Musings on Living aboard - Lessons Learned from Electricity
15 April 2016 | Herrington harbour South, Chesapeake Beach, MD
Sunny, Warm
Part-2 of the "musings" series deals with Electricity. Preventive maintenance is important to ensure electricity doesn't cause damage to your boat.
I won't cover the obvious safety risks of dealing with AC power - my focus is more on the lessons I have learned regarding how "current" affects your boat. Current running through your systems can cause interference and physical degradation.
From the interference perspective, without proper fusing, ferrites and grounding many sensitive electronics can be affected by current.
Our most notable interference issue was in our SSB. I spent many weeks hunting the culprit/s of the "hum" in my SSB radio signal. I found four: Refrigerator fan (AC-improperly grounded); 2 x Plug-in electric appliances (space heater, d-humidifier) - it was actually the same outlet used to run either that was not grounded at all! The final culprit was our under-bar ice-maker (which just simply makes electronic noise) - so I turn it off when using the SSB.
So the first musing on current here is every time you add something new to the boat. See if it impacts other systems (like the radio - a pretty critical piece of gear that you want working at the top of its game)! The second musing is don't trust any electrical work (professional or otherwise without a personal inspection). Do it to ABYC standard! If you are in DIY mode - Google the ABYC bible. If someone else is doing it for you - Ask if the work will be done done to ABYC standard - and demand ABYC assurance in writing when tradesmen work on your boat!
Another lesson learned on the AC side was "neutral bonding." This concept is easily found described on the internet. Our issue was with how our BIG Xantrex 2512 Inverter takes and routes power from the genny to the house system. I had poured through the Xantrex manual and discovered that the unit had an "auto-generator start" feature (to crank when the house bank dropped below a predetermined level) that was not working. I discovered it was not even hooked up. I wanted it to work - right! In my months of research and fretting over asking an electrician to do it (an an exorbitant cost), I eventually gained enough personal understanding of the system to DIY. This is where neutral bonding came in.
My need to understand neutral bonding came about as I was trying to add the auto-start functionality feature on our Xantrex inverter system. I'm not an electrician so i am naturally nervous about two things (1) Shocking the $%#@ out of myself and destroying one of my systems by trying to be a DIY'fer. I reached out to both a residential and marine electrician - neither of who's knowledge of the issue comforted me. Ahh..back to Google! I was able to gain a complete understanding of the concept, inspect my system - which was ABYC compliant - and additionally wire the appropriate circuits to add the auto-start feature. I cannot stress the importance of being SURE that the neutral bonding system on your boat is proper and working...for many reasons. Finding (in earlier posts) that I had AC outlets without the ground wire connected prompted me to inspect the entire AC system on the boat - discovering 2 more outlets in the same shape where some DIY'fer has used only 2-lead vs 3-lead tinned marine wire. The second is lightening protection...again - I'm no expert but I wanted to make sure that a BIG Mother Nature lightening charge would go to sea instead of ricocheting through all of my systems (if possible). I had earlier discovered that the SSB was not transmitting due to a previous strike which cost me a 6-week/$700.00 factory repair from ICOM.
The Neutral Bonding "musing"...The best "summary" of understanding this issue (I've found) is at this link:
http://www.qualitymarineservices.net/Neutral-Ground%20Bond,%20Exchange%20Article,%2012-2005.pdf
It really helped me. Piece of mind knowing that you have done the preventive maintenance checks and services of your electrical system is the best insurance when environmental or on-board conditions become unexpected...especially at sea or for safety in the slip.