SPD3303X-E Parallel Mode Output Question

[low_noise]

Greetings,

I have a SPD3303X-E (hardware version 3.0, firmware 1.01.01.02.07R2) that has been modded as a SPD3303X.  When in Parallel mode, CH1 and CH2 current output readings do not seem to track each other.  The behavior I was anticipating (based on youtube review) is that Channel 1 and Channel 2 readings would be the same, contributing equally to the total output.

Instead, the behavior I am observing is that Channel 2 will have near zero current output up until channel 1 current output has reached it's max.  Once channel 1 has reached its max current setting, then channel 2 reading will increase until the max current setting.

Does anyone happen to know if this is normal behavior for the more recent firmware and/or hardware revisions?

Thanks in advance

[tautech]

Welcome to the forum.

In the earlier HW this is normal.
From the Quick Guide P15
https://int.siglent.com/u_file/download/22_11_25/SPD3303X_QuickStart_E02A.pdf
CH1/CH2 Parallel mode
Instruction
In the parallel mode, CH1 and CH2 are linked internally into one channel which is controlled by CH1.
Its output current value is twice as much as the single channel.

In later HW the OSD has been changed for the better and provides totalled output values but unfortunately we cannot install the later FW that goes with it.
More info and a pic of the latest OSD here:
https://www.eevblog.com/forum/testgear/siglent-spd3303x-and-spd3303x-e-power-supplies/msg5548861/#msg5548861

[low_noise]

much appreciated, thank you for the explanation and the quick response.