Zig CF8 - Installing a battery guard

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ledixon
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Zig CF8 - Installing a battery guard

Post by ledixon »

Hi all,

I've just installed a new leisure battery and would like to install a battery guard to stop this one from ending up dead too. I have a Zig CF8 unit in my van, which has 3x 10amp 12v outputs, I'm wondering if there is a way to install a single 30amp+ battery guard to protect all 3 outputs or should I just install 3 battery guards (one for each output)?

Battery guard options:

Kemo M148A
Link
Would probably need to install 3 of these as they're only rated for continuous 10amp.

Victron BPR000100400
Link
I could in-theory install just one of these as it's rated for 65amp.

I originally thought I could install the Victron unit between my leisure battery and terminal 4 of the zig unit but the Victron manual says that charge current can't do through it in reverse - which I assume would happen if I did this? Therefore, I'm wondering if could install the Victron to the internal circuit of the Zig unit?

E D I T: To clarity, when I say "install the Victron internally", I mean between the 12v on/off switch and the 3x 10amp loads.

Any advice would be great.

Thanks!

 

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AngeloEvs
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Re: Zig CF8 - Installing a battery guard

Post by AngeloEvs »

The three fused 12v outputs are fed from the CF8 on off switch so you only need to fit one. The rear of the CF8 has a terminal block with some unused, you could take the feed from the on off switch that goes to the common of the three fuses and link it to a spare terminal then use another spare terminal as the return to the common of the three fuses. You can then wire the battery protector to the same terminals. Usually, those three fuses only supply the rear lighting, water pump, etc.

Did you leave something on and forgot to switch the CF8 on-off switch to the ‘off’ position or was it another reason that your leisure battery failed? Leisure batteries are designed to cope with deep discharge unless your battery is a standard type.
1987 DG Karisma LPG with remodelled interior

ledixon
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Joined: 12 Jul 2019, 13:46
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Re: Zig CF8 - Installing a battery guard

Post by ledixon »

Perfect, that’s pretty much what I was thinking for wiring it internally to the zig.

As for the batteries, I’m not really sure why they died as they’ve been in since I bought it. They’ve never been able to get above 11.5 volts after charging. The battery I’m using now isn’t a real leisure battery as it’s going under the passenger seat and I couldn’t get a real one that fit in that space. This is the main reason for the battery guard as I don’t want the battery to discharge too much.

Out of interest, do you know if the zig unit both charges and takes load from the battery through terminal 3 and 4 - depending on the mode? I assume so. I originally thought the leisure battery charged via a relay but I don’t think it’s wired up like that.

Thanks for your help.

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AngeloEvs
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Joined: 22 Nov 2007, 19:22
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Location: Upwell, Norfolk

Re: Zig CF8 - Installing a battery guard

Post by AngeloEvs »

The CF8 charges but does not present a load to the battery when not charging. The only internal current draw is for the battery condition monitor which takes very little current. The charge is direct via a thermal cut out, there is no relay as such.

Be aware that the rear terminal block is organised with all odd numbered connections earthed to the zig case. You can remove an unused earth tab to free up a connection.
1987 DG Karisma LPG with remodelled interior

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