pairing Bluetti EP500 Pro (EP500P) all in one to REC 350 TP2S72 Panels

[Kapow_Network]

After mutiple setbacks I'm going to try my best to document my journey
pairing Bluetti EP500 Pro (EP500P) all in one lithium battery to REC 350 TP2S72 Panels.

Note: Bluetti offers their own panels but I felt they were overpriced when I purchased the Bluetti EP500P on kickstarter.

First problem was getting proper mounts for the panels I bought.
I more or less created them myself.
They are up on a trailer roof and perhaps I will create a seperate thread on that.
Ideally I'm going to keep this thread on point with diagnosing why the components do NOT seem to be pairing well together.
And hopefully, with the help of you all (as Bluetti support seems slow / limited) I can get this functional.

Overview:
2 REC 350 panels (700w total) are supposed to connect to the Bluetti which has an internal controller and came with a cable that splits up to allow 2x MC4 connections.
On the Bluetti's screen The 2x MC4 connections are represented by the words

DC1 Input Source
DC2 Input Source

Main problem: after using MC4 connectors / wire to connect the panels, the Bluetti LCD panel shows international "power" buttons for DC 1 and DC2.
When I hit the buttons nothing happens.

Hypothesis:
Either the Bluetti's not working, or the panels aren't sending out current.

Sub-hypothesis, if the Bluetti is not working it could be because:
the 4 stranded wires representing DC1 (+ and -) and DC2 (+ and -) are cross-connected.

NOTE: Bluetti never labelled the wires beyond saying they were (+ and -) which is already obvious from them being red or black respectively.

I will try to soon post pictures or more pictures.
Open to any other guesses or hypothesis.
May take a day before I can get out the multimeter / take measurements etc.

Note: Bluetti does NOT seem to want to set up a videocall, but does seem to try to respond to emails.

I'd really like to get this working well before Christmas!

 

[Kapow_Network]

When I connnected the 2 REC panels they seemed to be working. But to test the Bluetti, I wanted to disconnect the panels from the Bluetti and check output. Bluetti so far has seemed interested in knowing what happening (which is comforting).

When I tried to check PV output on the cables it appeared no signal was going into the Bluetti.

In the evening (to ensure no load) I disconnected them from the Bluetti cable; and separated the cable from the Bluetti itself.

I verified output on one panel.

When I tried to verify output on the next panel, the plastic spanner (I think it came free with something but am not sure what) broke. Also, when I looked closely, it didn't appear to fit well. I saw some reviews saying that this might happen (eg - if the spanner came with some extra Renogy mc4 connectors I ordered, then maybe it only fits Renogy mc4 connectors ? not the connectors on the panels nor the cables I received w/t panels).

I now need to order a new spanner tool and/or figure out a way to work around the
each other and verify output individually.

NOTE: Once I get these disconnected, I am considering over riding the need for a "key".
This apparently can be done like this:

I may post a question about this elsewhere, but for all the trouble, I don't see the value of a key tool or "key".

 

[Kapow_Network]

Following up earlier I stated:
Hypothesis:
Either the Bluetti's not working, or the panels aren't sending out current.

Sub-hypothesis, if the Bluetti is not working it could be because:
the 4 stranded wires representing DC1 (+ and -) and DC2 (+ and -) are cross-connected.

NOTE: Bluetti never labelled the wires beyond saying they were (+ and -) which is already obvious from them being red or black respectively.

END QUOTE:
====
Current awareness:

It's working. PV power is showing on Bluetti.
I had rechecked my wires / connections. For sure on the second time they were tight (despite mods to the mc4 connectors as stated above).

BUT after plugging in the AC power, I thought to try to ADD the PV power.
Suddenly PV power seemed to work (whereas before on it's own it didn't appear to be recognized by the Bluetti EP500P.
This gave me hope that it might also work when I turned OFF the ac power.
IE - that perhaps it just needed this initially... Perhaps this is bad programming on their part?
So I unplugged the AC power to see if the PV power would still register.
It did.

Arguably problem solved. But I emailed Bluetti and asked if this is "normal" or an issue.
For me it's an issue because, without hooking up a generator etc, I'd like to just plug in the PV power and know the Bluetti will perceive it.

Later I'll try to unplug the PV, then replug it in without AC and see what happens.
For now I'm just happy it topped off without AC power.

Might be a delay in posting due to other issues / holidays.

 

[Kapow_Network]

PS - am hopeful that some day someone else with a Bluetti / EP500P might say if they've had a similar experience.
OR if they could use this thread to mention any quirks they have experienced.