Electrickery for camping

[a2iPhoto]

Your expertise on the below would be appreciated.

I have built in an intelligent battery charger (Victron 12v/15A) into my Ranger for the times we are camping at sites with power. To avoid having cables all over the place, I installed an external IP67 caravan type plug on the outside of my RSi canopy (picture below).

The battery charger has a two pole plug which I plan on cutting off and connecting to the external caravan plug. The external power source from campsite is 3 pole.

The question - should I earth the caravan plug on canopy to the body, or would it not really serve a purpose? There is a canopy support bolt (attached to steel bracket on body of vehicle) just below the caravan plug which could easily be used as earth?

Many thanks.

[ChrisWanzenbergh]

Good day,
If you want to earth any 220 Volt, I wouldn't earth it to the vehicle cause the vehicle stands on rubber wheels, isolating it from earth,,, do you remember the old cars used to have a chain hanging from the body to the ground. That will earth the vehicle. Maybe not secure but in most cases it should work.

[LiamG]

Good afternoon helpful forumites

I have recently bought a trailer with a Victron Blue Power PWM (12/24). I have an 80W panel that I use on my truck, my intention is to buy another 80W panel and build a solar suitcase for use on the trailer. But I see that the PWM can take maximum 55V only. How would I connect the panels not to exceed the voltage? What would happen if the voltage were to exceed 55V?

Thanks

Liam

[Dungbeetle]

Good afternoon helpful forumites

I have recently bought a trailer with a Victron Blue Power PWM (12/24). I have an 80W panel that I use on my truck, my intention is to buy another 80W panel and build a solar suitcase for use on the trailer. But I see that the PWM can take maximum 55V only. How would I connect the panels not to exceed the voltage? What would happen if the voltage were to exceed 55V?

Thanks

Liam

Connect them in parallel
Join the + of both panels
and join the - of both panels

Your max voltage will be the same as for 1 panel

If you join in series you will exceed 55V and the PWM might lose its smoke...

[LiamG]

Connect them in parallel
Join the + of both panels
and join the - of both panels

Your max voltage will be the same as for 1 panel

If you join in series you will exceed 55V and the PWM might lose its smoke...

Brilliant thanks Dungbeetle

[mplester]

Liam, if you connect the panels is series you increase the voltage and the amperage remains the same. Parallel will keep the voltage the same and increase the amperage.
Two panels in series will still be well below the Vmax of your victron. The great thing about having 2 panels installed in parallel is that if the controller fails when in the bush you can still charge your battery directly. Not ideal and you would need to keep an eye on things but it would work.

[Dungbeetle]

Careful

We do not know what the Voc of Liam's panels are

You do get 80W panels with 36V Voc...

[LiamG]

Careful

We do not know what the Voc of Liam's panels are

You do get 80W panels with 36V Voc...

They're these jobbies https://www.4x4direct.co.za/fixed-so...l-18-volt.html

[TRON]

They're these jobbies https://www.4x4direct.co.za/fixed-so...l-18-volt.html

No problem the controller takes the 18V down to what is required to charge your 12V battery. The panel you have was designed for a 12v system. If you now want to get a 2nd panel put them in parallel and then you will be safe.

If in series you need to just make sure that the controller can step the charge voltage down for your 12V battery setup.

[Dungbeetle]

BlueSolar PWM-Light 12/24-5 12/24-10 12/24-20 12/24-30Battery Voltage 12/24V with automatic system voltage detection
Rated charge current 5 A 10 A 20 A 30 A
Recommended solar array 36 cell for 12 V / 72 cell for 24 VAutomatic low voltage loaddisconnect

Maximum solar voltage 28 V for a 12 V system and 55 V for a 24 V system

(1)Self-consumption < 10 mAOverload protectionShut down after 60 s in case of 130% loadShut down after 5 s in case of 160% load
Short circuit: immediate shut downGrounding Common positiveOperating temp. range -20 to +50°C (full load)Humidity (non condensing) Max 95 %

Stick to Parallel........

[Bosvark_1000]

I read in the 75/15 manual they recommend 2x 12v (36cell) panels in series or 1x 24V(72cell) panel.
The higher voltage makes the regulator more efficient in the sense that it will provide charge for a larger part of the day, meaning the panels will reach a higher voltage earlier in the morning and stay at a higher voltage later in the day.
I also assume the auto voltage detects means the regulator will step the voltage down to 12V for the battery?

From the victron manual:
For example:
12V battery and mono- or polycristalline panels connected to a 75V controller
● Minimum number of cells in series: 36 (12V panel).
● Recommended number of cells for highest controller efficiency: 72
(2x 12V panel in series or 1x 24V panel).
● Maximum: 108 cells (3x 12V panel in series)

[mikeml]

I read in the 75/15 manual they recommend 2x 12v (36cell) panels in series or 1x 24V(72cell) panel.
The higher voltage makes the regulator more efficient in the sense that it will provide charge for a larger part of the day, meaning the panels will reach a higher voltage earlier in the morning and stay at a higher voltage later in the day.
I also assume the auto voltage detects means the regulator will step the voltage down to 12V for the battery?

From the victron manual:
For example:
12V battery and mono- or polycristalline panels connected to a 75V controller
● Minimum number of cells in series: 36 (12V panel).
● Recommended number of cells for highest controller efficiency: 72
(2x 12V panel in series or 1x 24V panel).
● Maximum: 108 cells (3x 12V panel in series)

The quoted controller efficiency is normally the efficiency of the controller converting the solar input to battery output, ie equipment efficiency. Generally, the higher the input voltage, the higher the efficiency.

Then you have the "efficiency" you explained above

[Bosvark_1000]

The quoted controller efficiency is normally the efficiency of the controller converting the solar input to battery output, ie equipment efficiency. Generally, the higher the input voltage, the higher the efficiency.

Then you have the "efficiency" you explained above

Correct

Then a "better" setup on the victron 75/15 will be 2x 100W 72cell panels in parallel. You increase the voltage so you should get longer hours of charging.

[lirritma]

After my AGM decided that it will no longer accept a charge, I decided to give a lead crystal battery a go. No particular reason. I don't use my aux that often so it cannot do any harm to try another option.

I use it for a 40l Engel and a few 12v attachments like lights and battery charging. Has a 500Watt inverter attached as well. Also plug my air pump into it but when the engine is running. Has a WRND dc/dc (with MPPT) with a 120Watt mojave solar panel for when I'm in camp on my bum with a cold one in the shade.

So which lead crystal battery would you suggest please?

[Half-Pint]

Ok so at the outset of my questions let me just say that I find electricity a very confusing topic and class those who understand it and work with it in the same category as wizards and snake charmers. Something beyond us mere mortals.

Nevertheless I am trying to educate myself around this topic and have (I think) progressed quite far from my starting point.

My question is when connecting a volt and amp meter per the 4x4 direct wiring diagram below, what is the amp meter actually measuring? Is it the current leaving the battery? Is it the current entering the battery? I presume that it is the former?

Then if I follow ChrisF's guidelines from a few years ago (which I may be misinterpreting) and change the wiring from the diagram so that the WRND or other charger takes the place of the battery and the battery takes the place of the spotlight or load I should be able to tell what voltage and current is being put into the battery?

[Dungbeetle]

My question is when connecting a volt and amp meter per the 4x4 direct wiring diagram below, what is the amp meter actually measuring? Is it the current leaving the battery? Is it the current entering the battery? I presume that it is the former?

Well both is correct as the current is the flow in the closed circuit - what is flowing out is also what is flowing in the battery, else something external is supplying or drawing....

If you are going to add chargers etc. you need 2 of those meters
- 1 in the load circuit
- 1 in the charge circuit

Or get one from HcdP - which measures bi-directional.
It gives you positive when the load is less then the charge and negative when the load is more than the charge

http://www.hcdpelectronics.co.za/ind...&product_id=60

[lirritma]

After my AGM decided that it will no longer accept a charge, I decided to give a lead crystal battery a go. No particular reason. I don't use my aux that often so it cannot do any harm to try another option.

I use it for a 40l Engel and a few 12v attachments like lights and battery charging. Has a 500Watt inverter attached as well. Also plug my air pump into it but when the engine is running. Has a WRND dc/dc (with MPPT) with a 120Watt mojave solar panel for when I'm in camp on my bum with a cold one in the shade.

So which lead crystal battery would you suggest please?

Anybody with input on my question? I got quote yesterday of R5000 for a 100Ah Lead Crystal battery from Batteries Online and it looks like it is a Betta Battery.

[Rooikop]

After my AGM decided that it will no longer accept a charge, I decided to give a lead crystal battery a go. No particular reason. I don't use my aux that often so it cannot do any harm to try another option.

I use it for a 40l Engel and a few 12v attachments like lights and battery charging. Has a 500Watt inverter attached as well. Also plug my air pump into it but when the engine is running. Has a WRND dc/dc (with MPPT) with a 120Watt mojave solar panel for when I'm in camp on my bum with a cold one in the shade.

So which lead crystal battery would you suggest please?

I have 2 of the Deltec Lead Crystal 12V 100Ah which have been doing duty now for 5years and which I bought directly from Deltec in Alberton. One should be adequate to run all of the items that you have mentioned.

It is also a Betta battery, and do I see that Deltec have a branch in Cape Town as well.

[lirritma]

I have 2 of the Deltec Lead Crystal 12V 100Ah which have been doing duty now for 5years and which I bought directly from Deltec in Alberton. One should be adequate to run all of the items that you have mentioned.

It is also a Betta battery, and do I see that Deltec have a branch in Cape Town as well.

Thanks Rooikop. Do you have the BC-6CNFJ-90 or the BC-6CNFT-100 ?

[a2iPhoto]

After my AGM decided that it will no longer accept a charge, I decided to give a lead crystal battery a go. No particular reason. I don't use my aux that often so it cannot do any harm to try another option.

I use it for a 40l Engel and a few 12v attachments like lights and battery charging. Has a 500Watt inverter attached as well. Also plug my air pump into it but when the engine is running. Has a WRND dc/dc (with MPPT) with a 120Watt mojave solar panel for when I'm in camp on my bum with a cold one in the shade.

So which lead crystal battery would you suggest please?

There are a number of very good technical articles in the past month's SA4x4 magazine. A lot of good is said about the Discover Dry Traction batteries - slightly higher Ah (115Ah if I remember correctly) and longer lifespan. As far as I understand, the Lead Crystal batteries do not like a lot of shaking, whereas the Dry Traction is much more robust...