I have a CD25 with a outboard with a electric start and generator. VHF radio only. The electrics are laid out this way. One battery, negative lead off the battery goes to a buss with all negative leads to the buss, including the outboard lead. Also off the negative buss lead to the dynaplate. Positive lead off the battery goes to master switch, all positve leads except for the bilge pump downstream from the master switch. Outboard has a zinc, through hulls are not bonded. My question is should the dynaplate be off the main negative buss? My priority is to reduce any possible electrolytic corrosion with the outboard. What does the dynaplate do in the system? Does the dynaplate help prevent electrolytic corrosion or is the outboard the path of least resistance? Any electrical experts with some thoughts?
--------------------------------------------------------------------------------
tomb5050@aol.com
Electrical System Question
Moderator: Jim Walsh
-
Stuart
Good Ques.
Good Question. I too would be interested in knowing that answer.
st1975@yahoo.com
Tom Babington wrote: I have a CD25 with a outboard with a electric start and generator. VHF radio only. The electrics are laid out this way. One battery, negative lead off the battery goes to a buss with all negative leads to the buss, including the outboard lead. Also off the negative buss lead to the dynaplate. Positive lead off the battery goes to master switch, all positve leads except for the bilge pump downstream from the master switch. Outboard has a zinc, through hulls are not bonded. My question is should the dynaplate be off the main negative buss? My priority is to reduce any possible electrolytic corrosion with the outboard. What does the dynaplate do in the system? Does the dynaplate help prevent electrolytic corrosion or is the outboard the path of least resistance? Any electrical experts with some thoughts?
--------------------------------------------------------------------------------
st1975@yahoo.com
-
Murray Glue
Re: Well...
The normal negative grounded system on a boat also implies that the motor, shaft, and underwater fittings are also at negative ground potential, unless the original installation was done in two pole isolated mode and has been maintained in that state ( which is rare indeed ).
I am not an outboard expert, but if this has a negative ground internally, then to avoid different potentials and therbey creating circuits through seawater the dyna plate should be isolated, and used for its normal function as a radio ground.
Since your VHF is probably also negative ground, and since it doesnt realy require a ground plate to radiate efficiently, it might be better to disconnect the dynaplate altogether.
This issue is case specific of course, but by using a galvanometer and silver half-cell tester you can check the potential of each underwater part and deduce what is going on.
Hope this helps...
Murray Glue
Dayspring CD30
New Zealand
murray@offshoretechnical.com
I am not an outboard expert, but if this has a negative ground internally, then to avoid different potentials and therbey creating circuits through seawater the dyna plate should be isolated, and used for its normal function as a radio ground.
Since your VHF is probably also negative ground, and since it doesnt realy require a ground plate to radiate efficiently, it might be better to disconnect the dynaplate altogether.
This issue is case specific of course, but by using a galvanometer and silver half-cell tester you can check the potential of each underwater part and deduce what is going on.
Hope this helps...
Murray Glue
Dayspring CD30
New Zealand
Stuart wrote:Tom Babington wrote:
------------------------------------------------------------------
murray@offshoretechnical.com