my rear-mounted battery.
Questions:
1) Has everybody really grounded to the battery and not to the frame?
2) If anyone has attempted grounding to the frame, was there indeed interference?
3) Can shielded wire be spliced effectively, or do I have to return the entire plug assembly to LSE and have them make one with a longer ground?
Thanks.
I have talked to Klaus before. Not surprisingly people do not always follow this recommendation.
The reason for it, besides noise, for the direct battery connections, POS and NEG, I was told is reliability. There's nothing like a DIRECT connection to the battery. He's trying to avoid going through many conncetions, a master relay and a bus. Wire to battery period, is simple and reliable.
Ground wise, ground is ground. If you read Aeroelectic he has a central ground buss scheme, verse the shotgun grounding approach with random airframe grounds everywhere.
I am sure you are running a big fat POS cable fwd to the front of the plane, right? What are you doing about battery GND? Are you grounding locally in the back of the plane only? If you are, why not run an additional gnd wire, call it a ground strap, fwd. It does not have to be POS wire size but say #8 (or #6). 20 feet will add 1 lb. Probably a wash if you don't have to run the shilded wire aft.
You will still have the big GND cable from the battery NEG to the air frame ground, but this will be another ground wire, but smaller. Run that extra ground to a gnd block up front to the FW. The ground block can be grounded to the airframe locally as well as by the ground wire from the rear mounted battery. So it will be redundant. I doubt it will make noise. Some fear the ground loop. There is a thread on this right now. Personally ground loops are death for audio equip but not your LSE power line.
This ground block could be used to ground other items as well, or only the LSE if you are worried there will be noise.
I think Klaus is most worried about a 100% super reliable simple direct connection to the source of power, the battery. He want the least number of connections and parts between the EI BOX and power.
Now the power side is harder, since you are trying to avoid any device (master relay) between you and your LSE power supply, aka direct battery connection. I assume you are connecting your battery POS cable to a starter solenoid up front on the FW? You can pick the LSE power off that pos battery cable at the solenoid. However this is against Klaus's KISS principle, but many people do it. How many times does a master relay fail after its engaged? George.
