SURGE PROTECTION OPTION

Transcription

1 Reliable Continuous Energy PV FOR TELECOM Installation Guide Gen 4 PVT Panels ENHANCED SURGE PROTECTION OPTION Manual Rev 4.4

2 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page IMPORTANT SAFETY INSTRUCTIONS ALSO READ THE COMPLETE SAFETY INSTRUCTIONS IN THE PVT INSTALLATION GUIDE WARNINGS: DANGER -- HIGH VOLTAGE During the installation of this product, you will be exposed to wires from the Solar PhotoVoltaic (PV) panel array which are energized with high voltage. The high voltage is present during all daylight hours. If a Combiner Box is wired in the system, turn all the Circuit Breakers in all the Combiner Boxes OFF before opening the Apollo PVT Cabinet doors. If a Combiner Box is NOT wiring in series with the PV Array, carefully disconnect the PV Array at the most convenient location and do not re-connect it until the work in the Apollo PVT Cabinet is complete and the doors are closed. This system is energized from multiple sources. In addition to the PV Array, the Battery also provides dangerous power to the Apollo PVT Cabinet. Disconnect the Battery after the PV Array is de-energized. 1 Warnings to Prevent Damage ALWAYS TURN THE BATTERY POWER TO THE T80HV CHARGE CONTROLLERS ON BEFORE TURNING ON THE PV INPUTS. ALWAYS TURN THE PV INPUT OFF BEFORE TURNING THE BATTERY POWER OR THE T80HV OUTPUT CIRCUIT BREAKERS OFF.

3 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page Photo of the Gen4 3X Panel with the Enhanced Surge Protection Option The components of the Enhanced Surge Protection Option are in the lower right and the lower left corners of the standard PVT panel inside the Yellow outline. The balance of the panel is identical to the standard product.

4 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page ENHANCED SURGE PROTECTION BLOCK DIAGRAM After a number of years of research, Apollo Solar developed a surge protection scheme which has proven to be effective in both laboratory and field tests. We employ multiple tandem stages of devices to limit the voltage which can reach the vulnerable circuits. The first protection element is a high current MOV in the Combiner Box. These fast acting can dissipate 70 KA and the fact that they are in the Combiner Box, away from the main cabinet, provides a good first line of defense against nearby lightning strikes. The second element is a 20KA MOV just inside the main cabinet. This device is selected to clip any incoming voltage spikes down lower than the heavy duty MOVs in the Combiner Box. The next element is a high current inductor used to slow down the rise time of the offending pulse. Finally, a Transient Voltage Suppressor can accurately clip the voltage to a safe level. APOLLO SOLAR - 4 STAGE ENHANCED SURGE PROTECTION FOR PV INPUTS PV ARRAY GROUND PV MODULE FRAMES STAGE 1 75KA MOVs CITEL DS72US-120G Wire loop threaded through each PV module frame for theft alarm. APOLLO COMBINER BOX PV ENERGY 75 to 160 VDC AT UP TO 50 AMPS This wire loop is in series with all SPDs in combiner boxes for MOV end of life alarm. THESE WIRES CAN BE 15M LONG RUN WIRES IN CABLE TRAYS RUN GND WIRE BACK TO OUR CABINET GND EQUAL POTENTIAL GROUND EARTH GROUND SYSTEM WITH RING OF GROUND RODS CONNECTED TOGETHER. EACH GROUND ROD CONNECTION MUST BE LESS THAN 5 OHMS. MULTIPLE PV INPUTS FROM INDIVIDUAL COMBINER BOXES. APOLLO 50A SPD ON EACH PV INPUT. APOLLO SOLAR PVT CABINET 48VOLT POSITIVE GROUND APOLLO 50 AMP SPD 20KA MOV 20KA MOV 10uH 50A COMMON MODE CHOKE STAGE 2: 20KA MOVs 5KA TVS 5KA TVS STAGE 3: 10uH 50A COMMON MODE CHOKEs 50A APOLLO T80HV MPPT CHARGE CONTROLLER 100A -48V POSITIVE GND POINT ALUMINUM CHASSIS GND STAGE 4: 5KA TRANSIENT VOLTAGE SURPRESSORS 48V OUT TO LOAD 40KA MOVs ON 48V LOAD

5 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page V 0 TANDEM DEVICES DISSIPATE ENERGY IN STAGES 0 20uS 10/300uS CURRENT PULSE (ENERGY CAN BE VERY HIGH) 8/20uS CURRENT PULSE STAGE 1 75KA MOV CLIPS HIGH ENERGY STAGE 2 20KA MOV CLIPS LOWER STAGE 3 CHOKE SLOWS RISETIME STAGE 4 FAST TVS CLIPS BELOW THE T80HV LIMIT. T80HV MAX INPUT (NOT TO SCALE) common mode inductors in this option are custom built for this product. The PV Inputs may be the most vulnerable to surges from nearby lightning strikes because the PV array is a large target and the wires to the electronics cabinet may be relatively long and exposed. Using standard SPDs on these wires is impossible since they carry up to 50 Amps of current from the PV array under normal operation. The inductors must be able to pass 50 Amps continually without saturating or overheating. The The combination of components work together to clip down the potentially damaging voltage and current pulses as shown in the graph on the left. The grounding of the system is critical. The ground point in each combiner box must be terminated on the Apollo panel in order to have equal potential grounds. 4 COMBINER BOX SPD The Citel part number DS72R-120, the 70kA Surge Protector located in the Combiner Box (shown at the right) is an integral part of this system. It is the first line of defense. It must be grounded properly with short direct wires of minimum resistance and inductance. The ground terminal on the SPDs in the Combiner Boxes must be wired directly to the ground bus bar on the lower right of the Apollo PVT panel. This first SPD is considered so important, that we monitor the life of the MOVs inside and report their condition via our Remote Monitoring System.

6 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page WIRING OF PV INPUTS The special 50 Amp Surge Protection Devices for PV inputs are shown in the photo below. The input wires from the PV Combiner Boxes are connected at the right by the labels. The ground wires from the same combiner boxes should be terminated in the bus bar at the bottom. 5kA TVS with 50Amp Common Ground 20kA PV Inputs from Gnd Bus for Ground Strap Mode Inductors Strap MOVs Combiner Boxes Combiners The photo above shows 3 individual 50 Amp SPDs for a PVT panel with 3 T80HVs. The Enhanced Surge Protection Option includes one 50 Amp on the input of each T80HV. TORQUE WARNING It is critically important to tighten all high current connections to the specified torque with a calibrated, insulated Torque Wrench. TORQUE FOR PV INPUT CONNECTORS = 2.3N-m (20 in-lbs) TORQUE FOR GROUND BUS BAR = 4.5 N-m (40 in-lbs)

7 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page BLOCK DIAGRAM FOR THE LOW CURRENT WIRING APOLLO SOLAR ENHANCED SURGE PROTECTION BLOCK DIAGRAM ALL WIRES FROM THE PV ARRAY HAVE SURGE PROTECTION ANTI-THEFT WIRE THRU PV MODULES THESE WIRES CAN BE 15M LONG F C CITEL DLAH-24 DIGITAL I/O APOLLO SOLAR PVT CABINET A to D CONVERTER AND SYSTEM CONROLLER CITEL DLAH-24 X S IRRADIANCE SENSOR AT PV ARRAY THESE WIRES CAN BE 15M LONG COMBINER BOX MOV END OF LIFE ALARM THESE WIRES CAN BE 15M LONG PV INPUT CABLES FROM COMBINER BOX WITH MOVs WIRES IN CABLE TRAYS GROUND WIRE FROM SPDs IN COMBINER BOXES SPD E E C CITEL DLAH-24 SPD D SEPARATE 50A SPD FOR EACH T80HV APOLLO 50 AMP SPD 50A 10uH MOV SPD B 10uH S Terminal Name TVS DIGITAL I/O TVS ALUMINUM CHASSIS GND 1 TO 4 APOLLO T80HV CHARGE CONTROLLERS APOLLO T80HV MPPT CHARGE CONTROLLER 100A +48V BUS -48V BUS POSITIVE GND POINT CONTACTOR 50A CONTACTOR CITEL DS230S- 48DC 30KA SPD C 50mv SHUNT 50A SPD F G H AD AE TO ESSENTIAL LOADS TO NON- ESSENTIAL LOADS POSITIVE OUTPUTS ARE GROUNDED TO 48V BATTERY SINGLE POINT EARTH GROUND 7 WIRING OF LOW CURRENT INPUTS As shown in the Block Diagram above, all system wiring from the location of the PV array is protected with a Surge Protection Device (shown in Yellow) as soon as it enters the Apollo Solar panel. The external wires are meant to be connected directly into the input terminals on the Citel SPDs. The Terminal labels shown on the Block Diagram should be followed.

8 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page The connection labels for the low current wiring is shown in the photo at the left. The Citel SPDs are not upside down. The terminals dictate this orientation. The Ground wires for the SPDs are all in place and must not be removed. TORQUE VALUE FOR ALL CITEL DLAH SPD SCREWS = 0.5 N-m (4.4 in-lbs) 8 48 VOLT OUTPUTS FOR LOADS The Enhanced Surge Protection Option requires no change to the wiring for the Essential and Non-Essential Loads. They are wired to the connectors just like the standard panels since they always included an SPD on the Negative output. The positive output is connected directly to Ground so it does not need any SPD elements. GROUND BUS TORQUE = 4.5 N-m (40 in-lbs)

9 Apollo Solar -- Gen 4 PVT Enhanced Surge Protection Option Page SURGE PROTECTION DISCLAIMER STATEMENT: The Enhanced Surge Protection optional add-on described in this document is intended to provide as much protection as cost effective against damage from near-by lightning strikes. Please note that since a direct lightning strike can discharge an unknown amount of current with a potential difference of unknown voltage, it is impossible to create any device which can provide perfect protection against damage due to lightning. A lightning strike is considered an act of God and as such any damage to the Apollo Solar PVT panels and anything connected it is not covered under the Apollo Solar or any other warrantee. That being said, this Surge Protection Option uses the best design and system components available to avoid damage from lightning strikes which are close to the equipment.