Electrics queries before switch on!

[phoenixfc7]

Hi,

I am almost there with the electrics and I have some final queries I hoep you can help:

1 I have a bus bar under drivers seat, can I connect the bus bar to the chassis or does it need to go back to the leisure battery?
2 I have run the negative from the battery to the chassis is this necesary?
3 I have a victron battery charger for use when on hook up only, it runs directly to the leisure battery. To power it can I cut the plug off and wire it into the 6amp fuse breaker of the consumer units? If so should I add a fuse betweet CU and leisure battery? If not should I run a 3-pin from the CU and plug the battery charger in?
4 The solar panel feeds into a Victron MPPT 75/15 the mppt runs into the blade fuse box (easier than into the leisure battery). do I need a switch to disable the solar or would pulling the fuse be sufficient?

Thanks for your help with this

 

[Deaky]

1 I have a bus bar under drivers seat, can I connect the bus bar to the chassis or does it need to go back to the leisure battery?

Yes, you can connect the -ve bus bar to the chassis

2 I have run the negative from the battery to the chassis is this necesary?

If you've connected the -ve bus bar to the chassis then you must connect the leisure battery to the chassis too. If your leisure battery is connected directly to the bus bar then there is no need to connect it to the chassis. However, every piece of leisure electrical equipment must go back to the bus bar.

3 I have a victron battery charger for use when on hook up only, it runs directly to the leisure battery. To power it can I cut the plug off and wire it into the 6amp fuse breaker of the consumer units? If so should I add a fuse betweet CU and leisure battery? If not should I run a 3-pin from the CU and plug the battery charger in?

Yes you can cut the 3 pin plug from your charger and wire it directly to the consumer unit. Not sure what you mean about a fuse between the CU and leisure battery. Your leisure battery must not be connected directly to the CU in any way.

4 The solar panel feeds into a Victron MPPT 75/15 the mppt runs into the blade fuse box (easier than into the leisure battery). do I need a switch to disable the solar or would pulling the fuse be sufficient?

You can disable the charger on a Victron MPPT by switching it off in the app. Pulling the fuse will cause an error.

 

[phoenixfc7]

Thanks Deaky, it is good to know I am on the right lines! Re Q3 i did cut the plug off and wire it into the CU, the battery charger then wires into the positive and negative of the leisure battery. My question is does the battery charger need further protection along the power cable from CU to battery charger?

Once further question, the total of my fuse box is 140 amps, I currently only have a 10mm2 cable from the bus bar to the chasis (same from leisure to chassis), I am thinking I need to beef it up to a 35mm2 or 25mm2. Would you agree?

Thanks for all your help as usual, really appreciated.

 

[Deaky]

Thanks Deaky, it is good to know I am on the right lines! Re Q3 i did cut the plug off and wire it into the CU, the battery charger then wires into the positive and negative of the leisure battery. My question is does the battery charger need further protection along the power cable from CU to battery charger?

Once further question, the total of my fuse box is 140 amps, I currently only have a 10mm2 cable from the bus bar to the chasis (same from leisure to chassis), I am thinking I need to beef it up to a 35mm2 or 25mm2. Would you agree?

Thanks for all your help as usual, really appreciated.

140a what the heck are you running. If the total load of the leisure electrics is indeed 140a then yes 10mm is inadequate. What size is the fuse from your leisure battery to the fuse box?

 

[phoenixfc7]

HaHa! Its more about convenience rather than running at the same time. I've used a 35mm2 from battery to fuse box with a 150amp fuse below is the list:

BLADE FUSE BOX

• Fridge 15amp
• Lights (2) switch 5 amp
• Lights (6) dimmer 5 amp
• USB (1) 10 amp
• USB (2) 10 amp
• USB (3) 10 amp
• 12v (1) 20 amp
• 12v (2) 20 amp
• Victron Mppt 10 amp
• Water Pump 10 amp
• Webasto AT 2000 15 amp

 

[Deaky]

They are the sizes of the fuses that you're using to protect the cable. A USB socket won't pull 10amps. Similarly a 12v socket is rated at max 15a but it's unlikely you'll ever connect anything to it that is that power hungry.

Not sure I entirely agree with connecting your solar charger to a blade in the fuse box. It will mean that disconnecting the battery will not remove the power from your fusebox. If you absolutely must do it then as you have a 75/15 then 10amps is too low. I have loads of LED's, 7 x 12v sockets 5 x USB, Fridge, Eberspaecher and 7 LED dimmers connected to my fuse box and the lot is fused at 40amps and fed with 8mm cable

 

[phoenixfc7]

ok thanks, damage limitation on my pocket here, what would you suggest?

1 I can switch the solar to the battery quite easily
2 I can downgrade the 150 fuse to 30 amp (it was 30 originally)
3 do I need to change the 35mm cable from battery to fuse?
4 could I therefore get away with a 10mm cable from bus to chassis and leisure to chassis?

Thanks

 

[Deaky]

1 Definitely put the solar straight to the battery.
2 Downgrade the fuse, there is really no need for it to be 150a. Maybe 40a
3 No need to change the cable
4 10mm will be fine

 

[phoenixfc7]

1 Definitely put the solar straight to the battery.
2 Downgrade the fuse, there is really no need for it to be 150a. Maybe 40a
3 No need to change the cable
4 10mm will be fine

Thank you!!!!

 

[Deaky]

Just a caveat on the leisure battery to chassis cable, what split charge system do you have in place, if any?

 

[phoenixfc7]

Just a caveat on the leisure battery to chassis cable, what split charge system do you have in place, if any?

ctek d250se

 

[Deaky]

ctek d250se

All good then

 

[phoenixfc7]

Great

 

[phoenixfc7]

ahhhhh ok so I connected everything up and I have a vega 75 on/off/dimmer light that I think I have blown! The fuse blew and I replaced and it immediately blew. Any suggestions? The following is the set up.
105a leisure battery - 35mm2 cable (fused 40amps) to 10 blade fuse box - 10amp fuse - 2.5mm2 cable to vega 75 on/off dimmer

Also as part of the set up I have a ctek d250se going to the leisure battery and 150w solar via an mppt 75/15 to leisure battery. Pictures attached of the set up and a screen shot of what the MPPT has been doing since I connected the system on Tuesday (the volts look high??). any advice welcome (as one scratches ones head).