Configure MPPT with Renogy 100ah

[teddysx3]

Hello guys,

Going to start configuring my MPPT soon, and I have a few question.

I just read a bunch on about the Renogy how they don't have a float and eq voltages. They recommend for absorption 14.4, and for float and eq, either 14.4 (the same as absorb) or set to 0. I'm going to go with Will's advice in one of the threads hear on the forum.

Absorb :14.4
Float: 13.6
Eq: 14.4

If anyone has a Renogy or has a comment on the above, would love to hear your opinion.

Second part it, I read about Bulk charge, and Absorption is after it. At the same time, i read that bulk=absorption, their are the same. Inside the Victron MPPT, I don't see Bulk option to set the voltage, there are only 3 of them: Absorb, Float, Eq.

So how should I understand this?

Also I see people setting in expert mode absorb time to 1h. If I understand this correct, the absorb will run for 1 hour and stop, but when I have not configured the "bulk" because there is not option for it, how is the battery going to be charged, for 1 hour or until it gets to 14.4. A little confused here!

Thanks guys!

 

[mikefitz]

What battery type do you have and what controller?

I agree the terms used by Epever are confusing.

The terms 'boost' and 'absorption ' voltage is the 'target voltage' that the charger will attempt to reach during the 'bulk' phase of charging.
During the bulk phase the majority of energy is replaced in the battery .

Once the target volts is reached the controller enters the 'boost duration ' or 'absorbtion' period. During this period the voltage is held constant at the 'target voltage'. The battery will accept a reducing current during this phase.

Once the absorbtion phase is completed the charger provides a constant float voltage to the battery.

For a 12v lithium battery any voltage over 13.8 volts for the 'target volts' will charge the battery. The lower the voltage, the less stress on thebattery and perhaps longer life. Victron now suggest 14.2 volts.
The absorbtion period, ( boost duration) need not be long where the charge current is low compared to battery capacity, for most hobby systems this period could be set to zero. However if the battery has unbalanced cells having time to carry out balancing may be useful.

The float voltage set at battery rest volts, around 13.4 volts, will be adequate for most applications. If the solar power is powering significant loads during the solar day, having a slightly higher float could be used.

Equalisation is a condition where a higher voltage than normal is applied to the battery at intervals, perhaps every month. This is only needed for flooded lead acid batteries. When lithium batteries, or AGM lead acid batteries are used, this feature is not needed.

If the batteries you have are Renogy AGM batteries then a charge voltage , 14.4 to14.8, absorbtion period 2 hours or longer, float 13.8.

Mike

 

[teddysx3]

What battery type do you have and what controller?

I agree the terms used by Epever are confusing.

The terms 'boost' and 'absorption ' voltage is the 'target voltage' that the charger will attempt to reach during the 'bulk' phase of charging.
During the bulk phase the majority of energy is replaced in the battery .

Once the target volts is reached the controller enters the 'boost duration ' or 'absorbtion' period. During this period the voltage is held constant at the 'target voltage'. The battery will accept a reducing current during this phase.

Once the absorbtion phase is completed the charger provides a constant float voltage to the battery.

For a 12v lithium battery any voltage over 13.8 volts for the 'target volts' will charge the battery. The lower the voltage, the less stress on thebattery and perhaps longer life. Victron now suggest 14.2 volts.
The absorbtion period, ( boost duration) need not be long where the charge current is low compared to battery capacity, for most hobby systems this period could be set to zero. However if the battery has unbalanced cells having time to carry out balancing may be useful.

The float voltage set at battery rest volts, around 13.4 volts, will be adequate for most applications. If the solar power is powering significant loads during the solar day, having a slightly higher float could be used.

Equalisation is a condition where a higher voltage than normal is applied to the battery at intervals, perhaps every month. This is only needed for flooded lead acid batteries. When lithium batteries, or AGM lead acid batteries are used, this feature is not needed.

If the batteries you have are Renogy AGM batteries then a charge voltage , 14.4 to14.8, absorbtion period 2 hours or longer, float 13.8.

Mike

Hey,

Sorry I did not say what type of battery I have. It the Renogy 100ah Lithium self heating model.

So I still don't get from your answer, you say set absorption to 0, in the Victron MPPT, where do you actually set it to 14.4 to charge the batteries? I think the absorption is the same as the bulk, and setting absorption to 14.4, will charge the batteries at 14.4, from what I was able to read. The MPPT doesn't have any other setting to set the "bulk" or "target voltage" as you describe them.

The float could be set to a 13.4 or 13.6 as you suggest, still I read it's not needed for lithium batteries, as well as the equalization option.

But setting them as 0 is correct? or setting them to the absorption voltage is more correct? 14.4.

Renogy suggested me to set float and eq to 0, because it was not needed for their batteries, which again I know they are a re brander company, and just slap on these settings. And if you suggest setting the absorption to 0, then all my settings are going to be 0 :D

 

[mitchofcanada]

Pretty sad renogy doesnt have this on their website. My Amphere Time 24v 100ah, had a great manual that came with the unit however the website does not show the flat/absorption settings also.
It does show Nominal Voltage 12.8 for renogy. however the Float for my Ampheretime 24V was 27.6 or 13.8V.
So is the renogy Nomimal/Float Voltage actually 13.8v?