grounding of the aluminium frame of the pv panels?

Discussion about the FM100, FM80, and FM60 Charge Controllers

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solarman71
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My RE system: 6 panels POLY 240W BYD 240P6-30, FM60, 8 batteries TAB 95T deep cycle tubular plates 12v - 115Ah - C20 in 24 V configuration (24v-460Ah total), Clayton Power G3 Combi Inverter/Charger 24v-2300W-50A, Victron Energy BMV600 battery monitor, SSR 40A on AUX-Diversion SSR

grounding of the aluminium frame of the pv panels?

Post by solarman71 » Thu Jul 04, 2013 10:55 pm

Hello everybody,

I understood that the grounding is very important for the:

-charge controller;
-off-grid inverter;
-grid-tie inverter.

Can anyone comment what can happen if the charge controller and the off-grid inverter were to function without the grounding?

More than this - does anyone connect to the ground the aluminium frame of the PV panels? I noticed there is a hole in the frame of the panel with the grounding mark next to it.

My panels are mounted on top of the house, I am thinking that maybe this grounding of the aluminium frame can help in case of a lightning or something. I would appreciate any answers concerning this, as I have not found much info online on this topic.

Thank you.

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MyEnergyWarehouse
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Re: grounding of the aluminium frame of the pv panels?

Post by MyEnergyWarehouse » Fri Jul 05, 2013 7:13 am

Hello Solarman71,

As to your question, "Can anyone comment what can happen if the charge controller and the off-grid inverter were to function without the grounding?" I will leave that alone.

However, I will comment on the grounding question. All of our installations are well grounded! We connect all the panels, rails, EMT conduit and any other metal parts to a system ground. We use a UL listed grounding lug and copper wire. No WEEBS used either! This is installed per NEC 2011. We always connect this to two ground rods, 6 feet apart, per local code.

This may be more than most installers do. We consider a solar array as an electrical generating facility. As such, we want to make sure that we do everything that we can to avoid as much potential hazard to anyone as possible. If everything is working as it ought, this grounding is not necessary. But what if in 30 years, something malfunctions?

Remember, the purpose for a system ground is to take any "out of place" electrons to the ground in the most direct path with the least resistance. This is just as important whether the system is new, gets hit by lightning or if there is any electrical malfunction.

gww
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Re: grounding of the aluminium frame of the pv panels?

Post by gww » Fri Jul 05, 2013 1:25 pm

If you want to read about a million threads about grounding, look at the forum;
"Northern arizona wind and sun"
Good luck
gww

solarman71
Forum Whiz
Posts: 33
Joined: Tue Mar 12, 2013 12:44 pm
My RE system: 6 panels POLY 240W BYD 240P6-30, FM60, 8 batteries TAB 95T deep cycle tubular plates 12v - 115Ah - C20 in 24 V configuration (24v-460Ah total), Clayton Power G3 Combi Inverter/Charger 24v-2300W-50A, Victron Energy BMV600 battery monitor, SSR 40A on AUX-Diversion SSR

Re: grounding of the aluminium frame of the pv panels?

Post by solarman71 » Fri Jul 05, 2013 11:31 pm

Thank you so much for your comments!

TomSandy76
Forum Member
Posts: 10
Joined: Thu Nov 21, 2013 7:16 am
My RE system: 4 Grape Solar 250 watt panels:
Max System Voltage 1000V / 600V
Max Peak Power Pmax
250 W (-2%, +2%)


CEC PTC Listed Power

222.1 W


Maximum Power Point Voltage Vmpp

30.7 V


Maximum Power Point Current Impp

8.15 A


Open Circuit Voltage Voc

37.7 V


Short Circuit Current Isc

8.72 A

Module Efficiency (%)
15.4%


Temperature Coefficient of Voc

-0.128 V/ºC (-0.34% /ºC)


Temperature Coefficient of Isc

3.49x10-3 A/ºC (0.04% /ºC)


Temperature Coefficient of Pmax

-1.20 W/ºC (-0.48% /ºC)


FM 80
Midnight solar MNDC 250
8 6volt batteries:
US RE GC2H XC - 6 Volt Deep Cycle

5 Hour Rate / 193
10 Hour Rate / NA
20 Hour Rate / 242
100 Hour Rate /266
Min @ 25 Amps / 493
Min @ 75 Amps / 128
Min @ 56 Amps / N/A
Plates Cell / N/A
Length / 10-1/4" (260mm)
Width / 7-1/8" (181mm)
Height / 11-7/8" (302mm)

Re: grounding of the aluminium frame of the pv panels?

Post by TomSandy76 » Sat Dec 28, 2013 4:20 pm

MyEnergyWarehouse wrote:Hello Solarman71,

As to your question, "Can anyone comment what can happen if the charge controller and the off-grid inverter were to function without the grounding?" I will leave that alone.

However, I will comment on the grounding question. All of our installations are well grounded! We connect all the panels, rails, EMT conduit and any other metal parts to a system ground. We use a UL listed grounding lug and copper wire. No WEEBS used either! This is installed per NEC 2011. We always connect this to two ground rods, 6 feet apart, per local code.

This may be more than most installers do. We consider a solar array as an electrical generating facility. As such, we want to make sure that we do everything that we can to avoid as much potential hazard to anyone as possible. If everything is working as it ought, this grounding is not necessary. But what if in 30 years, something malfunctions?

Just curious, why no WEEBS?

Remember, the purpose for a system ground is to take any "out of place" electrons to the ground in the most direct path with the least resistance. This is just as important whether the system is new, gets hit by lightning or if there is any electrical malfunction.

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