Solar Diehl AKO Platinum Inverter 4300S Help

[Graham Smith]

Good evening all - I used to be a member of this forum ages ago, but couldn't work out what my username and old email address was, so decided it was easier to register again.

Many years ago, (2012?) at home I had installed a 4kw system - 20 panels with a Diehl AKO Platinum Inverter 4300S. We had it installed just six days before the really good FIT rate reduced by half. All was good until yesterday.

As we had some spare space on the roof, a while ago, I took the decision to put another 8 panels up and get another inverter and run them as two totally separate systems.

OK, so I know I'm not really supposed to do this, as I'd need permission to feed it back into the system, but as I'm not actually charging for the excess power I produced, I figure no-one is going to worry that much.

My panels are identical to the old ones, and my new inverter is a Diehl AKO Platinum Inverter 3800S. I decided to go for the smaller inverter as I don't have as many panels.

Both systems have separate DC isolators, separate AC isolators, separate generation meters. They really are completely separate.

As I say, all was fine until yesterday, but (foolishly), I connected an ethernet cable between the two inverters to link them with our solar-logging device, and that's where my problems have started.

The original inverter now shows an error of 257 which I understand is some sort of comms error.

Is there any way of doing a factory re-set on the inverter to see if that will clear the error, or failing that if it's beyond help, there's a guy selling second hand units on eBay which is pretty tempting as they're a fraction of the price of a new one.

I'd really appreciate any help/advice anyone is able to give me, as I've now got a system which isn't producing anything!

Many thanks in anticipation.

 

[Markc]

Hi Graham,

What are the LEDs doing. Red flashing, red constant etc?

Are you able to access the service "hidden" menu on both inverters? Able to read additional fault codes and events?

Have you set numbers of inverters on the network as 2? Number of participants should be 3 with a monitor.

Error code 257 shouldn't be a blocking code so by re-starting the inverter/s without the network cable connected should re-establish generation mode. Fully shutting off the DC and AC and leaving for 5 minutes and then re-starting again without the data cable in place to either inverter or monitor.

I would avoid buying the second hand unit for this fault. Its an over kill. Also some units had a recall on them for a faulty power component some years ago. Diehl were great at the time in sending out a replacement unit and returning the old unit. About a four day turn around in total which was great customer service. However I know some failed units were never returned or collected. Some of these may now be in the market place and will not be under the Diehl 10 year warranty. Without a serial number of the second hand unit there is no way of knowing its use.

M

 

[Graham Smith]

Hi there. Thanks so much for your help.

I phoned up their technical support, and they were REALLY helpful.

It turned out that somehow phase balancing had been turned on when I connected the two units together, and it was this that was causing the error.

All seems to be fine now.

But if you're a regular visitor to this site, I'm still trying to get to grips with the DC wiring on our system, so I'll message you again in a few days with another question if that's OK?

Best regards

 

[Mark42]

I did a similar install at my house at the same time - before the FIT rates were cut - an icy February I remember was! Horrible conditions on the roof but it had to be finished in a couple of days.
I had a rural split phase supply so installed two separate 4kW systems, one for each phase.
I run the MV dc from the panels underground on a 4 core 10mm swa to Diehl inverters in the house 150m away, to avoid the losses and cable cost of sending LV ac that far. It’s worked a treat so far ....