RENTECH VM-3000 and RENTECH 200AH LiFePO4

[DarrylHodges]

Hi all,

I recently purchased a RENTECH branded VM-3000 24V 3KVa inverter and also a 200AH 24V LiFePO4 rack mounted battery.
I also purchased a 125A battery disconnect, because that's what every one said I also required.
My use of this system is purely as a big UPS. There is no Solar (Yet) and I'm using Eskom to provide load and to charge when low.

So I installed everything into a small moveable Rack (Audio type 19"  Rack) - works just perfectly.

On the RENTECH website there was no real documentation and the sales at Rentech are the same.
I did find a rentech setup document on another providers website - Wierd!!! It provides the VM-3000 setup guide.

So, i've setup the inverter to "User" Battery, current charge = 27.6V and the floating charge 27.6V.

It has been charging now for 3 full days, and the inverter still showing "Charging" under the battery. There is 0 load currently.
The fans are not on at all, and randomly come on when charging if the temp goes > 40. They turn on 100% and noisy as hell.
 

Is there anyway to have the fans run 100% of the time, even at a 10-15% speed, in order to keep the air flow moving?
Is there any setting for possibly changing a "Fan Curve"

If this Inverter is going to be so loud during charging, would it be possible to install the battery outside, on my balcony, in a cupboard?
It should never go below 0 degrees - Do you think this would be workable or a stupid idea? I'd rather ask then learn a hard answer the wrong way.

Thanks

Darryl
 

[Coulomb]

On 2022/05/02 at 8:52 PM, DarrylHodges said:

Is there anyway to have the fans run 100% of the time, even at a 10-15% speed, in order to keep the air flow moving?
Is there any setting for possibly changing a "Fan Curve"

I don't believe that there is,  but I've never owned or looked inside a Value Model (any of the VM series). My understanding is that one of the compromises made to increase the "value" is that they use cheap fans that are either on or off, nothing in between.

It might be possible to replace the fans with quieter versions that have the extra input for PWM control of the speed, and use an Arduino or even a 555 timer chip circuit to drive that input at about 30% PWM (that seems to be the "just ticking over" speed). But when the firmware turns off the fans, it will cut the power, so you'll have to provide another source of 12 V power, and use the power from the inverter as a digital input to some simple logic or use diodes to "diode OR" the inverter power into the PWM input of the fan(s).