New Issue: Random Overtemp error and System Shutdown

Dual Input, 120/240, stainless steel form factor design for unsurpassed surge capability
Post Reply
HwnVoltge
Forum Member
Posts: 12
Joined: Sun Jan 12, 2020 5:45 pm
My RE system: 2x Radian 8048A, Master-Slave
4x FM-100 300VDC
2x GS LC
1x FNDC (disconnected)
2x BlueIon 2.0 16kWh
1x Kohler RDT ATS

New Issue: Random Overtemp error and System Shutdown

Post by HwnVoltge » Fri May 15, 2020 9:52 pm

(edited for clarity)
Hi,

We have a system:
2x Radian 8048A, Master-Slave
4x FM-100 300VDC
2x GS LC
1x FNDC (disconnected), using battery sense voltage wiring instead to CC
2x BlueIon 2.0 16kWh
1x Kohler RDT ATS

System is operating in off-grid and has done so for about five months. Today the power shutdown. The Mate3s event log says an overtemp error. It appears both inverter transformers were at 125C when the shutdown occurred. The system was only outputting 8kW for about 3 hours prior to the event, there was a momentary surge to 14kW for about 38 minutes before the overtemp shutdown. No additional loads were turned on which would have caused the surge so the thought is maybe there was a short. However, after the overtemp cleared, both inverters came back online on their own and a 12kW surge resumed for 3 minutes and then dropped down to 8kW until that load was turned off a few minutes later.
What I don't know is why the surge occurred or how to check that.
I am also not sure why 14kW would overtemp the transformer when it's not maxing out the inverters combined output of 16kW unless maybe it was an unbalanced pull?

The load that was running was a heatpump for a pool. It was manually switched on about 2.5h prior to the surge event and after the inverters resumed operation when the temp dropped the heatpump resumed but was then manually switched off out of concern of the power off event.
I should mention the batteries were at 100% when the heatpump was switched on and the majority of the 8kW load was carried by the PV array with the battery fluctuating between 95% and 100% up to 30 minutes before the surge, 2.5h since the heatpump was switched on, when it had dropped to 90% and at the time of the surge it was at around 86%.
Last edited by HwnVoltge on Sat May 16, 2020 1:25 am, edited 4 times in total.

fcwlp
Forum Guru
Posts: 345
Joined: Wed Jan 22, 2020 9:40 am
My RE system: GS8048A, FM80 w/3,600 W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed
I also install and maintain grid-tied and off-grid systems, details will be given for these system if required
Location: 80 miles NE of Phoenix at 5500'

Re: New Issue: Random Overtemp error and System Shutdown

Post by fcwlp » Fri May 15, 2020 10:30 pm

The Radian will give an over temp error when the transformer is >125C, so it looks like you had a valid error.

The Radian output is de-rated above 25C (77F). What is the ambient temperature of the inverter room? At 50C (122F) the output is de-rated to 6kW.

You may want to have your HVAC take a look at the heat pump. Did the heat pump actually start running? Start up current on the heat pump should last <<1 second.

HwnVoltge
Forum Member
Posts: 12
Joined: Sun Jan 12, 2020 5:45 pm
My RE system: 2x Radian 8048A, Master-Slave
4x FM-100 300VDC
2x GS LC
1x FNDC (disconnected)
2x BlueIon 2.0 16kWh
1x Kohler RDT ATS

Re: New Issue: Random Overtemp error and System Shutdown

Post by HwnVoltge » Sat May 16, 2020 1:06 am

Oh I know the error was valid, I'm not disputing that I am disputing how it came about and potential things to investigate as to the surge.

I said it's random because the heatpump has been run for much longer times previously and it never had this overtemp error or surge. The system has had higher load usage and therefore higher inverter output than 8kW continuous for an equal amount of time and still had no overtemp error. It has not surged to 14kW before, I believe the highest recorded was 9kW.
The heatpump is for a pool and is manually switched. It was switched on around 3 hours prior according to load data and was running constantly for that time period, load was continuous around 8kW for those 3 hours until it did the surge to 14kW for 38 minutes before the overtemp.
Inverter location is outside in a covered area away from direct sun so ambient temp today would have been high 70sF as that was the air temp outside.

Either way, I'm going to hook up a logger to the feed going to the heatpump and run the pump again and see if the pump is related to this surge as it could be the heatpump going bad, it is an older unit.

pss
Forum Czar
Posts: 500
Joined: Mon Jul 24, 2017 8:40 am
My RE system: 8330 watts in three strings, Flexmax 60 x 3, Radian 8048A, GSLC load center, Mate 3S, Hub 10.3, FN-DC and 900 Amp, 48V Trojan T105-RE battery bank.

Re: New Issue: Random Overtemp error and System Shutdown

Post by pss » Sat May 16, 2020 7:18 am

If I may, what is the capacity of your pool heat pump in btu's? What is the size in HP of the pool's pump. What is the capacity of the pool? What is the water temperature without the heat pump and how much are you trying to raise it to?

Heat pumps take a lot of electricity to run, more so than a solar pool heater or LP pool heater.

fcwlp
Forum Guru
Posts: 345
Joined: Wed Jan 22, 2020 9:40 am
My RE system: GS8048A, FM80 w/3,600 W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed
I also install and maintain grid-tied and off-grid systems, details will be given for these system if required
Location: 80 miles NE of Phoenix at 5500'

Re: New Issue: Random Overtemp error and System Shutdown

Post by fcwlp » Sat May 16, 2020 11:04 am

HwnVoltge wrote:
Sat May 16, 2020 1:06 am
Either way, I'm going to hook up a logger to the feed going to the heatpump and run the pump again and see if the pump is related to this surge as it could be the heatpump going bad, it is an older unit.
It looks like you may be on the right track. Being off-grid I am sure you are aware of any 6kW loads that could turn on. I would also be listening to the heat pump, if it is the issue I expect the sound will change.

HwnVoltge
Forum Member
Posts: 12
Joined: Sun Jan 12, 2020 5:45 pm
My RE system: 2x Radian 8048A, Master-Slave
4x FM-100 300VDC
2x GS LC
1x FNDC (disconnected)
2x BlueIon 2.0 16kWh
1x Kohler RDT ATS

Re: New Issue: Random Overtemp error and System Shutdown

Post by HwnVoltge » Sat May 16, 2020 2:54 pm

fcwlp wrote:
Sat May 16, 2020 11:04 am
HwnVoltge wrote:
Sat May 16, 2020 1:06 am
Either way, I'm going to hook up a logger to the feed going to the heatpump and run the pump again and see if the pump is related to this surge as it could be the heatpump going bad, it is an older unit.
I would also be listening to the heat pump, if it is the issue I expect the sound will change.
Good idea, thanks

Post Reply