Renogy 4x100W Panels w/ MPPT 40A || to a AmpereTime 40A Charger

[Jorge33165]

Planning to use Renogy 4x100W Panels w/ MPPT 40A charger in parallel to an AmpereTIme 40A 110V AC charger.
Not sure why, but Renogy customer service is telling me that it can damage the devices.
I'm not sure on this... Can someone comment pls?
Regards,

 

[time2roll]

Multiple charging sources are generally not an issue. As long as the system is designed to collect 80+ amps all will be fine.
(although the controller will never go 40 amps with those panels)

 

[Jorge33165]

Multiple charging sources are generally not an issue. As long as the system is designed to collect 80+ amps all will be fine.
(although the controller will never go 40 amps with those panels)

I assuming 40A from the AC charger + 400W Solar Pannel /12V=33A=>73A max.... The problem is not the current but the devices themselves.

Below is AmpereTime answer:
Ampere TimeHello Jorge, You can use different charging methods at different times, but not at the same time. Such as you are using a charger, then if you need to charge the battery through the solar panels(with the controller), pls make sure to shut off the charger and then connect the battery to the controller. DO NOT RUN TWO CHARGING METHODS AT THE SAME TIME. Or the current may flow back into the controller/other devices and damage the controller/other devices.

 

[time2roll]

I assuming 40A from the AC charger + 400W Solar Pannel /12V=33A=>73A max.... The problem is not the current but the devices themselves.

Below is AmpereTime answer:
Ampere TimeHello Jorge, You can use different charging methods at different times, but not at the same time. Such as you are using a charger, then if you need to charge the battery through the solar panels(with the controller), pls make sure to shut off the charger and then connect the battery to the controller. DO NOT RUN TWO CHARGING METHODS AT THE SAME TIME. Or the current may flow back into the controller/other devices and damage the controller/other devices.

I understand what AT says. However this is just chasing the ghost of the boogie man. Never going to be any damaging flow back.
Otherwise every time a charger dropped to float and the battery voltage was a bit higher there would be damage.

 

[Jorge33165]

My concern is that the Solar Controller generates some high voltage spikes (transients, only milliseconds but enough to cause damage) that can go beyond the limits of the charger, worst if the battery circuit is open by the BMS.

 

[Jorge33165]

A silly answer from Ampere Time:
Hello Jorge, Different charging methods may have different charging modes and parameters, which may lead to damage to the charging device and is also not good for the battery. If two charging modes are used at the same time, which charging device should be based on by the BMS to determine whether the output voltage is appropriate?