A couple of days ago my Isolation Transformer (IT) started acting up, popping one of the 16A breakers whenever some serious load was put on but still well under the maximum load.
After a quick contact with Victron, it turned out that the breakers themselves are to blame and that new models do not have these anymore. I was advised to replace them with jumpers.
Here's the transformer:
Remove shorepower before opening the unit. When opened, this is what appears:
The circuit board is mounted with 6 screws: 2 at the top and 4 at the bottom. Here is a close-up of the two breakers:
Also check the tiny FAN cable. It has a connector on the circuit board and needs to be pulled to do the patch. The green ground cable in this picture is the shorepower input ground. This cable is right in front of one of the screws so had to be removed too.
I tried to de-solder a breaker but my PortaSol butane powered iron doesn't have enough power for the large leads which are in fact crimp quick-connect terminals. So I decided to leave the breakers in place and mount small jumpers onto their leads on the back of the circuit board:
If you make the jumpers as tight as I am doing here, it will fit behind the circuit board while mounted in the unit. The terminals on the right show my attempt at removing the solder with vacuum pump which utterly failed with my too small soldering iron. I resoldered the connections and added a jumper like for the other one.
When done re-assemble and do not forget the chassis ground cable which is attached to one of the circuit board screws:
When the unit is closed, mark that the breakers are disabled on the lid near the breakers.
I do not exactly know when Victron started selling these without the breakers, so check your unit. The materials I used for this patch should be aboard every cruising sailboat so there is not really a need to do this before a breaker fails. Make sure you use a quality ratcheting crimper and hi quality terminals. Use tinned marine rated multi-strand AWG14 wire.
Also note that your installation might have counted on these breakers for code conformance. You should add external breakers between the shore power inlet and the IT in that case.
This patch can be done in an hour incl. coffee break.
ciao!
Nick.
Hi, first of all compliments, great site! Question: I have a newer model from Victron - and in mine I had to connect the PE from the input with the J34A connection. This enables the isolation as per manual - I made the connection longer as I can use this if the boat would be on land and needs a different connection to be safe. Since I cannot see either one of this connection may I ask why you not use this?
Cheers Marco
Posted by: Marco | 09 March 2012 at 21:43
Hi Marco, I think that the jumper you mention must only be placed when the boat is out of the water. It connects shore ground to boat ground IIRC and this is exactly what you do NOT want with an isolation transformer.
Measure resistance between the ground pin on your shore-inlet (remove shore power cord) and the output ground of the transformer. There should be NO connection there.
ciao!
Nick.
Posted by: Nick Vermeulen | 12 March 2012 at 11:21