Muffty Posted March 10, 2012 Share Posted March 10, 2012 Hi, Although I have owned Land Rovers for donkeys years I have never owned a TD5 until now. I would like to fit a dual battery system with a split charging system. I have done this a couple of times on a 90 but now I have the ECU to contend with. If I disconnect the battery will I then need to reset the ECU? will the electrics ie the ECU be able to cope with a dual battery system or will it need reprogramming? Help would be greatly appreciated Quote Link to comment Share on other sites More sharing options...
pupstew Posted March 10, 2012 Share Posted March 10, 2012 hi, im following this with interest cos i was just about to post asking for advice on which choice of dual / split battery system to look at for my 110 td5. Quote Link to comment Share on other sites More sharing options...
eds Posted March 10, 2012 Share Posted March 10, 2012 As far as I know disconnecting a battery will not effect the ECU You can buy a split charge system from Si Xeng who is a member of this forum and supplies a kit and instructions specifically for Land Rovers. After some research I concluded that 2 numax cxv24mf batteries from Tayna batteries is a good setup. Quote Link to comment Share on other sites More sharing options...
Ben_J85JTY Posted March 10, 2012 Share Posted March 10, 2012 I have a dual battery on my TD5 and have no problems at all. The only thing you may have to do differently is that the trigger for the split charge needs to be a VSR rather than a feed from the alternator. You can disconnect and reconnect the battery to your hearts content, and I have no doubt at some point you will have to disconnect the ECU to check the ECu loom hasn't got any oil contamination. Quote Link to comment Share on other sites More sharing options...
western Posted March 10, 2012 Share Posted March 10, 2012 Td5 has a Battery sensed alternator not a machine sensed version like 300tdi & previous engined 90/110/Defenders. Quote Link to comment Share on other sites More sharing options...
martifers Posted March 10, 2012 Share Posted March 10, 2012 Anything with ignition live (position 2 on ignition) is fine to use as the relay live on a Td5. If running components with large current draw aka winches, get a relay that is 'actually rated'.... this site has lots http://www.thetoolboxshop.com/albright-switch-solenoids-405-c.asp I would recommend http://www.thetoolboxshop.com/sw180b-2-albright-single-acting-solenoid-contactor-12v-continuous-6642-p.asp.... what I use or at least this... http://www.thetoolboxshop.com/sw80-390p-albright-single-acting-solenoid-contactor-12v-continuous-sealed-to-ip66-6636-p.asp HTH Quote Link to comment Share on other sites More sharing options...
Pastycrimper Posted March 11, 2012 Share Posted March 11, 2012 If you've got the cash you could get an alternator to battery charger or battery to battery charger.....very effective but expensive - e.g. http://www.sterling-power.com/products-altbatt.htm I'm not recomending this product in particular but the description/picture explains the concept well. Almost all marine applications I work with use these now instead of split charge relays or VSR method. I *think* the battery to battery charger option is cheaper as the starter battery stays exactly as normal but I believe the alternator to battery charger is the best as all batteries are charged and conditioned correctly - certainly all the small work boats I am on use these. Quote Link to comment Share on other sites More sharing options...
vulcan bomber Posted March 11, 2012 Share Posted March 11, 2012 I have a dual battery on my TD5 and have no problems at all. The only thing you may have to do differently is that the trigger for the split charge needs to be a VSR rather than a feed from the alternator. You can disconnect and reconnect the battery to your hearts content, and I have no doubt at some point you will have to disconnect the ECU to check the ECu loom hasn't got any oil contamination. you shouldnt ever take a split charge feed from your alternator, you'll shorten the alternator diode's life alot. Any ignition controlled live will do. You can run twin alternators on a TD5 if you wish, its much better than split charge relays etc. Quote Link to comment Share on other sites More sharing options...
landy andy. Posted March 11, 2012 Share Posted March 11, 2012 Just get two good batteries and a good quality vsr (voltage sending relay) to join them. When the voltage drops below a certain level (engine not running) it will split the batteries, then when it senses higher voltage (engine start) it will rejoin them. Keep it simple Andy Quote Link to comment Share on other sites More sharing options...
eds Posted March 11, 2012 Share Posted March 11, 2012 This is not applicable to a td5....... but which method is superior, a split charge relay taking a feed off the alternator light or a VSR? Quote Link to comment Share on other sites More sharing options...
vulcan bomber Posted March 11, 2012 Share Posted March 11, 2012 This is not applicable to a td5....... but which method is superior, a split charge relay taking a feed off the alternator light or a VSR? Taking a feed from the alternators exciter circuit will fry the diodes in the alternator. Any ignition live will be fine. A volt sensing relay is fine. Quote Link to comment Share on other sites More sharing options...
eds Posted March 11, 2012 Share Posted March 11, 2012 I bought my relay kit from Si Xeng with specific instructions to use the alternator exciter wire to trigger the relay. He specialises in this stuff and is a member of the forum. I thought this was to avoid an important problem, not sure what though. Is this duff information, or has the problem only just come to light or are you thinking I drive a TD5 when in fact it is a 200tdi. If this is bad information, which is the better method for me to correct to. VSR or live ignition relay setup? Thanks Quote Link to comment Share on other sites More sharing options...
vulcan bomber Posted March 12, 2012 Share Posted March 12, 2012 A td5 alternator might be better off that way than the alts the tdi's use etc, if i was you then a volt sensing relay would be my choice.... Although my ultimate choice is 2 alternators as i mensioned above, i run this set up on my 110 and other than a set of brushes packing up in 1 alternator its been faultless. If you go over to the electrical boards on the lro forum theres a welth of info over there if you look for it, i've posted alot, and a user under the name of pistnbroke is a autolecky by trade so knows exacly what he's talking about. Quote Link to comment Share on other sites More sharing options...
Muffty Posted March 12, 2012 Author Share Posted March 12, 2012 Thanks for all the info. it's all useful. Just one thing where do I find this guy 'Si Xeng' I would like to see his kit? Once again many thanks Quote Link to comment Share on other sites More sharing options...
eds Posted March 12, 2012 Share Posted March 12, 2012 http://www.x-eng.co.uk/ Quote Link to comment Share on other sites More sharing options...
simonr Posted March 13, 2012 Share Posted March 13, 2012 I thought I'd reply to the 'Frying Diodes'! There are two types of alternator (actually there are several, but only two fitted to (proper ) Land Rovers. Internally and remote sensed. An internally (machine) sensed measures the battery voltage through the output wires that connect to the battery. Remote sensed measures the battery voltage via the charge light on the dash. IMHO, both have advantages and disadvantages - but that's not relevent here. An internally sensed alternator has a connection to the charge light on the dash. The other side of the light connects to an ignition live. When the ignition is switched on (before the engine is started), the charge light output is connected to battery negative. Since the other side of the light goes to +ve, the lamp lights - showing that the alternator is not charging. The small amount of power flowing through the Alternator is used to pre-energise the field windings - so that when it starts spinning it will generate power. If the charge light is missing / blown, the Alternator will not start generating power. The Alternator has two sets of windings - the field windings and the generator windings. The voltage generated in the generator windings is proportional to the current flowing through the field windings. The internal regulator adjusts the field winding voltage (which changes the amount of current flowing) such that the generator windings produce the required (14.6v ish) voltage. The generator windings produce AC (alternating current - this is why an Alternator is called an Alternator!). There is an internal diode pack which converts the AC into DC (direct current) needed to charge the battery. The field windings are connected to the charge light - so when the alternator is generating, its voltage rises up to battery voltage so both sides of the charge light are at battery voltage - and the light goes out. The regulator which feeds a voltage back into the field windings (which are connected to the charge light circuit) can only generate a small current. This is enough to drive a small relay connected between the charge light output and ground in addition to the field windings. If you use something like a contactor, whose coil may draw several amps - this can overload the regulator and cause damage - however, a relay which only draws a fraction of an amp is safe. Late 300Tdi and subsequent vehicles use the connection to the charge light to measure the battery voltage through the charge light on the dash. If you connect a relay, even a small one between this and ground, it reduces the voltage the regulator is seeing - so it thinks the battery is lower than it actually is. It responds by increasing the voltage being generated - well above the 14.6v required. At the higher voltage, more current flows through the diode pack - possibly overloading it and causing damage (frying diodes). Worse than that, it will over-charge the battery. Thus, on a remore sensed Alternator, you cannot switch a relay using the charge light circuit as it will likely cause damage to your Alternator and Battery. Personally, I'm less convinced about this. I have used a 12v Alternator to charge 24v (two) batteries by connecting the charge light to the first battery and the Alternator output to the pair (24v). In order to get 12v at the first battery, the Alternator needs to spit out 24v - and it seemed quite happy with this! I found the diode pack died when the output reached about 150v (pushing it to see if I could get mains DC) The simplest alternative is to connect the relay to an ignition live which is dead while the engine is cranking. The easiest one to find is the red wire which feeds power into your radio. It is safe to use this regardless of which type of Alternator you have. The only negative of this approach is that when you switch the ignition on to the Acc 2 position, the relay switches on, connecting the batteries together. If you leave it sitting in this state (rather than just passing through it on your way to starting the engine) it may allow the main battery to discharge into the Aux battery (if it's discharged). So with this setup - don't sit in the Acc 2 position for ages before you start the engine. In summary, if you have a 200Tdi or earlier, it's safe to use a small relay in the charge light circuit - but not a big contactor or winch solenoid. If you want to use a contactor, either switch it with a smaller relay or connect it to the radio ignition live. If you have something later than 200Tdi, connect the relay / contactor to the radio ignition live. Why do I like Relay based split charges in preference to VOR (Voltage operated relays) or more complicated computerised split charges? Simplicity and moisture! I have had problems previously with moisture getting into VOR's (and more electronic split charges with flashing LEDs - you know the ones!). On any other vehicle, I would recommend a VOR or more managed split charge - but in a Land Rover which is likely to spend at least some of it's life under water, a simple relay has proven the most reliable. They are easy to test (using a bulb & bit of wire) and easy to bypass if they do go wrong - but most of all, they are inexpensive and on the whole do a good job in high current applications (such as winching). Si n.b. Descriptions of how alternators work may have been simplified. Scenes do not represent actual game footage and sequences may have been shortened. Quote Link to comment Share on other sites More sharing options...
Pastycrimper Posted March 13, 2012 Share Posted March 13, 2012 Thanks for a great explanation Si. My previous alternator (and battery) was fried for exactly the reason you give - the split charge relay was connected via the charge-light and thus the alternator kicked out 19.8V. Glad I noticed this not long after I bought the vehicle and cured the issue. I personally believe that a lot of less knowedgable auto electricians connect the relay via the charge light for the later alternators which is why a lot of people end up having problems with there electrics....after all a 12V electyronics aren't supposed to be running at 20V! I actually take power from the radio feed like you say, but have an in-line illuminated dash switch so that I have to manually operate when the split charge is on and off....I'm anal like that but I like to have full control over whether its on or off. I guess for folks with high winching applications they want the split charge always running when the engines going..... Quote Link to comment Share on other sites More sharing options...
Muffty Posted March 13, 2012 Author Share Posted March 13, 2012 Thanks Simon that was some explanation even I could follow it. I am going for two NUMAX and an Xcharge, when they have them in again. Many many thanks for all the help, i'll be back I'm sure. Allan Quote Link to comment Share on other sites More sharing options...
Muffty Posted March 21, 2012 Author Share Posted March 21, 2012 Hi, where's the split charge boffins? I've opted for a couple of Numax and aT Max relay system the instructions with the E max are illegible on the instruction sheet. Is anyone able to assist with a diagramme. Maybe they think we don't need instructions??? Quote Link to comment Share on other sites More sharing options...
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