Hi there,
Thanks for reaching out—and I’m sorry for the hassle.
Yes, every UDPOWER unit is QC-tested before shipping (safety, input/output, and functional checks). That said, solar setups can vary a lot, and third-party panels are the most common source of charging issues due to connector/polarity/voltage mismatches.
To help you fast, could you share:
The brand & model of your solar panel(s)
A photo of the spec label on the panel (showing Voc/Vmp/Imp)
Which cable/adapter you used (e.g., MC4→DC plug/XT-style), and which port you tried on the S1200
Your order number.
Quick checks you can try now:
Verify panel specs vs. the S1200’s DC input specs. If the panel’s open-circuit voltage (Voc) is outside the allowed range, the S1200 won’t start charging.
Direct sun test: point the panel directly at the sun at midday; wipe dust; avoid glass/mesh; disconnect any USB regulators.
Cable & polarity: ensure positive/negative aren’t reversed; avoid step-up/step-down controllers between the panel and S1200.
One panel first: test a single panel alone (no series/parallel).
Wall-charge sanity check: plug into AC wall charging for a few minutes to confirm the input system is responding (helps isolate whether the issue is solar-side).
Important note: we don’t recommend third-party solar panels because some have incompatible voltages, non-standard wiring, or built-in controllers that block MPPT handshakes. Once you share the panel brand/model, I’ll confirm compatibility and the correct hookup for your S1200.
If anything looks off after that, we’ll take care of you.
Best regards,
UDPOWER Support