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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5851

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
Linking batteries
Currently I have a 80amp relay which is used in a split charge setup. This is triggered by an ignition on feed (taken from the radio power feed)

I have a spare winch soleniod from a Warn X6 winch, I am thinking of replacing the relay with said soleniod so I can link two batteries together to aid cold starting, and also in the event of a flat battery to save getting the jump leads out.

I was thinking of a switch on the dash set to

Auto - so the split charge works as normal and the two batteries disconnect when the engine is off

Linked - so the two batteries become joined for starting

Off - as it says, not linked/not split charging

Does this sound doable? 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #477913 1st Dec 2015 9:29am
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Cupboard



Member Since: 21 Mar 2014
Location: Suffolk
Posts: 2971

United Kingdom 2011 Defender 110 Puma 2.4 HT Corris Grey
that sounds perfectly sensible.

Have you deliberately chosen to use an ignition feed rather than a VSR? If you run the second battery down then turn the ignition on, your starter battery will be trying to charge the second one which isn't very helpful if you're also trying to start the engine.

The other thing is have you looked at the specs for your current relay? It might be that it can stand a few hundred amps for the few seconds you need to start.
Post #477982 1st Dec 2015 1:41pm
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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5851

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
The reason being for not having a VSR is simple....I didn't have one!
It is something I am thinking of adding instead of the ignition feed activated relay.

The relay I am not 100% of its rating, it could be 80amp with 120amp peak.... ?
TBH, a winch relay is probably better for the job than a relay ? 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #478006 1st Dec 2015 4:04pm
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VeeTee



Member Since: 06 Mar 2011
Location: Somewhere
Posts: 1512

Netherlands 
There's also the VSR with built-in Start Assist function, e.g. the Cyrix has this. You could combine this with a switch in the negative feed of the Cyric, then you have exactly the setup you want:

Auto (start assist switch off, negative feed on)
Linked (start assist switch on, negative feed on)
Off (start assist switch off, negative feed off)

With a bit of creativity it might be possible to combine the switch functins in one switch.


Click image to enlarge
 Cheers, Vincent
1959 Polynorm 1/4 Ton Trailer, Olive Drab Green (sold)
1970 M416 Military Trailer (Camping Trailer Conversion), Epsom Green (sold)
1975 Series III 88 V6, Light Green (sadly sold)
1996 Defender 110 CSW 300 Tdi, Epsom Green (sold)
2000 Freelander 1 TD4 3-drs, Silver (sold)
2006 Freelander 1 TD4 5-drs Facelift Automatic, Tonga Green (sold)

MySite
Post #478009 1st Dec 2015 4:22pm
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roel



Member Since: 08 Aug 2009
Location: Lelystad
Posts: 2039

Netherlands 2003 Defender 90 Td5 PU Caledonian Blue
Normally a winch soleniod is not to be powered hours a time. Surely the old ones didn't like that. Whistle Roel

1984 90 2.5 na Diesel - RR V8 (1994-2001)
1997 Camel Trophy Discovery 300TDI (2001-2009)
2005 G4 Discovery III 4.4 V8 (2008-2018) It's gone but it still hurts.
2003 90 Td5 (2009-now)
Post #478107 1st Dec 2015 7:49pm
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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5851

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
The idea came from seeing this
http://www.ebay.co.uk/itm/T-MAX-12V-Digita...xyXzxTGYXt
which has a 250amp continuous rated solenoid. 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #478111 1st Dec 2015 7:55pm
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