170 likes | 488 Views
The following slides explain the Ground Fault Detection and Interruption (GFDI) system in a FRONIUS IG inverter. Please note that each slide is provided with sound. Please switch on your loudspeakers and press the keys at the bottom of each slide to proceed.
E N D
The following slides explain the Ground Fault Detection and Interruption (GFDI) system in a FRONIUS IG inverter. Please note that each slide is provided with sound. Please switch on your loudspeakers and press the keys at the bottom of each slide to proceed. FRONIUS GFDI
FRONIUS Ground Fault Detection and Interruption What is a ground fault? Installation instructions Contact FRONIUS tech support Troubleshooting FRONIUS GFDI
What is a ground fault? NEC definition: An unintentional, electrically conducting connection between an ungrounded conductor of an electrical circuit and the normally non-current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth. + = L1 L2 ~ GND - Main page Installation instructions FRONIUS GFDI
Installation instructions • Connect PV/DC module frame ground to (5) and AC ground to (1). • Do not connect ground to the DC negative at any point This is already done inside the FRONIUS IG. !!! Connecting the ground to DC negative prior to the inverter will circumvent the GFDI protection system and the inverter will indicate a ground fault. !!! Main page Ground fault troubleshooting FRONIUS GFDI
AC/DC ground terminal + = L1 L2 ~ GND A - GFDI fuse Main page Previous page FRONIUS GFDI
A Ground fault troubleshooting Ground fault detection system operation: • DC negative is grounded through the 1 A GFDI fuse. + = L1 L2 • When the ground fault current exceeds 1 A, the ground fault fuse opens and the inverter shuts down with STATE Code: 434 ~ GND A - Main page 434 troubleshooting FRONIUS GFDI
STATE 434 troubleshooting Ground fault LED OFF Ground fault LED ON Main page FRONIUS GFDI
STATE 434: Ground fault LED ON STATE 434 with LED ON indicates that there is a ground fault on the PV module (DC) side of the system. • Follow steps below to locate the fault: • Check the 1A GFDI fuse. • If the fuse is not blown, the ground fault current is less than 1A. • Vice versa if the fuse is blown. Do not replace the fuse without following the steps below! • In both cases, remove the GFDI fuse from the fuse holder and using a multi-meter, measure the following DC voltages: • Between DC Positive terminal and Ground terminal V1. • Between DC Negative terminal and Ground terminal V2. Main page Continue… FRONIUS GFDI
State 434: Ground fault LED ON (continued) From the previous page, if V1 is approximately equal to V2 (±5%): • The ground fault could be a temporary fault caused by expansion/contraction due to temperature or other variations. • If the system does not recover and the problem persists (STATE 434 & V1 = V2), please contact FRONIUS tech support: V1 V2 If V1 is not equal to V2, then there is a ground fault in the system. Continue to next page… Previous page Continue… FRONIUS GFDI
State 434: Ground fault LED ON (continued) Consider the PV system shown: 3 strings of 4 modules each connected to a FRONIUS IG. Under normal conditions: Voc = 400 V V1 = 400 V V2 = 0 V When the GFDI fuse is removed, the voltages should divide approximately equally: V1 = V2 = Voc/2 Previous page Continue… FRONIUS GFDI
State 434: Ground fault LED ON (continued) Assume there is a ground fault on the rightmost string. Follow the steps below to locate the fault: • First, remove the GFDI fuse. (For a string inverter system with a common negative bus, remove all the GFDI fuses.) • Connect only one string to the inverter and measure V1 and V2. • Again, when there is no fault in the string V1 = V2 = Voc/2. • Repeat steps 2,& 3 for each string.Since there is no fault on strings 1 and 2, Voc is split equally between V1 and V2. Previous page Continue… FRONIUS GFDI
State 434: Ground fault LED ON (continued) When there is a fault in the string, Voc does not split equally.And, the ratio of V1 and V2 indicates the location of the fault along the string. For the system shown, the fault is located between modules 1 and 2.Therefore, V1 = 100 10 V V2 = 300 10 V Ratio of V1 and V2 is 1:3. Therefore the ground fault is located after module #1. For further assistance contact FRONIUS tech support. Previous page FRONIUS tech support FRONIUS GFDI
FRONIUS technical support For more information please don’t hesitate to contact FRONIUS technical support phone: 810 220 4414 fax: 810 220 4424 pv-us-support@fronius.com www.fronius-usa.com Main page FRONIUS GFDI