Issue with old inverter

[Krusscher]

We have a solar panel system that was installed around 2000. I guess they have been having issues with it for a while and the old electrician would just hit the estop to reset what ever fault was occurring. Well its been faulted ever since I got here and I am now getting around to looking at it. The problem right now is that the fault light is on but the lights that are supposed to flash the code are not doing that. I know they may be burnt out but I checked them with my multimeter and I can't see the voltage changing at all like its turning on and off. As you can see in the pictures it looks like it may have had issues with moisture which may have caused something to fail.
This is such an old invertor I am wondering if it would make sense to just replace it with something similar or if it is worth it to trouble shoot what is going on. If I do decide to replace can someone recommend a brand/model. In an old email my boss sent me someone from the POCO suggested installing microinverters that tie 2 modules together at a time as it would be safer then dealing with 480v of DC but I honestly think that is a bit much extra work.

 

[jaggedben]

Wow a Trace 3 Phase inverter.
The nice thing about Trace is that they were old-fashioned in the sense of being able to replace parts to repair. But you'd need a source for the parts. Probably easier to find a new Fronius or an SMA replacement.

I'd want the solar module specs to double check compatibility.

The fault could definitely be a ground fault, or more than one. In which case troubleshooting could be a pain, and the problem might reoccur.
Possibly a reason to overhaul the wiring and go the microinverter route anyway. With these modules you might be able to connect two modules to a micro in series but again I'm not sure without module specs.

 

[Krusscher]

Wow a Trace 3 Phase inverter.
The nice thing about Trace is that they were old-fashioned in the sense of being able to replace parts to repair. But you'd need a source for the parts. Probably easier to find a new Fronius or an SMA replacement.

I'd want the solar module specs to double check compatibility.

The fault could definitely be a ground fault, or more than one. In which case troubleshooting could be a pain, and the problem might reoccur.
Possibly a reason to overhaul the wiring and go the microinverter route anyway. With these modules you might be able to connect two modules to a micro in series but again I'm not sure without module specs.

 

[synchro]

Just a guess, but the open frame transformers at the bottom may have been degraded by water incursion, eventually resulting in an internal fault.

 

[tortuga]

Often they can be repaired, you might look for a inverter repair tech in your area.
You can find lots of info on those old trace/xantrex inverters online:
https://shop.solardirect.com/pdf/dated/clearance-xantrex-pv10208.pdf

 

[pv_n00b]

Since it was installed in 2000 the system has been in operation for 23 years and is at its end of life. I think it would be hard to justify the changes that would have to be made to connect the old modules to a new inverter. If you can find an NOS trace inverter somewhere then go for it, otherwise I would recommend retiring the system and installing a new one.
The fact that the Trace lasted this long is a testament to the engineering that went into it. You just don't find that any more.

 

[ggunn]

Since it was installed in 2000 the system has been in operation for 23 years and is at its end of life. I think it would be hard to justify the changes that would have to be made to connect the old modules to a new inverter. If you can find an NOS trace inverter somewhere then go for it, otherwise I would recommend retiring the system and installing a new one.
The fact that the Trace lasted this long is a testament to the engineering that went into it. You just don't find that any more.

The modules could be worth keeping; if their Voc and Isc values are reasonably close to spec and they don't look damaged, why throw them away?

 

[Krusscher]

Since it was installed in 2000 the system has been in operation for 23 years and is at its end of life. I think it would be hard to justify the changes that would have to be made to connect the old modules to a new inverter. If you can find an NOS trace inverter somewhere then go for it, otherwise I would recommend retiring the system and installing a new one.
The fact that the Trace lasted this long is a testament to the engineering that went into it. You just don't find that any more.

After talking to the old electrician that worked at the college 5 years ago it sounds like it was ready to give up the ghost awhile ago but he just kept resetting it when it would fault.
I don't think they will go for replacing the modules but I guess the PUD will cover some cost with the system. I have no experience with solar so I am not quite sure where to start with testing panels to see if they are good or not.
Do you think it would be hard to find a replacement inverter that would work with the current setup?

 

[jaggedben]

Do you think it would be hard to find a replacement inverter that would work with the current setup?

Probably not.

I think Fronius or SMA are still likely a good bet. It's been years now since I've done this, but I believe both have inverter sizing tools available online. So you tell it what the array is and see what they spit out.

These inputs should be sufficient:
Grid voltage/phases
Solar module model
Modules per string (22)
Strings (6)

Note that in your diagram all strings are combined so all the amps go to one input. That might be the sticking point, but you might be able to divide them up and pull new wire to an inverter with multiple inputs.

All that said, if you have no experience with solar I'm worried about what else you don't know. Is asking a solar company to quote this not an option?

 

[Krusscher]

All that said, if you have no experience with solar I'm worried about what else you don't know. Is asking a solar company to quote this not an option?

I too am worried about that honestly. But I guess before I got here they were planning on having the electronics class try to fix it... I don't know what that means but I am also a little worried about that and they haven't really seemed that interested in doing it so I figured I would see what I could find out about it before they let any college kids touch it lol.

I figured replacing the inverter wouldn't be a big deal but it appears there might be more to it then I thought. The problem with getting contractors is that we have to go through a small works roster and it ends up doubling the price pretty much.

 

[jaggedben]

Yeah I don't think you really want college kids touching 400VDC that can't be turned off. But it might be worthy of the class to research PV design and select an inverter.

 

[BillK-AZ]

A Fronius Symo Advanced 15.0-3 480 will nicely replace the inverter and transformer. The AC wiring will have to be upgraded since the Max. continuous output current 277 V increases to 18,0 A. The Source Circuit Combiner boxes can not be used with a transformerless inverter. I replaced one of these Trace 10 kW inverters with a Symo 10 kW 208V in 2015, no problems since. You really do not want the Trace transformer powered all the time, it runs hot.