Time for new panels...

[mudski]

Why not fit the Relay to the camper and wire the changeover relay sense wire (+ve of the coil) to the input of BCDC.

When no voltage is present at the BCDC Alternator input the relay will be "relaxed" and directing Mains powered 12 volts to teh batteries

When voltage is present it will be "energised" and therefore knows it is hooked up to the Car and switch.

P.S. Cuppas right. Big Panels are an absolute PIA, been there, done that, couldn't wait to not do that anymore

Mate, there's nothing evil about you!!!! More so an angel... Great so I will go get a change over relay now and will be back asking more questions....

[the evil twin]

Mate, there's nothing evil about you!!!! More so an angel... Great so I will go get a change over relay now and will be back asking more questions....

Hold onto the hugs until we make sure it works... them eggs are dangerous critters and can attack your face without warning

[Bloodyaussie]

What are you doing with your old panels???? he he

[mudski]

What are you doing with your old panels???? he he

Gonna convert them into a bi-fold camp table.

[mudski]

Why not fit the Relay to the camper and wire the changeover relay sense wire (+ve of the coil) to the input of BCDC.

When no voltage is present at the BCDC Alternator input the relay will be "relaxed" and directing Mains powered 12 volts to teh batteries

When voltage is present it will be "energised" and therefore knows it is hooked up to the Car and switch.

P.S. Cuppas right. Big Panels are an absolute PIA, been there, done that, couldn't wait to not do that anymore

Just to clarify on the bold section. A bit confused here. The mains charger I have removed, for now. As I want to get the 1225 sorted. So the mains 12V powered could be solar power?
Then after the 1225 is in. I assume to reinstall the mains charger I would just wire up the output wires to one of the batteries. This won't hard the dc-dc charger at all?

[the evil twin]

Just to clarify on the bold section. A bit confused here. The mains charger I have removed, for now. As I want to get the 1225 sorted. So the mains 12V powered could be solar power?
Then after the 1225 is in. I assume to reinstall the mains charger I would just wire up the output wires to one of the batteries. This won't hard the dc-dc charger at all?

Now you've confused me... what do you want your "changeover relay" to switch between?

I pictured one thing but actually now I think you are after...
Pin 30 Batteries
Pin 87 Mains Charger +ve Output
Pin87A BCDC output
Pin 86 Mains Charger +ve Output
Pin 85 Earth

When no 12 volts is available from the Mains Charger the relay is relaxed and the BCDC supplies charge (regardless of whether it is Solar or Vehicle input to the BCDC)

When there is 12 volts from the mains charger the relay energises and the Mains Charger supplies the charging voltage and teh now open 87A contact isolates the BCDC from the Mains Charger

[mudski]

Now you've confused me... what do you want your "changeover relay" to switch between?

I assume it need the relay to switch between solar and dc-dc charging. As per instructions it says I need one for when having both Solar and dc-dc wired in...No mains charging.
12v and solar.jpg

I pictured one thing but actually now I think you are after...
Pin 30 Batteries
Pin 87 Mains Charger +ve Output
Pin87A BCDC output
Pin 86 Mains Charger +ve Output
Pin 85 Earth

When no 12 volts is available from the Mains Charger the relay is relaxed and the BCDC supplies charge (regardless of whether it is Solar or Vehicle input to the BCDC)

When there is 12 volts from the mains charger the relay energises and the Mains Charger supplies the charging voltage and teh now open 87A contact isolates the BCDC from the Mains Charger

Yep. I understand that bit. As I physically have two charging units, the mains charger that came with the trailer and now the dc-dc charger.
Thinking out aloud here...remember I have removed the mains charger for now.
I was to hook up the dc-dc charger as per instructions with the relay connected somehow. Then to re-install the mains charger by simply attaching the two output positive and negative wires to one of the batteries to charge both whilst at home.
But I am worried if I wire it in this way I will damaged the dc-dc charger.

[mudski]

Now you've confused me... what do you want your "changeover relay" to switch between?

I pictured one thing but actually now I think you are after...
Pin 30 Batteries
Pin 87 Mains Charger +ve Output
Pin87A BCDC output
Pin 86 Mains Charger +ve Output
Pin 85 Earth

When no 12 volts is available from the Mains Charger the relay is relaxed and the BCDC supplies charge (regardless of whether it is Solar or Vehicle input to the BCDC)

When there is 12 volts from the mains charger the relay energises and the Mains Charger supplies the charging voltage and teh now open 87A contact isolates the BCDC from the Mains Charger

Man this takes a while for me to get around. That should work so the main charger and BCDC charger switch over but then I need to do it again for the solar and dc-dc charger on the BCDC to switch over.
Running one C/O relay to switch between the two chargers and then another to switch between solar and dc-dc.
I'm so close.


If I do as the diagram says, I need to get power to the switching pin #86 on the relay. The only two ways I see it happening is a manual switch, seeking power from the camper batteries, or, running a switching wire from the car. Like the diagram says. But thats not feasible.

[Cuppa]

The changeover relay has nothing to do with a mains charger!

It's purpose is to make the switching between alternator & solar automatic. Basically when ignition is turned on the relay connects the alternator to the bcdc, & when ignition is turned off the relay connects the solar to the bcdc. Unlike some setups the bcdc chargers use either/or solar & alternator, not both together.

The changeover relay could be replaced with a manual switch provided your memory is good enough to always switch over when setting up & breaking camp. The automatic setup is very convenient when fixed panels are used. Install & forget.

[mudski]

The changeover relay has nothing to do with a mains charger!

It's purpose is to make the switching between alternator & solar automatic. Basically when ignition is turned on the relay connects the alternator to the bcdc, & when ignition is turned off the relay connects the solar to the bcdc. Unlike some setups the bcdc chargers use either/or solar & alternator, not both together.

The changeover relay could be replaced with a manual switch provided your memory is good enough to always switch over when setting up & breaking camp. The automatic setup is very convenient when fixed panels are used. Install & forget.

Sorry Cuppa, I see you are frustrated. Try being me! But ET has explained how to use a change over relay for the two chargers. DC-DC and the mains charger.

But to your explanation. How do I get the switching wire from the ignition (as per instruction says) to the relay on the trailer?

The automatic setup is very convenient when fixed panels are used. Install & forget.

Fixed as in permanently mounted? This setup isn't if it makes a difference.