TEC3M Split charge relay

[ched999uk]

Hey guys I’ve just wired in my tec3m and it seems to be working fine (14v with engine running) but should I still be getting 12.6v to my pump if I bypass the liesure batty with the engine off? Is this not drawing power from my starter battery? 
Thanks in advance ?

Pin 4 will give permeant power from starter battery. Pin 6 or pin 2 is the ones that should be connected to leisure battery. They should only be 12v when the engine is running and starter voltage is high. I believe the switch point can be adjusted but I would just leave it as factory set.

 

[Dmf]

Thanks for the reply and I hope this makes sense ?, but should I still be getting 12v to my pump if I have removed the terminals on the leisure battery? ( with the wires from the relay switch and from the pump controller still attached to the terminal) with the engine off, 

Thanks again 

Thanks for the reply and I hope this makes sense ?, but should I still be getting 12v to my pump if I have removed the terminals on the leisure battery? ( with the wires from the relay switch and from the pump controller still attached to the terminal) with the engine off, 

Thanks again 

Ps I’ve tried 2,4 and 6 but same results 

 

[ched999uk]

Thanks for the reply and I hope this makes sense ?, but should I still be getting 12v to my pump if I have removed the terminals on the leisure battery? ( with the wires from the relay switch and from the pump controller still attached to the terminal) with the engine off, 

Thanks again 

Ps I’ve tried 2,4 and 6 but same results 

That sounds like there is a problem with the split charge relay. I believe they are supposed to voltage sensing. i.e. they measure the starter battery voltage and once that reaches a certain amount that tells it the starter battery is charged and alternator running (at a guess about 13.8v) then it connects the starter batter to the pins 2 and 6. If the starter battery is below the threshold then the split charge relay should disconnect pins 2 and 6 from starter battery. 

One thing. Does your van have a smart alternator or 'start stop' system, how old is the van?

I believe the split charge relay you have has an adjuster in the corner of it, I believe that is to adjust the switch point i.e. the voltage of the starter batter that causes the replay to connect the leisure battery to starter battery. That could be the issue but as it's new I'm not sure.

To be honest this type of relay is designed for a caravan i.e. to top up a leisure battery and power a fridge. It's not really designed to recharged a leisure battery when used by a windy. i.e. your pump might pull 4amps for 5 hrs in a day so 20AmpHrs out of your battery. If you only drive a few miles then you probably won't put much back into the battery.

Hope that gives you some clues?

 

[Davy G]

From my experience I wouldn't consider anything other than a Durite SCR. They seem to be robust and totally reliable and are fitted to emergency vehicles. I had one professionally fitted to the work van a few years ago. Then I bought a complete kit online for the campervan with everything I needed and enough cable to go up to 5 meters from the starter battery to the leisure battery. I fitted this one myself, taking my time, being extremely careful and checking and double checking everything as I went. It was easy enough. I believe they are British made, which is very important to me. For quality and to support our own businesses.

I was browsing recently and saw there is a cheaper  (probably Chinese) lookalike. I wouldn't touch it with a barge pole. Buy quality, Buy British if possible. Buy once. Be done with it. The difference in price is usually not that massive. ?

 

[Den]

Noticed sterling have now released a help B2B with solar charger this could be the future for window cleaners due to being parked up many hours of the day and not doing great amounts of mileage. 

https://www.12voltplanet.co.uk/sterling-pro-batt-ultra-battery-to-battery-charger-12v12v-30a-mppt-solar-controller-350w.html

 

[Pjj]

Noticed sterling have now released a help B2B with solar charger this could be the future for window cleaners due to being parked up many hours of the day and not doing great amounts of mileage. 

https://www.12voltplanet.co.uk/sterling-pro-batt-ultra-battery-to-battery-charger-12v12v-30a-mppt-solar-controller-350w.html

Solar might be ok in the summer to charge up the battery’s but in winter it certainly won’t be any good on its own , I have been talking to my electrician about this I have 2x180 amp AGM extra heavy duty gell batteries ,and run 2-3 pumps ,2 electric reels and a 9kw boiler , he said that so,are wouldn’t charge it ul enough each day and that Ime better off sticking with the charging system that I have rather than adding solar , if just using a pump and reel then it might be worth looking at . 

 

[Davy G]

Noticed sterling have now released a help B2B with solar charger this could be the future for window cleaners due to being parked up many hours of the day and not doing great amounts of mileage. 

https://www.12voltplanet.co.uk/sterling-pro-batt-ultra-battery-to-battery-charger-12v12v-30a-mppt-solar-controller-350w.html

Yeah, it's definitely important to select a charger suitable for the vehicle it's going into.

 

[Den]

Solar might be ok in the summer to charge up the battery’s but in winter it certainly won’t be any good on its own , I have been talking to my electrician about this I have 2x180 amp AGM extra heavy duty gell batteries ,and run 2-3 pumps ,2 electric reels and a 9kw boiler , he said that so,are wouldn’t charge it ul enough each day and that Ime better off sticking with the charging system that I have rather than adding solar , if just using a pump and reel then it might be worth looking at . 

Yes I know what you mean but this is a b2b with added mppt solar controller even my small van would be able to mount 150w solar panel.

glad I can plug cable in each night ? but will help those than can’t and totally rely on there onboard charge systems every little helps ?

 

[okavango]

I am having a problem with the TEC3M relays When I power them up I get nothing I try increasing the voltage to 14.8 still nothing

but if I leave it powered up for about 1 hour it suddenly starts working. This has happened now to 4 different relay all with the same problem I have never come across electronics that needed an hour to warm up.

They seem to work perfectly after the initial start.

Anyone got any ideas?

 

[Davy G]

It's happened with 4 different relays!? I had different makes of relay. None of them confidence inspiring. Three or four years ago I fitted a Durite SCR behind the bulkhead just inside the side door where I can monitor it easily. Very much, fit and forget. Solid and totally dependable. If you go the same route make sure you get one that suits your vehicle. Easy enough to fit DIY but get a comprehensive kit and take great care to follow the instructions. Or get someone who knows what they are doing to fit it.

 

[ched999uk]

I am having a problem with the TEC3M relays When I power them up I get nothing I try increasing the voltage to 14.8 still nothing

but if I leave it powered up for about 1 hour it suddenly starts working. This has happened now to 4 different relay all with the same problem I have never come across electronics that needed an hour to warm up.

They seem to work perfectly after the initial start.

Anyone got any ideas?

I believe the voltage adjustment might work a little different to the way you think. 

Basically what is supposed to happen is when the vehicle starts the starter battery voltage drops so it pulls current from the alternator, this means that the voltage rises. When the starter battery is fully charged (about 12.7v) then the split charge relay should connect the leisure battery to the alternator. 

So when you first start the vehicle the split charge relay wont connect the leisure battery to be charged. It is only connected once the starter battery is fully charged. If you want the relay to switch sooner then you have to lower the switch voltage.

I am simplifying things but lower the relay switch voltage and see what the starter battery is reading when it actually switches.

Just be aware that unless you drive a good distance each day the leisure battery may not get fully charged. Any time you take a lead acid battery below 50% charge (about 12.1v) you damage it slightly. So keep an eye on the voltage and use a mains charger when necessary.

 

[Deleted member 7446]

After the garage letting me down for the second time today "Oh the guy who was going to do that has gone home" thats ok just waste my time mate !!! I have decided to fit it myself which I should of done in the first place! Looks easy enough from instructions but I am not sure what sort of wire I should use

been thinking 30amp wire should

Be ok ?? ( the holes for relay switch are very small) I know i should use a inline fuse just after van battery but what amp should this be? any advice on this would be much appreciated. I have attached a few pics of the relay switch. Thanks

View attachment 6998

View attachment 6999

I know this is an old post however these are utter junk and not fit for purpose. Throwing high currents through these are dangerous 

Durite 0-727-33 are so much better