TMAX Split charge advice

Hi, i have had TMAX split charge in for a while, i have it fitted with 2 Optima red top batteries, 1 being brand new.

I am sure it never used to continually auto link like it is now, i am sure it only linked when i pushed the manual link.

If i am right in that it should not auto link all the time, could my Solenoid be faulty, i have tried it with other batteries and it does the same thing, i even used a spare tmax monitor that a mate had and still the same.

I will admit i did forget to disconnect it when i charged one of the batteries...(charger was for charging while battery still connected, but don't think it is meant to be connected while a split charge system in use) could this mess the solenoid?

Thanks in advance

Am I the only one who has the tmax?

I've got two T-Max units fitted, one in the Landy and one in the campervan. Both auto link and always have. It's my understanding this is normal when the engine is running. The manual link is there to use when the engine is not running and you need the extra power for a cold start or winching.

That is what is confusing me, why would it link all the time, there should not be any use/power drain on the second battery, i thought it would only link when it sensed the voltage had dropped on the second battery and it needed to charge it. And while in normal use it is not linked as the alternator is charging the main battery.

leejunfan1 said:

That is what is confusing me, why would it link all the time, there should not be any use/power drain on the second battery, i thought it would only link when it sensed the voltage had dropped on the second battery and it needed to charge it. And while in normal use it is not linked as the alternator is charging the main battery.

Click to expand...

is it not just a voltage sensor? ie it links when it detects the alt kicking in, off when not

Mine must have not been working correctly to start with but is now, managed to find the manual online.

Mine never linked unless i pressed the button?

3.AUTOMATIC/MAUNAL BATTERY LINK:
Automatic battery link:
INSTRUCTION MANUAL
1.DISPLAY OF BATTERY VOLTAGE
The battery voltage of each battery is visible for 45 sec after pushing the display button.
Led indicators:
Green: batteries are in the safe working range
Yellow: check batteries.
Red: battery should be charged
12.6v=100%
12.4v=75%
12.2v=50%
12.0v=25%
Led display:
Red light: >14.5v: batteries will be overcharged, damage to batteries may occur
Yellow light: >14v: standard battery charging mode
Green light: < 14v: save charge mode, no damage to batteries.
While the engine is running the main and aux batteries are linked together for parallel charging from the alternator (green led linked is on). If the engine is stopped, the two batteries will be disconnected automatically with some delay. Appliances as fridges, lights, compressors, inverters are now safely fed from the aux battery The dual battery system links the two batteries automatically for charging and isolates the two batteries for discharging. The illumination of the green led indicates that the batteries are linked. The dual battery system recognizes charge on both batteries (alternator on main battery or solar power/charger on auxillary battery) and links the
batteries.

i'd check the wiring is still clean and tight.

if the unit starts going nuts, then you can junk it and buy a voltage sensing relay and separate 200amp relay for <£30 delivered

It seems to be working as the manual states, must have missed that part of the instructions when i installed it... After a few seconds starting the engine, i hear the click and the auto link lights up, on turning off, about 10 seconds later it un-links.

I checked all the connections and cables when i thought this was wrong and all are good, clean and tight.

just goes to show, re-read the manual and not presume your own logic is correct.