Trying to rephrase and simplify but this will make more sense when you have the relay in your hand. Do not do this if you are not comfortable with the process. Call your friend/family member that is comfortable with wiring and pay them in good alcohol and boat rides after the job is done. Wiring issues are one of the top causes of boat fires. Make sure to use marine rated wire instead of automotive and properly sized connectors. I am actually looking at changing my connectors out because the advice from my "expert" does not match the internet. Those red taps in my photos may be too small. I will update my original post if I do.
**Remember paying a marina mechanic is usually much less than your insurance deductible.
When you get the DVSR you can wire it in 1 wire at a time to replace the existing VSR. At this point you have anti-chatter circuitry and dual sensing (either battery hitting 13.7v will cause the bank to parallel) that you did not have before. The next step is to disable the relay when the engines are not running so that your dual bank charger can work. You do that by tying the red sensing loop on the back of the DVSR into a power source that is only one when the engines are. I used the YDIS/gauge bundle red for this.
The YDIS/gauge connections are the wiring bundles that go up to the gauges. You unscrew the circular cover on the starboard side to get to the bundles. There are 2 identical bundles, 1 for engine 1 and 1 for engine 2. I put a vampire tap on the red wire for engine 2. I did not label my wiring harnesses like they are in the picture, they came from the dealer like that. I ran that wire back around through the loops with the rest of the bundle in the engine bay and up with the battery wires to the BEP cluster. Following the instructions further down in the post from BEP I cut the wire where they said to and trimmed it down fairly close to the relay...big mistake. I had the wrong side of the relay so when I wired everything up my fuel pump came on. Cut the red loop in the middle and tie into it per the instructions then test everything to make sure it is working as expected. Later when you are sure you have everything right you can trim the other end shorter or just seal the end in case you ever want to undo it.
The LED is optional. You can just trim that wire or seal it for later use if you want. I ran the wire back around then engine compartment along-side the wire I ran to sense the engines were running and followed the harness up that side to the helm. I tied into the power line going to the horn with a vampire tap and fuse. That circuit is protected by a 5 amp breaker (
http://www.yamahasportsplaza.com/oemparts/a/yam/5003a1a7f870021f60a1210a/electrical-4) and the wire is rated to 17 amps (thinnest bit of wire from DVSR is 18 awg and the wire runs through the engine compartment (
http://www.boatus.com/boattech/articles/choosing-cables-and-terminals.asp) so it is good for up to 17 amps. If I did this again I would probably just add a bit of wire to create a T on the unfused side and just add a .5 amp fuse on that line if I even did the LED. The thing is really hard to see during the day but it is nice to be able to see the relay status without pulling the seat. In other words I just don't know if the LED is worth it or not.
Here is the process:
0. Take off any jewelry and leave it in the house. Put on eye protection. We are messing with battery voltage here.
1. Disconnect batteries
2. Swap the DVSR for the VSR
3. Reconnect batteries and test with engines on and charger off and with engines off and charger on. Relay should engage with engines on or charger on.
4. Figure out what you want to do as far as sensing loop and LED
5. Identify tie-in points for wiring, note wiring sizes and parts needed to tie in
6. Go to West Marine and spend a little extra for quality marine parts
7. Wire the sensing loop and test with engines on and charger off and with engines off and charger on. Relay should only engage with engines on
8. Wire the LED (optional) and test LED will flash while engaging to show anti-chatter mode then go steady just like LED on DVSR
