Absorb and bulk times

[russ_drinkwater]

Is there a way to program how long the classic stays in these modes?
Or is it controlled by the battery voltage the classic analyses results?

[Resthome]

Is there a way to program how long the classic stays in these modes?
Or is it controlled by the battery voltage the classic analyses results?

It stays in Bulk Mode until it reaches the Absorb voltage set point. It will stay in Absorb how ever long you have the Absorb Timer set to as long as you are not using END AMPS.

[russ_drinkwater]

Hi,
I have not set the absorb timer.
All I set was the voltages as per the trojan guide for the L16 batteries.
Not sure about end amps I do not recall seeing that when I setup and fired up the regulator.
I have not been able to find absorb times from any trojan websites or resellers.
Just spoke to the trojan shop I buy from and they said there is no set time for absorb.
Any suggestions as to the best approach?
Russ

[Westbranch]

got this reference by googling 'Trojan battery Absorb time'


US BATTERY CHARGING RECOMMENDATIONS - Trojan ...
www.trojanbattery.com/.../U.S.%20Battery%20Charge%20Profile%20Fu...
Notes: Charge time from full discharge is 8-12 hours. Absorption charge time is determined by the battery but will usually be "3 hours at 2.40 volts per cell.

[russ_drinkwater]

I only have 20% discharge overnight. When i try the link it comes up at the trojan website and says page not found!
So 3 hours of absorption for the bank each day.
Can I/or will the classic have the absorb times stored so I can retrieve that info?
Mine have not been updated.

[russ_drinkwater]

Did a search and found what I assume is the link and downloaded the pdf.
Will have a look today.
Thanks Russ

[Resthome]

I believe the default absorb time on the Classic is 2 hours IIRC. I believe the settings are right next to the Volts menu and called CHG Time. I'm not near a Classic at the moment but I believe this will be located under the Charge menu.

End Amps by default is set to zero or off. The WBjr has to be connected and set up for this to work correctly.

[russ_drinkwater]

Had a read today John.
I have set the absorb to 3 hours and it was default at 2 hours.
No whizbang jnr connected as yet.
End of the month it should all be a goer.

[sigp2101]

Had a read today John.
I have set the absorb to 3 hours and it was default at 2 hours.
No whizbang jnr connected as yet.
End of the month it should all be a goer.

So how does CC knows when to start with 2 hours charging interval. Do we need to specify that time? 11:00 AM to 13:00 PM for example.
I thought it would be automatic process, whenever there is enough sun on the sky. I am total beginner in this.

[Vic]

So how does CC knows when to start with 2 hours charging interval. Do we need to specify that time? 11:00 AM to 13:00 PM for example.
I thought it would be automatic process, whenever there is enough sun on the sky. I am total beginner in this.

For Solar charge modes,  at least,  the Classic begins each day charging batteries in Bulk,  Unless a number of Skip Days have specified.

The Bulk stage continues,  until the Absorb voltage setting is reached   This is when the Absorb stage begins,  and the Absorb timer (another setting)  begins to count down.   When the Absorb timer reaches the end of the time that has been set (that is,  reaches 00:00),  the Classic transitions to Float,  which keeps the batteries charged,  until there is too little input power (usually from the PVs).

The Classic does come from the factory with  generally-safe settings (Default settings) for Lead Acid batteries,  but one should set voltages and times as recommended by the manufacturer of  YOUR batteries.

There are some fine details that can change some of the above,  but this is the general nature of the Classic operation.

FWIW,   Vic

[BioPower]

When you get the Whizbang connected watch where the amps going into the batteries stops decreasing. Then set that as your end amps, still leave the 3 hours there but if you are only lightly discharging the end amps will come up a lot sooner than that.

[sigp2101]

So how does CC knows when to start with 2 hours charging interval. Do we need to specify that time? 11:00 AM to 13:00 PM for example.
I thought it would be automatic process, whenever there is enough sun on the sky. I am total beginner in this.

For Solar charge modes,  at least,  the Classic begins each day charging batteries in Bulk,  Unless a number of Skip Days have specified.

The Bulk stage continues,  until the Absorb voltage setting is reached   This is when the Absorb stage begins,  and the Absorb timer (another setting)  begins to count down.   When the Absorb timer reaches the end of the time that has been set (that is,  reaches 00:00),  the Classic transitions to Float,  which keeps the batteries charged,  until there is too little input power (usually from the PVs).

The Classic does come from the factory with  generally-safe settings (Default settings) for Lead Acid batteries,  but one should set voltages and times as recommended by the manufacturer of  YOUR batteries.

There are some fine details that can change some of the above,  but this is the general nature of the Classic operation.

FWIW,   Vic

Hi Vic,

Trojan specifies for their T-105s
Bulk at 44.5V,
Float 40.5V, and
EQ too be 48.6V for 36V battery bank configuration.
How do I setup classic accordingly when Classic 150 only has Absorb and Float.

[Vic]

Hi sigp2101,

Very few Solar CCs have a Bulk voltage setting.   So,  would set the Absorb voltage to 44.5 V.

Good Luck,  Vic

[sigp2101]

Hi sigp2101,

Very few Solar CCs have a Bulk voltage setting.   So,  would set the Absorb voltage to 44.5 V.

Good Luck,  Vic

OK, what should I set my absorb time to be then? 1 hour, 2 hours or else?

Thanks!

[Vic]

Hi sigp..,

The required Absorb for the battery depends upon how deeply-discharged the battery happens to be.   This is a variable.

End Amps from the Classic might be able to do a good job managing the end of Absorb,  but,  without the WBjr and a Shunt,  the Classic's EA function  (where Absorb can be ended by the current that the CC providing to the battery AND any loads)  will use all of the current being provided to the battery,  and all loads on the battery  (inverter,  and any direct DC loads).

If your loads on the battery are fairly constant during the time that the Classic is near the end of Absorb,  or if the loads are fairly constant,  and a larger load is intermittent,  CC EA (without WB & Shunt),  can still work fine.

The EA function relies on the fact that as batteries become fully-charged,  the amount of current that the battery needs tapers.  When this tapering battery current diminishes to a value where the rate of change is quite small,  Absorb can be terminated.

You can set a Maximum Absorb time in the Charge> Time menu.   This max time will end the Absorb,  even if the EA current value that you have entered in the Advanced menu has not be been reached.

With Flooded batteries (FLA),  the SGs can be checked,  and any small error is the EA setting can be compensated for by changes in Absorb voltage.

The Shunt + WBjr is an inexpensive option for the Classic,  and seems to me to be well worth the small additional cost.   This option will allow a more accurate termination of the Absorb stage,  using Shunt EA.

This might be a bit too much detail at this point ...

FWIW,   Vic