Ground Fault protection on a Boat -- Help

[Narrowboat boy]

Hi All

We are installing the Classic on my Narrow Boat , In the manual it says " If the internal grounding Jumper is installed in a classic , The battery negative  and DC Source must NOT be Connected to the System grounding conductor anywhere in the system "  The problem is on a Boat it is as standard . It is all earth bonded to the Engine mount as earth

am I reading this right that as shipped GFP will not work on my Classic application or do we have to do something else during installation or even turn GFP off . Any advice on best and safe installation gratefully received .

Also in the wiring diagram on page 25 of the manual it only shows 3 wires going to the classic Terminal block no PV negative , this has my engineer confused . Can anyone elaborate on this or are just reading too much into this generic diagram .

We have a simple system ( at the moment until diversion is installed ) with 2 x inputs from a combiner box to the classic and then 2 wires to the batteries albeit via Whizzbang jr and fuses etc but it is a Boat which is earth bonded hence GFP question above .

[boB]

The two negative connections on the Classic are connected together right at that connector.    What that means is that you can connect the PV negative and the battery negative together where the wires run in....  i.e.  at the common negative bus and then just run one wire from Classic to that common negative bus in the main connector box.

You can also, if you wish, connect the PV negative to the PV minus terminal on the Classic and the battery minus to the battery negative terminal on the Classic's wire terminal block.   Just saves 1 wire doing it the first way.

As far as the GFP connection, just pull that jumper wire if you want to and let the GND to chassis (boat hull) connection be done where it is already connected to battery minus.

If this did not answer the question, and it may not have, please wait for an answer here AND/OR call our support line from  360-403-7207

I'm not exactly sure myself of the best route to take on that GF thing.

[Narrowboat boy]

The two negative connections on the Classic are connected together right at that connector.    What that means is that you can connect the PV negative and the battery negative together where the wires run in....  i.e.  at the common negative bus and then just run one wire from Classic to that common negative bus in the main connector box.

You can also, if you wish, connect the PV negative to the PV minus terminal on the Classic and the battery minus to the battery negative terminal on the Classic's wire terminal block.   Just saves 1 wire doing it the first way.

As far as the GFP connection, just pull that jumper wire if you want to and let the GND to chassis (boat hull) connection be done where it is already connected to battery minus.

If this did not answer the question, and it may not have, please wait for an answer here AND/OR call our support line from  360-403-7207

I'm not exactly sure myself of the best route to take on that GF thing.

Hi boB

Thanks for the answers , that clears up negative line but we are still puzzled about GFP surely all boats and RV’s are the same how do they do it , I have seen many vids online where US skoolie and RV customers turn on the classic “out of the box “ without problems yet they will be wired the same as my boat .

Clarification on the meaning of the manual would be great .

If we leave gfp on what are the issues ? Seems to me to be just a smart fuse .

FYI GFP is not a legal requirement on Pv systems in uk . Maybe the wording is geared towards the requirements in the US ?

Simon

[Narrowboat boy]

Ok update

We left GFP connected and it didn’t work , as soon as I started the engine the alarm sounded . The starter motor had little resistance so I can understand why as feared this would look like a ground fault to the classic we disabled GFP and it’s now ok . But I still want to know what all the RV people do in USA do you wire your earths different to the worldwide norm for vehicles and boats ? Or is everyone Disabling the gfp ?

Apart from that so far am loving the classic very much even thought not yet got complete array connected . It’s streets ahead of all other charge controllers I have seen on narrowboats .

[ClassicCrazy]

I think in most  RV the starter motor is isolated from the other batteries in the power system .  They would have a separate battery for starting and some kind of isolater so the power system wouldn't ever run down the starting battery but the engine could still contribute to charging the other batteries- used to be a diode but modern ones might be different these days.

Larry

[boB]

However you get it to work should be fine.

There are no regulations on Ground Fault for boats, luckily !

[Narrowboat boy]

We disabled GFP and that works fine .

Larry on boats the Negative and Earth are bonded hence the issue Everything is earthed to the engine , The starter battery is isolated from the domestic bank for discharge but its on the same charging circuit . We dont think GFP can work on a Narrowboat .

boB correct no rules on boats or indeed I believe in UK full stop to have GFP on PV arrays right now, Just thought it would be nice to have and my Marine engineer was worried by the language in the manual saying it should definitively not be disabled etc , The fact it is very easy to do so lead me to believe the wording is based on the legal need to comply in USA rather than causing the Classic to explode or anything ?

Simon