There is always something to do...
Our Eberspacher (boat heating) works a real treat when we're alongside and connected to shore power and the battery charger is keeping the batteries nicely topped up. At anchor however it's a different story. The problem is at initial startup the heating draws nearly 30amps for 5 minutes or so and if the batteries aren't fully charged the voltage loses by the time it reaches the heating unit are such that the system just shuts itself down.
With our longer term plans to sail earlier and later in the season it would be nice to be able to call on the heating as necessary so we needed to find a cost effective solution.
Our batteries are reasonably new and hold their charge, but it could be argued that the wires from the batteries to the distribution panel were slightly undersized and the bus bars would certainly benefit from an upgrade.
Before ripping out the wires to the distribution panel we decided to upgrade the bus bars first together with a couple of short wires relating to the central heating. Our bus bars are original (30 years old) and pretty basic as you can see from the picture below.
existing bus bar - pressed plate with push on terminals on a piece of perspex
The wiring/cable management wasn't great either and would certainly benefit from a bit of organisation.
We ordered the parts from our preferred European supplier www.svb24.com
now that the UK has left the EU in order to avoid the excessive import charges that now apply.
With a few hours effort the new bus bars were installed successfully and all the existing cables were reconnected with fresh ring terminals.
new bus bars and wiring reconnected
a test crimp to confirm we were using the right die and pressure
Now the moment of truth :-
With both our mains battery charger and solar panels switched off for 24hrs and the state of charge of our batteries down to around 80% we tried the heating......
Success!! This is the first time we've started and run the heating without the battery charger running! Without doubt the internal resistance of the old bus bars and connections was so significant it was the cause of the problem.
As an aside many weeks later we have observed that we are getting significantly less interference on a number of our radio devices like our Radio Telex (Weatherman) , Navtex and our SSB receiver all of which were getting power from the same bus bar.